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1. 3-MeO-PCP intoxication in two young men: First in vivo detection in Italy

Author:
Maria Grazia Di Milia,   et al.   ; Elisabetta Bertol; Jennifer Pascali; Diego Palumbo; Valeria Catalani; Alessia Fioravanti; Francesco Mari; Fabio Vaiano;     Show all 8 Authors
Source:
Forensic science international 2017 v.274 pp. 7-12
ISSN:
0379-0738
Subject:
acetonitrile; acidosis; alcohol drinking; anesthetics; blood; forensic sciences; gas chromatography-mass spectrometry; hospitals; hypothermia; liquid chromatography; men; methanol; monitoring; pharmacology; poisoning; psychotropic agents; screening; sedatives; tandem mass spectrometry; toxicity; toxicology; urine; Italy
Abstract:
... 3-MeO-PCP or 3-methoxyphencyclidine is a derivative of phencyclidine. It acts as a dissociative anesthetic and it has allegedly hallucinogenic and sedative effects. There are almost no documented intoxication cases and references about its pharmacology and toxicity in literature. This study presents two concomitant intoxication cases due to consumption of 3-MeO-PCP and alcohol. A 19 (A) and a 21 y ...
DOI:
10.1016/j.forsciint.2016.12.028

2. AC electric field for rapid assembly of nanostructured polyaniline onto microsized gap for sensor devices

Author:
Antonella Maria,   et al.   ; Vera La Ferrara; Gabriella Rametta;     Show all 3 Authors
Source:
Electrophoresis 2015 v.36 no.13 pp. 1459-1465
ISSN:
0173-0835
Subject:
acetonitrile; air; ammonia; dielectrophoresis; electric current; electric field; electrodes; electrophoresis; nanomaterials; prototypes; temperature
Abstract:
... Interconnected network of nanostructured polyaniline (PANI) is giving strong potential for enhancing device performances than bulk PANI counterparts. For nanostructured device processing, the main challenge is to get prototypes on large area by requiring precision, low cost and high rate assembly. Among processes meeting these requests, the alternate current electric fields are often used for nano ...
DOI:
10.1002/elps.201400550

3. Accelerated solvent extraction by using an ‘in-line’ clean-up approach for multiresidue analysis of pesticides in organic honey

Author:
Luca Maria Chiesa,   et al.   ; Giuseppe Federico Labella; Sara Panseri; Domenico Britti; Fabrizio Galbiati; Roberto Villa; Francesco Arioli;     Show all 7 Authors
Source:
Food additives & contaminants 2017 v.34 no.5 pp. 809-818
ISSN:
1944-0057
Subject:
European Union; acetonitrile; guidelines; honey; honey bee colonies; mass spectrometry; multiresidue analysis; pesticide residues; pesticides; solvents
Abstract:
... The worldwide loss of honeybee colonies may be due to their exposure to several contaminants (i.e., pesticides); such contamination may also have impacts on consumers’ health. Therefore, it is essential to develop quick and new methods to detect several pesticide residues in honey samples. In this study, the effectiveness of accelerated solvent extraction (ASE) was compared with QuEChERS methods f ...
DOI:
10.1080/19440049.2017.1292558

4. Acetylcholinesterase-based biosensors for quantification of carbofuran, carbaryl, methylparaoxon, and dichlorvos in 5% acetonitrile

Author:
Ramírez-Silva, Maria Teresa,   et al.   ; Valdés-Ramírez, Gabriela; Cortina, Montserrat; Marty, Jean-Louis;     Show all 4 Authors
Source:
Analytical and bioanalytical chemistry 2008 v.392 no.4 pp. 699-707
ISSN:
1618-2642
Subject:
Drosophila melanogaster; Electrophorus electricus; acetonitrile; acetylcholinesterase; apples; biosensors; carbaryl; carbofuran; cobalt; detection limit; dichlorvos; electrodes; genetic engineering; immobilized enzymes; phosphates; polymers; storage quality
Abstract:
... Amperometric acetylcholinesterase biosensors have been developed for quantification of the pesticides carbofuran, carbaryl, methylparaoxon, and dichlorvos in phosphate buffer containing 5% acetonitrile. Three different biosensors were built using three different acetylcholinesterase (AChE) enzymes--AChE from electric eel, and genetically engineered (B394) and wild-type (B1) AChE from Drosophila me ...
DOI:
10.1007/s00216-008-2290-7
PubMed:
18663432

5. Aflatoxin monitoring in Italian hazelnut products by LC-MS

Author:
Maria Lodovica Gullino,   et al.   ; Ambra Prelle; Davide Spadaro; Angelo Garibaldi;     Show all 4 Authors
Source:
Food additives & contaminants 2012 v.5 no.4 pp. 279-285
ISSN:
1939-3229
Subject:
acetonitrile; aflatoxins; chromatography; hazelnuts; ionization; laws and regulations; methanol; monitoring; tandem mass spectrometry; Italy
Abstract:
... Hazelnut samples of different origin were collected in stores in Northern Italy and analysed for aflatoxin (AF) contamination by a sensitive chromatographic method on the basis of a tandem mass spectrometer with electrospray ionisation. The effects of two extracting solvent mixtures (methanol/water and acetonitrile/water) and different extraction times were tested and compared in terms of recovery ...
DOI:
10.1080/19393210.2012.711371
PubMed:
24786410

6. Analysis of butterfly reproductive proteins using capillary electrophoresis and mass spectrometry

Author:
Maria Khihon Rokhas,   et al.   ; Johanna Liljestrand Rönn; Christer Wiklund; Åsa Emmer;     Show all 4 Authors
Source:
Analytical biochemistry 2019 v.566 pp. 23-26
ISSN:
0003-2697
Subject:
Pieris napi; acetonitrile; adsorption; butterflies; capillary electrophoresis; desorption; electrolytes; females; males; mass spectrometry; methanol; proteins; solubilization; solvents; spermatophores
Abstract:
... A method for analysis of proteins from spermatophores transferred from male to female Pieris napi butterflies during mating has been developed. The proteins were solubilized from the dissected spermatophores using different solubilization agents (water, methanol, acetonitrile and hexafluoroisopropanol). Capillary electrophoresis (CE) analysis was performed using an acidic background electrolyte co ...
DOI:
10.1016/j.ab.2018.11.002

7. Analysis of cocaine and two metabolites in dried blood spots by liquid chromatography with fluorescence detection: A novel test for cocaine and alcohol intake

Author:
Raggi, Maria Augusta,   et al.   ; Mercolini, Laura; Mandrioli, Roberto; Gerra, Gilberto;     Show all 4 Authors
Source:
Journal of chromatography 2010 v.1217 no.46 pp. 7242-7248
ISSN:
0021-9673
Subject:
acetonitrile; alcohol drinking; blood; cocaine; ethanol; fluorescence; high performance liquid chromatography; metabolites; monitoring; pH; pretreatment; psychotropic agents; solid phase extraction; solvents
Abstract:
... An original HPLC method coupled to spectrofluorimetric detection is presented for the simultaneous analysis in dried blood spots (DBS) of cocaine and two important metabolites, namely benzoylecgonine (its main metabolite) and cocaethylene (the active metabolite formed in the presence of ethanol). The chromatographic analysis was carried out on a C8 column, using a mobile phase containing phosphate ...
DOI:
10.1016/j.chroma.2010.09.037

8. Analysis of risperidone and 9-hydroxyrisperidone in human plasma, urine and saliva by MEPS-LC-UV

Author:
Maria Augusta Raggi,   et al.   ; Roberto Mandrioli; Laura Mercolini; Domenico Lateana; Giancarlo Boncompagni;     Show all 5 Authors
Source:
Journal of chromatography 2011 v.879 no.2 pp. 167-173
ISSN:
1570-0232
Subject:
acetonitrile; blood plasma; high performance liquid chromatography; humans; metabolites; microextraction; monitoring; pH; patients; pretreatment; saliva; therapeutics; tranquilizers; triethylamine; urine
Abstract:
... Risperidone is currently one of the most frequently prescribed atypical antipsychotic drugs; its main active metabolite 9-hydroxyrisperidone contributes significantly to the therapeutic effects observed. An original analytical method is presented for the simultaneous analysis of risperidone and the metabolite in plasma, urine and saliva by high-performance liquid chromatography coupled to an origi ...
DOI:
10.1016/j.jchromb.2010.11.033
PubMed:
21183412

9. Analysis of tricyclic antidepressants in human plasma using online-restricted access molecularly imprinted solid phase extraction followed by direct mass spectrometry identification/quantification

Author:
Isabela Maria Campos Tavares,   et al.   ; Mariane Gonçalves Santos; Adriano Francisco Barbosa; Jefferson Bettini; Eduardo Costa Figueiredo;     Show all 5 Authors
Source:
Talanta 2016 pp. -
ISSN:
0039-9140
Subject:
acetic acid; acetonitrile; antidepressants; aqueous solutions; bovine serum albumin; chromatography; correlation; humans; hydrophilicity; mass spectrometry; molecular imprinting; polymers; solid phase extraction; spectrometers
Abstract:
... The use of a new class of hybrid materials, called restricted access molecularly imprinted polymers (RAMIPs) seems to present a good strategy for the sample preparation of complex matrices, since these materials combine good protein elimination capacity with high degree selectivity. Mass spectrometers (MS) have been successfully used for polar drug identification and quantification. In order to co ...
DOI:
10.1016/j.talanta.2016.10.047

10. Analytical Quality by Design (AQbD) as a multiaddressable platform for co-encapsulating drug assays

Author:
Maria Mendes,   et al.   ; João Basso; Tânia F. G. G. Cova; João J. Sousa; Alberto A. C. C. Pais; Carla Vitorino;     Show all 6 Authors
Source:
Analytical methods 2018 v.10 no.47 pp. 5659-5671
ISSN:
1759-9679
Subject:
Food and Drug Administration; acetic acid; acetonitrile; atorvastatin; curcumin; drugs; lipids; nanoparticles; particle size; quality control; reversed-phase high performance liquid chromatography; risk assessment; risk factors; statistical models
Abstract:
... The current study describes the application of an Analytical Quality by Design (AQbD) approach for the selection and optimization of a reversed-phase high performance liquid chromatography (RP-HPLC) method to simultaneously quantify curcumin, atorvastatin calcium and celecoxib in lipid nanoparticles. Risk assessment was carried out to set the risk factors that may have a significant influence on m ...
DOI:
10.1039/c8ay01695j

11. Another glimpse over the salting-out assisted liquid–liquid extraction in acetonitrile/water mixtures

Author:
Inês Maria Valente,   et al.   ; Luís Moreira Gonçalves; José António Rodrigues;     Show all 3 Authors
Source:
Journal of chromatography 2013 v.1308 no. pp. 58-62
ISSN:
0021-9673
Subject:
acetates; acetonitrile; beers; carbonates; headspace analysis; high performance liquid chromatography; liquid-liquid extraction; magnesium sulfate; proteins; separation; sodium chloride; solvents
Abstract:
... The use of the salting-out effect in analytical chemistry is very diverse and can be applied to increase the volatility of the analytes in headspace extractions, to cause the precipitation of proteins in biological samples or to improve the recoveries in liquid–liquid extractions. In the latter, the salting-out process can be used to create a phase separation between water-miscible organic solvent ...
DOI:
10.1016/j.chroma.2013.08.014

12. Assessment of bacterial resistance to organic solvents using a combined confocal laser scanning and atomic force microscopy (CLSM/AFM)

Author:
Maria S. Kuyukina,   et al.   ; Irena B. Ivshina; Irina O. Korshunova; Ekaterina V. Rubtsova;     Show all 4 Authors
Source:
Journal of microbiological methods 2014 v.107 pp. 23-29
ISSN:
0167-7012
Subject:
acetonitrile; atomic force microscopy; bacteria; butanol; cell membranes; confocal laser scanning microscopy; resistance mechanisms; roughness; solvents; toluene; viability
Abstract:
... Using combined confocal laser scanning and atomic force microscopy (CLSM/AFM), bacterial viability under organic solvent stress was assessed at single cell level. Solvent-exposed bacteria stained with the LIVE/DEAD BacLight fluoresced green or red, allowing viable and dead cell discrimination. However, with toluene, butanol and acetonitrile, dually fluorescent cells appeared having compromised cel ...
DOI:
10.1016/j.mimet.2014.08.020

13. Asymmetric chemoenzymatic synthesis of N-acetyl-α-amino esters based on lipase-catalyzed kinetic resolutions through interesterification reactions

Author:
Maria da Conceição Ferreira de Oliveira; Nágila Maria Pontes Silva Ricardo,   et al.   ; Marcos Reinaldo da Silva; Marcos Carlos de Mattos; Telma Leda Gomes de Lemos; Gonzalo de Gonzalo; Iván Lavandera; Vicente Gotor-Fernández; Vicente Gotor;     Show all 9 Authors
Source:
Tetrahedron 2014 v.70 pp. 2264-2271
ISSN:
0040-4020
Subject:
Rhizomucor miehei; acetonitrile; acid hydrolysis; butyrates; carboxylic ester hydrolases; catalysts; chemical structure; esterification; halides; phenylalanine; stereochemistry
Abstract:
... Several phenylalanine analogs have been synthesized through a four-step route starting from easily available ethyl acetamidocyanoacetate. In a first reaction, and making use of phase transfer catalysts, this compound reacted with several alkyl halides, being benzyltributylammonium chloride identified as the best one for the production of a series of quaternary amino acids in moderate to excellent ...
DOI:
10.1016/j.tet.2014.02.012

14. Behavior of detoxifying enzymes of Aedes aegypti exposed to girgensohnine alkaloid analog and Cymbopogon flexuosus essential oil

Author:
Angela Maria Palacio-Cortés,   et al.   ; Aurora L. Carreño Otero; Mario Antonio Navarro-Silva; Vladimir V. Kouznetsov; Jonny E. Duque L.;     Show all 5 Authors
Source:
Comparative Biochemistry and Physiology, Part C 2017 pp. -
ISSN:
1532-0456
Subject:
Aedes aegypti; Cymbopogon flexuosus; acetonitrile; acetylcholinesterase; adults; alkaloids; enzyme activity; essential oils; glutathione transferase; insecticides; larvae; mosquito control; Colombia
Abstract:
... Because mosquito control depend on the use of commercial insecticides and resistance has been described in some of them, there is a need to explore new molecules no resistant. In vivo effects of girgensohnine analog 2-(3,4-dimethoxyphenyl)-2-(piperidin-1-yl)acetonitrile DPPA and Cymbopogon flexuosus essential oil CFEO, on the detoxifying enzymes acetylcholinesterase (AChE), glutathione-S-transfera ...
DOI:
10.1016/j.cbpc.2017.11.002

15. Bioactive Metabolites Produced by Penicillium sp.1 and sp.2, Two Endophytes Associated with Alibertia macrophylla (Rubiaceae)

Author:
Maria C. M. Young,   et al.   ; Camila M. Oliveira; Geraldo H. Silva; Luis O. Regasini; Lisinéia M. Zanardi; Alana H. Evangelista; Vanderlan S. Bolzani; Angela R. Araujo;     Show all 8 Authors
Source:
Zeitschrift für Naturforschung 2014 v.64 no.11-12 pp. 824-830
ISSN:
1865-7125
Subject:
Cladosporium cladosporioides; Penicillium; Rubiaceae; acetonitrile; acetylcholinesterase; active ingredients; chromatography; corn; endophytes; fractionation; fungi; leaves; metabolites; uracil
Abstract:
... In the course of our continuous search for bioactive metabolites from endophytic fungi living in plants from the Brazilian fl ora, leaves of Alibertia macrophylla (Rubiaceae) were submitted to isolation of endophytes, and two species of Penicillium were isolated. The acetonitrile fraction obtained in corn from a culture of Penicillium sp.1 afforded orcinol (1). On the other hand, Penicillium sp.1 ...
DOI:
10.1515/znc-2009-11-1212

16. Bioinspired Tungsten Dithiolene Catalysts for Hydrogen Evolution: A Combined Electrochemical, Photochemical, and Computational Study

Author:
Gomez-Mingot Maria,   et al.   ; Porcher Jean-Philippe; Todorova Tanya K.; Fogeron Thibault; Mellot-Draznieks Caroline; Li Yun; Fontecave Marc;     Show all 7 Authors
Source:
Journal of physical chemistry 2015 v.119 no.43 pp. 13524-13533
ISSN:
1520-5207
Subject:
acetonitrile; active sites; ascorbic acid; catalysts; electrochemistry; electrolysis; formates; hydrogen; hydrogen production; irradiation; photochemistry; photosensitizing agents; protons; tungsten
Abstract:
... Bis(dithiolene)tungsten complexes, WⱽᴵO₂ (L = dithiolene)₂ and WᴵⱽO (L = dithiolene)₂, which mimic the active site of formate dehydrogenases, have been characterized by cyclic voltammetry and controlled potential electrolysis in acetonitrile. They are shown to be able to catalyze the electroreduction of protons into hydrogen in acidic organic media, with good Faradaic yields (75–95%) and good acti ...
DOI:
10.1021/acs.jpcb.5b01615

17. Blood matrix effects for male and female Wistar rats, in simultaneous HPLC-UV determination of riparin I and III from Aniba riparia (Nees) Mez. (Lauraceae)

Author:
Adriana Maria Fernandes de Oliveira; José Maria Barbosa-Filho,   et al.   ; Sócrates Golzio dos Santos; Karine Formiga Queiroga; Josean Fechine Tavares; Stanley Juan Chavez Gutierrez; Margareth de Fátima Formiga Melo Diniz; Marcelo Sobral da Silva;     Show all 8 Authors
Source:
Talanta 2011 v.86 no. pp. 233-240
ISSN:
0039-9140
Subject:
Aniba; acetonitrile; alkaloids; amides; blood; centrifugation; females; high performance liquid chromatography; liquid-liquid extraction; males; mice; muscles; oral administration; rats; sedatives; solvents
Abstract:
... Aniba riparia (Nees) Mez. (Lauraceae) is popularly known as “louro”, and is found in Amazonia and in the Guianas, its distribution extends to the Andes. Alkamide alkaloids were isolated from its green fruit; they were denominated riparin I (methyl ether of N-benzoyl tyramine), riparin II (methyl ether of N-2-hydroxy-benzoyl tyramine) and riparin III (methyl ether of N-2,6-dihydroxy-benzoyl tyramin ...
DOI:
10.1016/j.talanta.2011.09.008

18. Correlations between the zeta potentials of silica hydride-based stationary phases, analyte retention behaviour and their ionic interaction descriptors

Author:
Maria T. Matyska,   et al.   ; Chadin Kulsing; Yuanzhong Yang; Caesar Munera; Colby Tse; Joseph J. Pesek; Reinhard I. Boysen; Milton T.W. Hearn;     Show all 8 Authors
Source:
Analytica chimica acta 2014 v.817 pp. 48-60
ISSN:
0003-2670
Subject:
acetonitrile; analytical chemistry; chromatography; energy; formic acid; hydrides; silica; zeta potential
Abstract:
... In this study, the zeta potentials of type-B silica, bare silica hydride, the so-called Diamond Hydride™ and phenyl substituted silica hydride stationary phases have been measured in aqueous-organic media and correction procedures developed to account for the more negative zeta potential values in media containing different acetonitrile contents. Retention studies of 16 basic, acidic and neutral c ...
DOI:
10.1016/j.aca.2014.01.054

19. Determination of Cephalosporins by UHPLC-DAD Using Molecularly Imprinted Polymers

Author:
Maria D P T Sotomayor,   et al.   ; Alen N Baeza-Fonte; Idenia Garcés-Lobo; Markel D Luaces-Alberto; Luís Moreira Gonçalves; Arístides C Valdés-González;     Show all 6 Authors
Source:
Journal of chromatographic science 2018 v.56 no.2 pp. 187-193
ISSN:
1945-239X
Subject:
acetonitrile; ceftazidime; ceftriaxone; cephalexin; detection limit; dimethyl sulfoxide; high performance liquid chromatography; molecular imprinting; polymers; ultra-performance liquid chromatography
Abstract:
... Molecularly imprinted polymers (MIPs) were synthesized for the determination of cephalosporins (cephazolin, ceftazidime, cefotaxime, ceftriaxone, cefepime and cephalexin) by ultra-high performance liquid chromatography with diode-array detection (UHPLC-DAD). After optimization, MIPs were synthesized using cephazolin as the template, methacrylic acid as the functional monomer, triethylenglycol dime ...
DOI:
10.1093/chromsci/bmx099

20. Determination of Mycotoxins in Cereal-Based Porridge Destined for Infant Consumption by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry

Author:
Maria Heloísa Paulino de Moraes,   et al.   ; André Victor Sartori; Rosana Pereira dos Santos; Yuri Pereira Souza; Armi Wanderley da Nóbrega;     Show all 5 Authors
Source:
Food analytical methods 2017 v.10 no.12 pp. 4049-4061
ISSN:
1936-9751
Subject:
acetonitrile; aflatoxins; deoxynivalenol; formic acid; fumonisins; laws and regulations; liquid chromatography; ochratoxin A; solvents; sonication; statistical analysis; sterigmatocystin; tandem mass spectrometry; zearalenone; Brazil
Abstract:
... An analytical method applying ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for the determination of aflatoxins M2, M1, G2, G1, B2, B1, deoxynivalenol, ochratoxin A, fumonisins B1 and B2, hydrolyzed fumonisins B1 and B2, zearalenone and sterigmatocystin in cereal-based porridge destined for infant consumption was developed and validated. The mycotoxins were ex ...
DOI:
10.1007/s12161-017-0965-4

21. Determination of S-adenosylmethionine and S-adenosylhomocysteine in blood plasma by UPLC with fluorescence detection

Author:
Maria Petrovna Kruglova,   et al.   ; Alexander Vladimirovich Ivanov; Ekaterina Alexandrovna Dubchenko; Edward Danielevich Virus; Polina Olegovna Bulgakova; Valery Vasil'evich Alexandrin; Anatolij Nikolaevich Fedoseev; Alexey Nikolaevich Boyko; Sergej Vitalievich Grachev; Aslan Amirkhanovich Kubatiev;     Show all 10 Authors
Source:
Journal of chromatography 2019 v.1124 pp. 366-374
ISSN:
1570-0232
Subject:
S-adenosylmethionine; acetic acid; acetonitrile; blood plasma; chemical species; derivatization; detection limit; fluorescence; metabolites; phenylboronic acids; potassium dihydrogen phosphate; solid phase extraction; ultra-performance liquid chromatography; volunteers
Abstract:
... A validated approach to determine various methionine cycle metabolites (S-adenosylmethionine, S-adenosylhomocysteine, and methylthioadenosine) in human blood plasma is offered. The approach is based on solid-phase extraction (with grafted phenylboronic acid) and derivatization with chloroacetaldehyde followed by ultra-performance liquid chromatography with fluorescence detection. We used a 100 × 2 ...
DOI:
10.1016/j.jchromb.2019.06.032

22. Determination of Vecuronium Bromide in Pharmaceuticals: Development, Validation and Comparative Study of HPLC and CZE Analytical Methods

Author:
Santoro, Maria Inês Rocha Miritello; Kedor-Hackmann, Érika Rosa Maria,   et al.   ; García, Pedro López; Gomes, Fabio Pereira; Quero, Jose Luis Vilchez; Montón, Alberto Navalón; Montoya, Guillermo Crovetto; Cabrera, Mercedes Aguilera;     Show all 8 Authors
Source:
Chromatographia 2011 v.73 no.7-8 pp. 799-805
ISSN:
0009-5893
Subject:
acetonitrile; anesthesia; drugs; electrolytes; high performance liquid chromatography; pH; quantitative analysis; quinine; skeletal muscle; sodium phosphate; sulfates
Abstract:
... Vecuronium bromide is a neuromuscular blocking agent used for anesthesia to induce skeletal muscle relaxation. HPLC and CZE analytical methods were developed and validated for the quantitative determination of vecuronium bromide. The HPLC method was achieved on an amino column (Luna 150 × 4.6 mm, 5 μm) using UV detection at 205 nm. The mobile phase was composed of acetonitrile:water containing 25. ...
DOI:
10.1007/s10337-011-1945-2

23. Determination of cocaine in postmortem human liver exposed to overdose. Application of an innovative and efficient extraction/clean up procedure and gas chromatography–mass spectrometry analysis

Author:
Maria Eliana Lopes Ribeiro de Queiroz,   et al.   ; Elisângela Jaqueline Magalhães; Marcus Luiz de Oliveira Penido; Marco Antônio Ribeiro Paiva; Janaína Aparecida Reis Teodoro; Rodinei Augusti; Clésia Cristina Nascentes;     Show all 7 Authors
Source:
Journal of chromatography 2013 v.1309 no. pp. 15-21
ISSN:
0021-9673
Subject:
acetonitrile; cattle; cocaine; gas chromatography-mass spectrometry; humans; ionic strength; liver; overdose; pH; sodium chloride; solvents; temperature
Abstract:
... A simple and efficient method was developed for the determination of cocaine in post-mortem samples of human liver via solid–liquid extraction with low temperature partitioning (SLE–LTP) and analysis by gas chromatography coupled to mass spectrometry (GC–MS). The extraction procedure was optimized by evaluating the influence of the following variables: pH of the extract, volume and composition of ...
DOI:
10.1016/j.chroma.2013.08.039

24. Determination of ethyl carbamate in spirits using salting-out assisted liquid–liquid extraction and high performance liquid chromatography with fluorimetric detection

Author:
Inês Maria Valente,   et al.   ; Rui Miguel Ramos; Luís Moreira Gonçalves; José António Rodrigues;     Show all 4 Authors
Source:
Analytical methods 2014 v.6 no.22 pp. 9136-9141
ISSN:
1759-9679
Subject:
acetonitrile; derivatization; detection limit; ethyl carbamate; fluorometry; high performance liquid chromatography; hydrochloric acid; liquid-liquid extraction; reversed-phase liquid chromatography; separation; sodium chloride; solvents; toxicity
Abstract:
... In this work, a simple methodology was developed for the determination of ethyl carbamate (EC) in spirits by high performance liquid chromatography with fluorimetric detection. The sample is subjected to salting-out assisted liquid–liquid extraction (SALLE) using a 9-xanthydrol/acetonitrile solution for the simultaneous extraction and derivatisation of EC. Extraction/derivatization occurs under ac ...
DOI:
10.1039/c4ay02075h

25. Determination of fluoxetine and norfluoxetine enantiomers in human plasma by polypyrrole-coated capillary in-tube solid-phase microextraction coupled with liquid chromatography-fluorescence detection

Author:
Queiroz, Maria Eugênia Costa,   et al.   ; Silva, Bruno José Gonçalves; Lanças, Fernando Mauro;     Show all 3 Authors
Source:
Journal of chromatography 2009 v.1216 no.49 pp. 8590-8597
ISSN:
0021-9673
Subject:
absorbance; acetonitrile; antidepressants; blood proteins; chromatography; correlation; elderly; enantiomers; fluorescence; humans; pH; patients; potassium; sodium phosphate; solid phase microextraction; therapeutics
Abstract:
... A sensitive, selective, and reproducible in-tube polypyrrole-coated capillary (PPY) solid-phase microextraction and liquid chromatographic method for fluoxetine and norfluoxetine enantiomers analysis in plasma samples has been developed, validated, and further applied to the analysis of plasma samples from elderly patients undergoing therapy with antidepressants. Important factors in the optimizat ...
DOI:
10.1016/j.chroma.2009.10.034

26. Determination of hormonally active chlorinated chemicals in waters at sub µg/L level using stir bar sorptive extraction-liquid desorption followed by negative chemical ionization-gas chromatography triple quadrupole mass spectrometry

Author:
Maria Jose Gómez,   et al.   ; Sridhara Chary Nallanthigal; Sonia Herrera; Amadeo. R. Fernández-Alba;     Show all 4 Authors
Source:
International journal of environmental analytical chemistry 2014 v.94 no.1 pp. 48-64
ISSN:
1029-0397
Subject:
acetonitrile; desorption; detection limit; effluents; endosulfan; environmental quality; gas chromatography; ionization; mass spectrometry; mechanization; mixing; river water; screening; sodium chloride; surface water; wastewater; water policy; Spain
Abstract:
... A new analytical method has been developed for the screening, evaluation and determination of sub µg/L concentrations of chlorinated chemicals in environmental waters. Ten different compounds included in the European water policy have been considered and determined by stir bar sorptive extraction (SBSE) followed by liquid desorption and negative chemical ionization gas chromatography coupled to tr ...
DOI:
10.1080/03067319.2013.775278

27. Determination of parabens in shampoo using high performance liquid chromatography with amperometric detection on a boron-doped diamond electrode

Author:
Letícia Maria da Silva Cruz,   et al.   ; Isarita Martins; Franciely Cristiani Carreira; Larissa S. Canaes; Francisco Alberto de Souza Campos Junior; Susanne Rath;     Show all 6 Authors
Source:
Talanta 2011 v.85 no.1 pp. 1-7
ISSN:
0039-9140
Subject:
acetonitrile; cosmetics; dermatitis; drugs; electrochemistry; electrodes; estrogenic properties; foods; high performance liquid chromatography; hypersensitivity; methylparaben; pH; platinum; preservatives; quality control; solid phase extraction; stainless steel
Abstract:
... Methylparaben (MePa), ethylparaben (EtPa) and propylparaben (PrPa) have been widely used, among others, as chemical preservatives in cosmetics, drugs and foods. As these compounds are linked with allergies, dermatitis and estrogenic properties, it is necessary to control the concentration of these substances in different matrices. The aim of this paper are: to evaluate the electrochemical behavior ...
DOI:
10.1016/j.talanta.2011.04.047

28. Determination of sulfonamide antibiotics and metabolites in liver, muscle and kidney samples by pressurized liquid extraction or ultrasound-assisted extraction followed by liquid chromatography–quadrupole linear ion trap-tandem mass spectrometry (HPLC–QqLIT-MS/MS)

Author:
Maria do Carmo Ruaro Peralba,   et al.   ; Rodrigo Barcellos Hoff; Tânia Mara Pizzolato; M. Silvia Díaz-Cruz; Damià Barceló;     Show all 5 Authors
Source:
Talanta 2015 v.134 pp. 768-778
ISSN:
0039-9140
Subject:
acetonitrile; antibiotics; detection limit; hexane; kidneys; liquid chromatography; liquid-liquid extraction; liquids; liver; mass spectrometry; metabolites; muscles; sulfonamides; ultrasonic treatment; veterinary medicine
Abstract:
... Sulfonamides are widely used in human and veterinary medicine. The presence of sulfonamides residues in food is an issue of great concern. Throughout the present work, a method for the targeted analysis of 16 sulfonamides and metabolites residue in liver of several species has been developed and validated. Extraction and clean-up has been statistically optimized using central composite design expe ...
DOI:
10.1016/j.talanta.2014.10.045

29. Determination of vitamins A and E in cooked sausages

Author:
Sancho Ortiz, Maria Teresa,   et al.   ; Valls, Felicidad; Fernández-Muiño, Miguel A.; Checa, Martín A.;     Show all 4 Authors
Source:
European food research & technology 2007 v.226 no.1-2 pp. 181-185
ISSN:
1438-2377
Subject:
acetonitrile; detection limit; fluorescence; food research; hexane; oxidation; pyrogallol; reversed-phase high performance liquid chromatography; saponification; sausages; tetrahydrofuran; vitamin A
Abstract:
... A reliable and sensitive reverse-phase HPLC method is described for the separation and quantification of all-trans-retinol and dl-α-tocopherol in cooked sausages. Samples were chromatographed with UV and fluorescence detection on a 15 cm x 0.4 cm i.d. Spherisorb ODS-2, 5 μm column, using as mobile phase a mixture of 90% acetonitrile and 10% tetrahydrofuran. Sample preparation included saponificati ...
DOI:
10.1007/s00217-006-0524-5

30. Determination of γ‐hydroxybutyric acid in saliva by capillary electrophoresis coupled with contactless conductivity and indirect UV absorbance detectors

Author:
Maria Kulp,   et al.   ; Jekaterina Mazina; Piret Saar‐Reismaa; Mihkel Kaljurand; Merike Vaher;     Show all 5 Authors
Source:
Electrophoresis 2015 v.36 no.24 pp. 3042-3049
ISSN:
0173-0835
Subject:
absorbance; acetonitrile; arginine; capillary electrophoresis; cetyltrimethylammonium bromide; detectors; forensic sciences; maleic acid; saliva; screening
Abstract:
... The aim of the current study was to optimise and validate the methodology for determination of γ‐hydroxybutyric acid (GHB) in saliva by CE combined with a contactless conductivity detector (C⁴D) and indirect UV absorbance detection (λABS = 210 nm). The optimized BGE, consisting of 8.5 mM maleic acid, 17 mM arginine, 255 μM cetyltrimethylammonium bromide (CTAB), and 15% acetonitrile, was evaluated ...
DOI:
10.1002/elps.201500293

31. Development and validation of HPLC–MS/MS procedure for determination of 3,4,4′,5-tetra-methoxystilbene (DMU-212) and its metabolites in ovarian cancer cells and culture medium

Author:
Anna Maria Sulej-Suchomska,   et al.   ; Agnieszka Klupczynska; Hanna Piotrowska-Kempisty; Marcin Wierzchowski; Jadwiga Jodynis-Liebert; Zenon J. Kokot;     Show all 6 Authors
Source:
Journal of chromatography 2017 v.1060 pp. 30-35
ISSN:
1570-0232
Subject:
acetonitrile; ammonium acetate; animal ovaries; antineoplastic activity; culture media; formic acid; high performance liquid chromatography; humans; metabolites; monitoring; neoplasm cells; ovarian neoplasms; resveratrol; solvents; spectrometers
Abstract:
... The synthetic resveratrol analogue DMU-212 (3,4,4′,5-tetramethoxystilbene) has been shown to possess stronger anticancer activity than resveratrol in a variety of tumour cells. To date, there has been no appropriate procedure that would ensure a reliable data about levels of metabolic products of DMU-212 in cancer cell lines. The purpose of this study was to develop a new procedure for determinati ...
DOI:
10.1016/j.jchromb.2017.05.015

32. Development and validation of a HPLC method for the assay of dapivirine in cell-based and tissue permeability experiments

Author:
Maria Fernanda Bahia,   et al.   ; José das Neves; Bruno Sarmento; Mansoor Amiji;     Show all 4 Authors
Source:
Journal of chromatography 2012 v.911 no. pp. 76-83
ISSN:
1570-0232
Subject:
RNA-directed DNA polymerase; acetonitrile; antiretroviral agents; detection limit; diphenylamine; drugs; experimental design; high performance liquid chromatography; in vitro studies; nanoparticles; permeability; storage conditions
Abstract:
... Dapivirine, a non-nucleoside reverse transcriptase inhibitor, is being currently used for the development of potential anti-HIV microbicide formulations and delivery systems. A new high-performance liquid chromatography (HPLC) method with UV detection was developed for the assay of this drug in different biological matrices, namely cell lysates, receptor media from permeability experiments and hom ...
DOI:
10.1016/j.jchromb.2012.10.034

33. Development and validation of a fast RP-HPLC method to determine the analogue of the thyroid hormone, 3,5,3′-triiodothyroacetic acid (TRIAC), in polymeric nanoparticles

Author:
Maria Fátima G. F. da Silva,   et al.   ; Karen C. dos Santos; João B. Fernandes; Paulo C. Vieira; Igor Polikarpov; Valtencir Zucolotto; Moacir R. Forim;     Show all 7 Authors
Source:
Analytical methods 2011 v.3 no.9 pp. 1936-1942
ISSN:
1759-9679
Subject:
acetonitrile; lactones; nanoparticles; pH; polyhydroxybutyrate; polymethylmethacrylate; reversed-phase high performance liquid chromatography; temperature; thyroid hormones; triethylamine; wavelengths
Abstract:
... The objective of this work was to develop and validate a rapid Reversed-Phase High-Performance Liquid Chromatography method for the quantification of 3,5,3′-triiodothyroacetic acid (TRIAC) in nanoparticles delivery system prepared in different polymeric matrices. Special attention was given to developing a reliable reproductive technique for the pretreatment of the samples. Chromatographic runs we ...
DOI:
10.1039/c1ay05169e

34. Development and validation of a high performance liquid chromatography-tandem mass spectrometry method for the absolute analysis of 17 α D-amino acids in cooked meals

Author:
Maria Paz Lorenzo,   et al.   ; Cecilia Barbas-Bernardos; Isabel Garcia-Perez; Vanesa Alonso-Herranz; Jeremy Nicholson; Antonia Garcia;     Show all 6 Authors
Source:
Journal of chromatography 2020 v.1611 pp. 460598
ISSN:
0021-9673
Subject:
Dietary Guidelines; World Health Organization; acetonitrile; amino acids; ammonium bicarbonate; breakfast; cooked foods; diet; dinner; electrospray ionization mass spectrometry; high performance liquid chromatography; isotope labeling; lunch; methanol; monitoring; quality control; tandem mass spectrometry
Abstract:
... In the nutrition field, there is a lack of understanding about the impact that dietary chiral composition may have on health, especially regarding cooked meals. Chiral amino acids (AAs) are naturally present in food and their proportion may vary quite a lot. Besides, the D-amino acids (D-AAs) are present in very low concentration compared to L-AAs, so very sensitive methods are required for their ...
DOI:
10.1016/j.chroma.2019.460598

35. Development and validation of an HPLC-DAD method for the simultaneous determination of most common rice pesticides in paddy water systems

Author:
Maria Papageorgiou,   et al.   ; Emmanouil D. Tsochatzis; Roxani Tzimou-Tsitouridou; Urania Menkissoglu-Spiroudi; Dimitrios G. Karpouzas;     Show all 5 Authors
Source:
International journal of environmental analytical chemistry 2012 v.92 no.5 pp. 548-560
ISSN:
1029-0397
Subject:
acetonitrile; azoxystrobin; basins; deltamethrin; detection limit; ecosystems; high performance liquid chromatography; metabolites; molinate; monitoring; paddies; pesticide residues; profoxydim; propanil; rice; solid phase extraction; surface water; tricyclazole; water pollution; water quality; water resources; watersheds
Abstract:
... Rice crop is mainly cultivated in large river basins which constitute unique ecosystems and their ecological quality is invaluable. However, the high loads of pesticides used in rice cultivation contribute to the contamination of the water resources in such rice-cultivated regions. To regularly monitor the quality of such water resources there is a need for a rapid and sensitive multi-residue anal ...
DOI:
10.1080/03067310903229943

36. Development of a high-performance liquid chromatography method to assess bisphenol F levels in milk

Author:
Maria Carmela Ferrante,   et al.   ; Serena Santonicola; Giampaolo Colavita; Raffaelina Mercogliano;     Show all 4 Authors
Source:
Italian journal of food safety 2021 v.10 no.4 pp. 9975
ISSN:
2239-7132
Subject:
acetonitrile; bisphenol A; bisphenol F; dairies; endocrine-disrupting chemicals; fluorescence; food safety; high performance liquid chromatography; pasteurization; solid phase extraction; solvents; toxicity; whole milk
Abstract:
... Bisphenol F (BPF) is a bisphenol A (BPA) analogue. As an endocrine disruptor, BPF shows a similar BPA hormonal activity and greater endocrine effects. To assess BPF levels in milk a selective method based on solvent extraction with acetonitrile, solid-phase extraction (SPE), high-performance liquid chromatography with fluorescence detection (HPLC-FD) system, was developed. The method showed high r ...
DOI:
10.4081/ijfs.2021.9975

37. Development of a modified acetonitrile-based extraction procedure followed by ultra-high performance liquid chromatography–tandem mass spectrometry for the analysis of psychiatric drugs in sediments

Author:
Maria João Ramalhosa,   et al.   ; Lúcia H.M.L.M. Santos; Marta Ferreira; Cristina Delerue-Matos;     Show all 4 Authors
Source:
Journal of chromatography 2016 v.1437 pp. 37-48
ISSN:
0021-9673
Subject:
acetonitrile; detection limit; drugs; humans; liquid chromatography; metabolites; rivers; sediments; solid phase extraction; solvents; statistical analysis; tandem mass spectrometry
Abstract:
... An analytical method based on a modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction procedure followed by ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was developed for the analysis of psychiatric drugs in sediments. An optimized approach was applied in sample preparation by using basic acetonitrile as extraction solvent. Extraction ...
DOI:
10.1016/j.chroma.2016.01.079

38. Development of high-throughput multi-residue method for non-steroidal anti-inflammatory drugs monitoring in swine muscle by LC-MS/MS

Author:
Ana Maria Bergold,   et al.   ; Tamara S. Castilhos; Fabiano Barreto; Leonardo Meneghini;     Show all 4 Authors
Source:
Food additives & contaminants 2016 v.33 no.7 pp. 1166-1174
ISSN:
1944-0057
Subject:
acetic acid; acetonitrile; ammonium acetate; evaporation; food availability; hexane; mass spectrometry; metabolites; monitoring; multiresidue analysis; muscles; nonsteroidal anti-inflammatory agents; spectrometers; swine
Abstract:
... A reliable and simple method for the detection and quantification of residues of 14 non-steroidal anti-inflammatory drugs and a metamizole metabolite in swine muscle was developed using liquid chromatography-electrospray ionisation-tandem mass spectrometry (LC-ESI-MS/MS). The samples were extracted with acetonitrile (ACN) in solid–liquid extraction followed by a low-temperature partitioning (LLE-L ...
DOI:
10.1080/19440049.2016.1198497

39. Developments in the synthesis of a water compatible molecularly imprinted polymer as artificial receptor for detection of 3-nitro-l-tyrosine in neurological diseases

Author:
Maria Rosaria Lazzoi,   et al.   ; Lucia Mergola; Sonia Scorrano; Roberta Del Sole; Giuseppe Vasapollo;     Show all 5 Authors
Source:
Biosensors & bioelectronics 2013 v.40 pp. 336-341
ISSN:
0956-5663
Subject:
acetic acid; acetonitrile; binding properties; binding sites; biosensors; detection limit; humans; molecular imprinting; neurodegenerative diseases; oxidative stress; polymerization; polymers; solid phase extraction; urine; washing
Abstract:
... A highly selective water compatible molecularly imprinted polymer (MIP) for 3-nitro-l-tyrosine (3NT), an oxidative stress marker associated with neurodegenerative disorders, was prepared and its use as solid-phase extraction (SPE) sorbent material was demonstrated. The MIP was prepared by bulk polymerization using methacrylic acid as functional monomer and acetonitrile as porogen with traces of ac ...
DOI:
10.1016/j.bios.2012.07.074

40. Dispersive liquid-liquid microextraction based on solidification of floating organic drop and high-performance liquid chromatography to the analysis of cocaine’s major adulterants in human urine

Author:
Maria Fernanda Pimentel,   et al.   ; Laís Cristina Santana Sena; Humberto Reis Matos; Haroldo Silveira Dórea; Danielle Cristine Almeida Silva de Santana; Fernando José Malagueño de Santana;     Show all 6 Authors
Source:
Toxicology 2017 v.376 pp. 102-112
ISSN:
0300-483X
Subject:
acetonitrile; adulterated products; ambient temperature; buffers; caffeine; cocaine; high performance liquid chromatography; humans; levamisole; lidocaine; liquid-phase microextraction; pH; patients; poisoning; sodium chloride; sodium phosphate; solidification; solvents; statistical analysis; urine
Abstract:
... A simple method has been proposed for the determination of cocaine’s major adulterants (caffeine, levamisole, lidocaine, phenacetin, diltiazem, and hydroxyzine) in human urine by dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) in combination with high-performance liquid chromatography – photodiode array detector (HPLC-PDA). The reversed-phase c ...
DOI:
10.1016/j.tox.2016.04.008

41. Do Molecular Gelators Cluster in Hansen Space?

Author:
Maria G. Corradini,   et al.   ; Yaqi Lan; Michael A. Rogers;     Show all 3 Authors
Source:
Crystal Growth & Design 2014 v.14 no.9 pp. 4811-4818
ISSN:
1528-7505
Subject:
acetonitrile; benzene; design; ethanol; gelation; gels; hydrogen bonding; liquids; molecular weight; prediction; solubility; toluene
Abstract:
... Hansen solubility parameters (HSP) aid in the a priori prediction of which low molecular weight molecules have the potential to act as low molecular weight organogelators (LMOGs) and can immobilize certain liquids. The hydrogen-bonding HSP parameter individually has some predictive capacity on whether a molecule will form a gel, solution, or precipitate in a known liquid; in the case of benzene, g ...
DOI:
10.1021/cg500985e
CHORUS:
10.1021/cg500985e

42. Double spin transition in a two dimensional Fe(ii) coordination network

Author:
Maria Książek,   et al.   ; Marek Weselski; Dominika Rokosz; Agnieszka Dreczko; Joachim Kusz; Robert Bronisz;     Show all 6 Authors
Source:
Chemical communications 2018 v.54 no.31 pp. 3895-3898
ISSN:
1364-548X
Subject:
acetonitrile; chemical reactions; deformation; iron; perchlorates; temperature
Abstract:
... In the two dimensional network [Fe(ebbtr)₂(CH₃CN)₂](ClO₄)₂·4CH₃CN a sequence of LS → HS → LS → HS transitions occurs as the exclusive result of the change in temperature. This property results from the extraordinary flexibility/elasticity manifested in the hierarchical arrangement of structural events involving the reorientation of coordinated/noncoordinated molecules as well as with the deformati ...
DOI:
10.1039/c8cc01621f

43. Effect of Cycling Ion and Solvent on the Redox Chemistry of Substituted Quinones and Solvent-Induced Breakdown of the Correlation between Redox Potential and Electron-Withdrawing Power of Substituents

Author:
Maria Strømme,   et al.   ; Huan Wang; Rikard Emanuelsson; Amitava Banerjee; Rajeev Ahuja; Martin Sjödin;     Show all 6 Authors
Source:
Journal of physical chemistry 2020 v.124 no.25 pp. 13609-13617
ISSN:
1932-7455
Subject:
acetonitrile; aqueous solutions; density functional theory; electric power; electrochemistry; electrolytes; energy; models; physical chemistry; quinones; redox potential; solvents; tetrabutylammonium compounds
Abstract:
... Quinones have a capacity for high energy storage and exhibit facile and reversible electrochemistry in several widely different electrolytes. They are, therefore, one of the most popular compounds currently used in organic materials based electrical energy storage. Quinone electrochemistry is, however, strongly affected by the composition of the electrolyte. This report summarizes our systematic i ...
DOI:
10.1021/acs.jpcc.0c03632

44. Efficient atrazine degradation catalyzed by manganese porphyrins: Determination of atrazine degradation products and their toxicity evaluation by human blood cells test models

Author:
Elaine Maria de Souza-Fagundes,   et al.   ; Ana Luísa Almeida Lage; Juliana Martins Ribeiro; Michelle Fernanda Brugnera; Dayse Carvalho da Silva Martins;     Show all 5 Authors
Source:
Journal of hazardous materials 2019 v.378 pp. 120748
ISSN:
0304-3894
Subject:
acetonitrile; atrazine; biomimetics; blood cells; catalysts; catalytic activity; cytochrome P-450; groundwater; humans; hydrogen peroxide; iodobenzenes; manganese; models; oxidants; pollutants; rivers; soil; solvents; toxicity; toxicity testing
Abstract:
... Atrazine (ATZ) is an herbicide that has been considered an environmental pollutant worldwide. ATZ contaminates groundwaters and can persist in soils for up to a year causing several environmental and health problems. This study aimed to investigate ATZ degradation catalyzed by manganese porphyrins as biomimetic cytochrome P450 models. We used PhIO, PhI(OAc)2, H2O2, t-BuOOH, m-CPBA, or Oxone® as ox ...
DOI:
10.1016/j.jhazmat.2019.120748

45. Enantioselective determination of thyroxine enantiomers by ligand-exchange CE with UV absorbance and ICP-MS detection

Author:
Montes-Bayón, Maria,   et al.   ; Kang, Jianzhen; Kutscher, Daniel; Blanco-González, Elisa; Sanz-Medel, Alfredo;     Show all 5 Authors
Source:
Electrophoresis 2009 v.30 no.10 pp. 1774-1782
ISSN:
0173-0835
Subject:
absorbance; acetonitrile; copper; detection limit; drug formulations; electrophoresis; enantiomers; iodine; pH; temperature; thyroxine
Abstract:
... A simple CE method has been developed for the separation and determination of thyroxine (T₄) enantiomers in pharmaceutical formulations. The method was based on ligand-exchange mechanism using a Cu(II)/L-proline complex as chiral selector. The effects of different parameters affecting separation such as chiral selector concentration, organic additive, buffer pH and temperature were investigated. A ...
DOI:
10.1002/elps.200800731

46. Enthalpic versus Entropic Contribution to the Quinone Formal Potential in a Polypyrrole-Based Conducting Redox Polymer

Author:
Strømme Maria,   et al.   ; Emanuelsson Rikard; Huang Hao; Gogoll Adolf; Sjödin Martin;     Show all 5 Authors
Source:
The Journal of Physical Chemistry C 2016 v.120 no.38 pp. 21178-21183
ISSN:
1932-7455
Subject:
acetonitrile; aqueous solutions; electric power; electrochemistry; electrolytes; hydroquinone; pH; physical chemistry; polymers; pyridines
Abstract:
... A conducting redox polymer (CPR) based on pyrrole with a hydroquinone pendant group was synthesized through electropolymerization of the corresponding monomer. The formal potential (E⁰′) in aqueous solution at different pH as well as in MeCN containing equal amounts of pyridinium-triflates and the corresponding free pyridine with different pKₐ was investigated. E⁰′ could be completely recovered in ...
DOI:
10.1021/acs.jpcc.6b05353

47. Evaluation of different QuEChERS procedures for the recovery of selected drugs and herbicides from soil using LC coupled with UV and pulsed amperometry for their detection

Author:
Rosa Maria De Carlo; Maria Concetta Bruzzoniti,   et al.   ; Luca Rivoira; Lorenzo Ciofi; Claudia Ancillotti; Leonardo Checchini; Massimo Del Bubba;     Show all 7 Authors
Source:
Analytical and bioanalytical chemistry 2015 v.407 no.4 pp. 1217-1229
ISSN:
1618-2642
Subject:
acetic acid; acetonitrile; atrazine; bentazon; detection limit; glassy carbon electrode; liquid chromatography; metabolites; microwave treatment; phenytoin; physicochemical properties; rehydration; salts; soil; solid phase extraction
Abstract:
... Seven quick, easy, cheap, effective, rugged and safe (QuEChERS)-based procedures, differing in both the extraction and clean-up steps, were investigated for the recovery of bentazone (BTZ), atrazine (ATZ), carbamazepine (CBZ), phenytoin (PNT) and its metabolite 5-(p-hydroxyphenyl-),5-phenylhydantoin (HPPH) from soil. Target analytes were chosen for their extensive use and/or occurrence in soil, as ...
DOI:
10.1007/s00216-014-8339-x

48. Experimental Design in Ion Chromatography: Effect of the Organic Modifier and Complexing Agent on the Retention of Alkaline and Alkaline Earth Ions

Author:
Maria Anna Maggi,   et al.   ; Fabrizio Ruggieri; Angelo Antonio D’Archivio; Martina Foschi;     Show all 4 Authors
Source:
Chromatographia 2017 v.80 no.6 pp. 853-860
ISSN:
0009-5893
Subject:
acetonitrile; acidification; ammonium; calcium; experimental design; ion exchange chromatography; magnesium; nitric acid; potassium; response surface methodology; sodium
Abstract:
... A Box–Behnken experimental design combined with response surface methodology was applied to investigate the effect of the eluent composition on the retention of common cations in ion chromatography. In particular, we modelled the retention factors of Na⁺, K⁺, NH₄ ⁺, Ca⁺⁺ and Mg⁺⁺ and the chromatogram resolution. Response surfaces were evaluated to assess interactive effects of nitric acid, pyridin ...
DOI:
10.1007/s10337-017-3284-4

49. Experimental Mixture Design as a Tool for the Synthesis of Antimicrobial Selective Molecularly Imprinted Monodisperse Microbeads

Author:
Moreno-Bondi Maria C.,   et al.   ; Benito-Peña Elena; Navarro-Villoslada Fernando; Carrasco Sergio; Jockusch Steffen; Ottaviani M. Francesca;     Show all 6 Authors
Source:
ACS Applied Materials & Interfaces 2015 v.7 no.20 pp. 10966-10976
ISSN:
1944-8252
Subject:
acetonitrile; adsorption; binding sites; chemometrics; electron paramagnetic resonance spectroscopy; enrofloxacin; ethylene glycol; fluoroquinolones; hydrophilicity; light scattering; microbeads; molecular imprinting; nitrogen; particle size; polymerization; polymers; scanning electron microscopy
Abstract:
... The effect of the cross-linker on the shape and size of molecular imprinted polymer (MIP) beads prepared by precipitation polymerization has been evaluated using a chemometric approach. Molecularly imprinted microspheres for the selective recognition of fluoroquinolone antimicrobials were prepared in a one-step precipitation polymerization procedure using enrofloxacin (ENR) as the template molecul ...
DOI:
10.1021/acsami.5b02238

50. Fast analysis of curcuminoids from turmeric (Curcuma longa L.) by high-performance liquid chromatography using a fused-core column

Author:
Maria Angela de Almeida Meireles,   et al.   ; J. Felipe Osorio-Tobón; Pedro I.N. Carvalho; Gerardo Fernández Barbero; Gislaine Chrystina Nogueira; Mauricio Ariel Rostagno;     Show all 6 Authors
Source:
Food chemistry 2016 v.200 pp. 167-174
ISSN:
0308-8146
Subject:
Curcuma longa; acetonitrile; curcumin; detection limit; ethanol; high performance liquid chromatography; methanol; rhizomes; solvents; temperature; turmeric
Abstract:
... The recent development of fused-core technology in HPLC columns is enabling faster and highly efficient separations. This technology was evaluated for the development of a fast method for the analysis of main curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin) present in extracts of turmeric (Curcuma longa L.). A step-by-step strategy was used to optimize temperature (40–55°C), flo ...
DOI:
10.1016/j.foodchem.2016.01.021

51. Fast liquid chromatography/tandem mass spectrometry (highly selective selected reaction monitoring) for the determination of toltrazuril and its metabolites in food

Author:
Maria Teresa Galceran,   et al.   ; Anna Martínez-Villalba; Encarnación Moyano; Claudia P. B. Martins;     Show all 4 Authors
Source:
Analytical and bioanalytical chemistry 2010 v.397 no.7 pp. 2893-2901
ISSN:
1618-2642
Subject:
acetonitrile; atmospheric pressure; detection limit; drugs; ionization; liquid chromatography; meat; metabolites; monitoring; tandem mass spectrometry; toltrazuril
Abstract:
... In this work a fast liquid chromatography (LC)–tandem mass spectrometry (MS/MS) method was developed for the analysis of toltrazuril, a coccidiostatic drug, and its metabolites in meat food products. The applicability of atmospheric pressure chemical ionization (APCI) and heated electrospray ionization in both positive and negative modes was studied. APCI in negative mode provided the best results ...
DOI:
10.1007/s00216-010-3704-x
PubMed:
20658773

52. Fast sample preparation and liquid chromatography-tandem mass spectrometry method for assaying cell lysate acetylcholine

Author:
Hein, Eva-Maria,   et al.   ; Schebb, Nils Helge; Fischer, Daniel; Hayen, Heiko; Krieglstein, Josef; Klumpp, Susanne; Karst, Uwe;     Show all 7 Authors
Source:
Journal of chromatography 2008 v.1183 no.1-2 pp. 100-107
ISSN:
0021-9673
Subject:
acetonitrile; acetylcholine; cultured cells; detection limit; hydrophilic interaction chromatography; tandem mass spectrometry
Abstract:
... A fast liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the analysis of acetylcholine (ACh) in cultured cells. [²H₄]Acetylcholine (ACh-d ₄) was used as an internal standard for calibration. ACh was extracted from the cell lysate with acetonitrile (ACN)/water (80/20, v/v) and the crude extract was analyzed without further purification. Isocratic hydrophilic interac ...
DOI:
10.1016/j.chroma.2008.01.033

53. Fast separation of selective serotonin reuptake inhibitors antidepressants in plasma sample by nonaqueous capillary electrophoresis

Author:
Queiroz, Maria Eugênia Costa,   et al.   ; Catai, Ana Paula Formenton; Carrilho, Emanuel; Lanças, Fernando Mauro;     Show all 4 Authors
Source:
Journal of chromatography 2009 v.1216 no.30 pp. 5779-5782
ISSN:
0021-9673
Subject:
acetonitrile; antidepressants; capillary electrophoresis; chromatography; electrolytes; humans; ionic strength; liquid-liquid extraction; monitoring; pH; phosphoric acid; serotonin
Abstract:
... A simple, fast, and sensitive liquid-liquid extraction method followed by nonaqueous capillary electrophoresis (LLE/NACE) was developed and validated for simultaneous determination of four antidepressants (fluoxetine, sertraline, citalopram and paroxetine) in human plasma. Several experimental separation conditions using aqueous and nonaqueous media separation were tested by varying the electrolyt ...
DOI:
10.1016/j.chroma.2009.05.050

54. Focused Microwave-Assisted Extraction and LC Determination of Ketoprofen in the Presence of Preservatives in a Pharmaceutical Cream Formulation

Author:
Gaudiano, Maria Cristina,   et al.   ; Labbozzetta, Stefano; Valvo, Luisa; Bertocchi, Paola; Alimonti, Stefano; Manna, Livia;     Show all 6 Authors
Source:
Chromatographia 2009 v.69 no.3-4 pp. 365-368
ISSN:
0009-5893
Subject:
acetone; acetonitrile; cream; drug formulations; ketoprofen; liquid chromatography; lysine; microwave treatment; pH; particle size; phosphoric acid; potassium; potassium dihydrogen phosphate; preservatives; screening; solvents; temperature
Abstract:
... A simple and rapid open-vessel focused microwave-assisted extraction (FMAE) method followed by LC analysis was developed for the determination of ketoprofen lysine salt in the presence of methyl p-hydroxybenzoate and propyl p-hydroxybenzoate preservatives in topical cream. Extraction were performed in acetone/potassium dihydrogenphosphate (25 mM, pH 3.0) (70:30 v/v) by reaching a target temperatur ...
DOI:
10.1365/s10337-008-0892-z

55. Fourier Transform Near-Infrared Spectroscopy as a Reliable Method for Quick Real Time Analysis of Complex Samples in Industry

Author:
Brites Alves Ana Maria F.,   et al.   ; Pereira Carlos M. F. S.; Vieira Ana Cristina F.G.A.;     Show all 3 Authors
Source:
Industrial & Engineering Chemistry Research 2013 v.52 no.32 pp. 10873-10879
ISSN:
1520-5045
Subject:
acetone; engineering; methanol; industry; variance; models; acetonitrile; least squares; near-infrared spectroscopy; principal component analysis; water content; distillation; spectral analysis; sulfonic acids; wavelengths; titration; gas chromatography; prediction
Abstract:
... Near-infrared spectroscopy (NIRS) in conjunction with multivariate calibration have proved to be adequate techniques to predict water content as well as methanol concentration in a industrial multicomponent mixture. The calibration models were developed using real industrial complex samples of water, methanol, and several other components in variable but lower concentrations such as sulfonic acids ...
DOI:
10.1021/ie302882g

56. HPLC-potentiometric method for determination of biogenic amines in alcoholic beverages: A reliable approach for food quality control

Author:
Maria C.B.S.M. Montenegro,   et al.   ; Renato L. Gil; Célia G. Amorim; Alberto N. Araújo;     Show all 4 Authors
Source:
Food chemistry 2022 v.372 pp. 131288
ISSN:
0308-8146
Subject:
acetic acid; acetonitrile; beers; cadaverine; electrodes; food chemistry; food quality; ion pair chromatography; methylamine; molecular weight; quality control; red wines; regression analysis; spermine; tyramine; white wines
Abstract:
... Determination of ten biogenic amines in alcoholic beverages by HPLC coupled to a potentiometric detector for food quality control is herein presented. Biogenic amines were separated by ion-pair chromatography on a C18 column using a gradient mobile phase of acetic acid, acetonitrile, and butane-sulfonic acid. Detection was accomplished by a miniaturized amine-selective electrode. The method was va ...
DOI:
10.1016/j.foodchem.2021.131288

57. Hollow mesoporous structured molecularly imprinted polymer as adsorbent in pipette‐tip solid‐phase extraction for the determination of antiretrovirals from plasma of HIV‐infected patients

Author:
Maria José Nunes de Paiva,   et al.   ; Nathália Soares Simões; Hanna Leijoto de Oliveira; Ricky Cássio Santos da Silva; Leila Suleimara Teixeira; Thaís Lorenna Souza Sales; Whocely Victor de Castro; Cristina Sanches; Keyller Bastos Borges;     Show all 9 Authors
Source:
Electrophoresis 2018 v.39 no.20 pp. 2581-2589
ISSN:
0173-0835
Subject:
HIV infections; Human immunodeficiency virus; acetonitrile; adsorbents; antiretroviral agents; benzalkonium chloride; chemical species; electrophoresis; ethylene glycol; high performance liquid chromatography; lamivudine; monitoring; pH; patients; polymers; porous media; solid phase extraction; solvents; statistical analysis; surfactants; therapeutics
Abstract:
... In this work a hollow mesoporous structured molecularly imprinted polymer was synthetized and used as adsorbent in pipette‐tip solid‐phase extraction for the determination of lamivudine (3TC), zidovudine (AZT) and efavirenz (EFZ) from plasma of human immunodeficiency virus (HIV) infected patients by high‐performance liquid chromatography (HPLC). All parameters that influence the recovery of the pi ...
DOI:
10.1002/elps.201800165

58. Improved determination of malonaldehyde by high-performance liquid chromatography with UV detection as 2,3-diaminonaphthalene derivative

Author:
Luca Maria Chiesa,   et al.   ; Sara Panseri; Andrea Brizzolari; Enzo Santaniello; Elena Passerò; Pier Antonio Biondi;     Show all 6 Authors
Source:
Journal of Chromatography B 2015 v.976-977 pp. 91-95
ISSN:
1570-0232
Subject:
absorption; acetonitrile; detection limit; fish fillets; high performance liquid chromatography; liquid-liquid extraction; mackerel; malondialdehyde; pH; system optimization
Abstract:
... A rapid, specific and simple procedure is proposed for the determination of free malonaldehyde (MA) contained in fish tissue. The method is the optimization of the reaction of MA with 2,3-diaminonaphthalene to afford a naphtodiazepinium ion that present a UV absorption at 311nm, useful for MA determination by HPLC with UV detection. The reaction proceeds in the presence of 25% acetonitrile at 37°C ...
DOI:
10.1016/j.jchromb.2014.11.017

59. Improved immobilization and stabilization of lipase from Rhizomucor miehei on octyl-glyoxyl agarose beads by using CaCl2

Author:
Maria D. Rodriguez,   et al.   ; Laura Fernandez-Lopez; Nazzoly Rueda; Rocio Bartolome-Cabrero; Tiago L. Albuquerque; Jose C.S. dos Santos; Oveimar Barbosa; Roberto Fernandez-Lafuente;     Show all 8 Authors
Source:
Process biochemistry 2016 v.51 no.1 pp. 48-52
ISSN:
1359-5113
Subject:
Rhizomucor miehei; acetonitrile; agarose; buffers; calcium; calcium chloride; carboxylic ester hydrolases; manganese chloride; pH; screening
Abstract:
... A strategy to stabilize octyl (OC)-Rhizomucor miehei lipase (RML) and OC-Candida rugosa lipase (CRL) at pH 10 is necessary to take full advantage of the immobilization of these enzymes on OC-glyoxyl (OCGLX) supports. CaCl2 and MnCl2 have been reported to stabilize OC-RM and OC-CRL at pH 5.0 and 7.0. After screening different buffers, 5mM CaCl2 was found to be fully soluble in Gly at pH 10. OC-RML ...
DOI:
10.1016/j.procbio.2015.11.015

60. Improved method for plasma ADMA, SDMA, and arginine quantification by field-amplified sample injection capillary electrophoresis UV detection

Author:
Usai, Maria Franca,   et al.   ; Zinellu, Angelo; Sotgia, Salvatore; Pintus, Gianfranco; Deiana, Luca; Carru, Ciriaco;     Show all 6 Authors
Source:
Analytical and bioanalytical chemistry 2011 v.399 no.5 pp. 1815-1821
ISSN:
1618-2642
Subject:
acetonitrile; ammonia; arginine; capillary electrophoresis; derivatization; detection limit; pH; phosphates; solid phase extraction; statistical analysis
Abstract:
... Here, we describe an easy field-amplified sample injection capillary electrophoresis method with UV detection for the separation and detection of free plasma arginine and dimethylated arginines. The analytes were baseline-separated within 22 min by using 50 mmol/L Tris phosphate pH 2.3 as running buffer. The plasma samples were treated with acetonitrile/ammonia for protein elimination, the superna ...
DOI:
10.1007/s00216-010-4580-0

61. In Situ Determination of Illegal Drugs in Oral Fluid by Portable Capillary Electrophoresis with Deep UV Excited Fluorescence Detection

Author:
Maria Kulp,   et al.   ; Piret Saar-Reismaa; Enn Erme; Merike Vaher; Mihkel Kaljurand; Jekaterina Mazina-Šinkar;     Show all 6 Authors
Source:
Analytical chemistry 2018 v.90 no.10 pp. 6253-6258
ISSN:
1520-6882
Subject:
BTEX (benzene, toluene, ethylbenzene, xylene); acetonitrile; adenosine monophosphate; cannabidiol; capillary electrophoresis; cocaine; detection limit; filters; fluorescence; methamphetamines; music; naphthalene; polymethylmethacrylate; tetrahydrocannabinol; wavelengths; Estonia
Abstract:
... The present study demonstrates the potential of a portable capillary electrophoresis (CE) instrument, coupled to deep UV fluorescence detector (FD) with a 230–255 nm excitation wavelength range, for the determination of the abuse of illegal drugs in oral fluids in situ. CE was introduced in this study due its exceptional power of separation and resolution, short analysis time, and ability for mini ...
DOI:
10.1021/acs.analchem.8b00911

62. In Situ Spectroelectrochemical Studies into the Formation and Stability of Robust Diazonium-Derived Interfaces on Gold Electrodes for the Immobilization of an Oxygen-Tolerant Hydrogenase

Author:
Maria-Andrea Mroginski,   et al.   ; Tomos G. A. A. Harris; Nina Heidary; Jacek Kozuch; Stefan Frielingsdorf; Oliver Lenz; Peter Hildebrandt; Ingo Zebger; Anna Fischer;     Show all 9 Authors
Source:
ACS applied materials & interfaces 2018 v.10 no.27 pp. 23380-23391
ISSN:
1944-8252
Subject:
Cupriavidus necator; acetonitrile; bacteria; diazonium compounds; electrochemistry; electrodes; electron transfer; free radical scavengers; gold; hydrogen; infrared spectroscopy; nanogold; oxidation; phosphates
Abstract:
... Surface-enhanced infrared absorption spectroscopy is used in situ to determine the electrochemical stability of organic interfaces deposited onto the surface of nanostructured, thin-film gold electrodes via the electrochemical reduction of diazonium salts. These interfaces are shown to exhibit a wide electrochemical stability window in both acetonitrile and phosphate buffer, far surpassing the sta ...
DOI:
10.1021/acsami.8b02273

63. In house validation from direct determination of 5-hydroxymethyl-2-furfural (HMF) in Brazilian corn and cane syrups samples by HPLC–UV

Author:
Maria L. Felsner,   et al.   ; Jucimara K. de Andrade; Emy Komatsu; Hélène Perreault; Yohandra R. Torres; Marcos R. da Rosa;     Show all 6 Authors
Source:
Food chemistry 2016 v.190 pp. 481-486
ISSN:
0308-8146
Subject:
acetonitrile; cane syrup; corn; corn syrup; food safety; formic acid; high performance liquid chromatography; hydroxymethylfurfural
Abstract:
... In this work the development and in house validation of the HMF direct determination in corn and cane syrups by HPLC–UV was carried out for the first time. The separation was done with isocratic elution of a mobile phase comprising water (with 0.5% formic acid) and acetonitrile (90:10, v/v) on Phenomenex C18 column (5.0μm, 4.6×150mm), at 30°C, flow rate of 0.8mLmin−1 and detection at 285nm. The va ...
DOI:
10.1016/j.foodchem.2015.05.131

64. Increased Charge Separation Rates with Increasing Donor–Acceptor Distance in Molecular Triads: The Effect of Solvent Polarity

Author:
Wächtler Maria,   et al.   ; Luo Yusen; Barthelmes Kevin; Winter Andreas; Schubert Ulrich S.; Dietzek Benjamin;     Show all 6 Authors
Source:
The Journal of Physical Chemistry C 2017 v.121 no.17 pp. 9220-9229
ISSN:
1932-7455
Subject:
acetonitrile; electron transfer; methylene chloride; models; physical chemistry; solvents
Abstract:
... Distance-dependent electron transfer in donor–spacer–acceptor systems is accepted to occur via two distinct mechanisms, that is, by coherent superexchange or incoherent hopping. In general, the rate of electron transfer (kET) decreases with increasing donor–acceptor distances, irrespective of the actual mechanism being responsible for the process. However, recently Wenger and his group showed that ...
DOI:
10.1021/acs.jpcc.7b02513

65. Indirect determination of aflatoxin B1 in beer via a multi-commuted optical sensor

Author:
Maria Luisa Fernández-de Córdova,   et al.   ; Lucía Molina-García; Antonio Ruiz-Medina;     Show all 3 Authors
Source:
Food additives & contaminants 2012 v.29 no.3 pp. 392-402
ISSN:
1944-0057
Subject:
acetonitrile; aflatoxin B1; beers; carcinogenicity; chromatography; detection limit; fluorescence; hydrophobicity; silica gel; solid phase extraction; spectroscopy; ultraviolet radiation
Abstract:
... This paper reports the determination of aflatoxin B₁ (AFB₁), one of the most carcinogenic substances known. A multi-commuted flow injection–solid phase spectroscopy (FI–SPS) system combined with photochemically induced fluorescence (PIF) was developed, for the first time, for its quantitative determination. A strongly fluorescent degradation product was obtained on-line by irradiation with ultravi ...
DOI:
10.1080/19440049.2011.643244
PubMed:
22264222

66. Influence of salt ions on binding to molecularly imprinted polymers

Author:
Kempe, Maria,   et al.   ; Kempe, Henrik;     Show all 2 Author
Source:
Analytical and bioanalytical chemistry 2010 v.396 no.4 pp. 1599-1606
ISSN:
1618-2642
Subject:
acetonitrile; aqueous solutions; benzylpenicillin; ion exchange; ions; milk; models; molecular imprinting; polymers; propranolol; salts; solid phase extraction; water activity
Abstract:
... Salt ions were found to have an influence on template binding to two model molecularly imprinted polymers (MIPs), targeted to penicillin G and propranolol, respectively, in water-acetonitrile mixtures. Water was detrimental to rebinding of penicillin G whereas propranolol bound in the entire water-acetonitrile range tested. In 100% aqueous solution, 3-M salt solutions augmented the binding of both ...
DOI:
10.1007/s00216-009-3329-0
PubMed:
20012741

67. Influence of soil copper content on the kinetics of thiram adsorption and on thiram leachability from soils

Author:
Maria M. Vidal,   et al.   ; Olga M.S. Filipe; Carina A.E. Costa; Eduarda B.H. Santos;     Show all 4 Authors
Source:
Chemosphere 2013 v.90 pp. 432-440
ISSN:
0045-6535
Subject:
acetonitrile; adsorption; calcium chloride; copper; desorption; equations; immobilization in soil; models; soil; surface water; thiram
Abstract:
... This work aimed to assess the influence of soil copper content on the sorption processes of thiram, a fungicide widely used in agriculture, most of the times together with copper. Two different types of studies were performed: (1) desorption studies of thiram with acetonitrile after batch adsorption equilibration, and ageing of the wet soil for a variable period of time; (2) kinetic studies of thi ...
DOI:
10.1016/j.chemosphere.2012.07.057
PubMed:
22951356

68. Insight into the retention mechanism on immobilized artificial membrane chromatography using two stationary phases

Author:
Maria Ochsenkühn-Petropoulou,   et al.   ; Fotios Tsopelas; Niki Malaki; Theodosia Vallianatou; Marios Chrysanthakopoulos; Demetris Vrakas; Anna Tsantili-Kakoulidou;     Show all 7 Authors
Source:
Journal of chromatography 2015 v.1396 pp. 25-33
ISSN:
0021-9673
Subject:
acetonitrile; chromatography; drugs; electrostatic interactions; lipophilicity; pH; zwitterions
Abstract:
... The retention behavior of sixty structurally diverse drugs on two immobilized artificial membrane (IAM) columns, IAM.PC.MG and IAM.PC.DD2 types, at two pH values, 7.4 and 5.5, was established. Extrapolated to pure aqueous phase retention factors, logkw(IAM), were determined and the role of acetonitrile as organic modifier was explored, considering the relationships with the slopes, S, of the extra ...
DOI:
10.1016/j.chroma.2015.03.060

69. Integrative process to extract chlorophyll and purify rosmarinic acid from rosemary leaves (Rosmarinus officialis)

Author:
Maria N Marques,   et al.   ; Paula GC Gomes; Amanda F Veloso; Isabella FN Maynard; Ranyere Lucena de Souza; Matheus M Pereira; Cleide MF Soares; Álvaro S Lima;     Show all 8 Authors
Source:
Journal of chemical technology and biotechnology 2020 v.95 no.5 pp. 1503-1510
ISSN:
0268-2575
Subject:
Rosmarinus officinalis; acetonitrile; aqueous solutions; biochemical compounds; chlorophyll; ethanol; food industry; leaves; methanol; octoxynol; pharmaceutical industry; potassium phosphates; rosemary; rosmarinic acid; solvents; temperature
Abstract:
... BACKGROUND: Rosemary leaves have been widely employed in the food and pharmaceutical industry due to the presence of important compounds. However, during the extraction process, in addition to the target biomolecules [chlorophyll (Chl), and rosmarinic acid], other components (phenolic compounds) are also extracted. This work focuses on the development of a sequential and selective protocol for the ...
DOI:
10.1002/jctb.6343

70. Intramolecular oxidative palladium-catalyzed diamination reactions of alkenyl sulfamates: an efficient synthesis of [1,2,5]thiadiazolo-fused piperazinones

Author:
Maria A. Chiacchio,   et al.   ; Ugo Chiacchio; Gianluigi Broggini; Roberto Romeo; Silvia Gazzola; Salvatore V. Giofrè; Bartolo Gabriele; Raffaella Mancuso; Giuseppe Floresta; Chiara Zagni;     Show all 10 Authors
Source:
RSC advances 2016 v.6 no.62 pp. 57521-57529
ISSN:
2046-2069
Subject:
acetonitrile; amination; catalytic activity; palladium; sulfamates
Abstract:
... A palladium-catalyzed diamination domino process of sulfamates arising from glycine allylamides is reported. The reaction leads to the formation of [1,2,5]thiadiazolo-fused piperazinones. The essential feature of the synthetic route is the use of PdCl₂(MeCN)₂/CuBr₂, as a catalytic system which promotes the second amination process, leading to the bicycle ring-fused compounds in good yields. ...
DOI:
10.1039/c6ra13141g

71. Inverse dispersive liquid-liquid microextraction(I-DLLME) for the simultaneous and green preconcentration of DEET and permethrin from freshwater

Author:
Maria Lourdes Leite de Moraes,   et al.   ; Camila Parente; Natália Torgan; Leandro Augusto Calixto; Sherlan Guimarães Lemos; Elma Neide Vasconcelos Martins Carrilho; Geórgia Labuto;     Show all 7 Authors
Source:
Sustainable chemistry and pharmacy 2022 v.27 pp. 100669
ISSN:
2352-5541
Subject:
acetonitrile; analytical chemistry; chloroform; deet; diodes; dispersants; freshwater; green chemistry; high performance liquid chromatography; liquid-phase microextraction; pH; permethrin
Abstract:
... Global warming can stimulate mosquitoes to proliferate and the consumption of repellents and insecticides. These formulations can have N,N-diethyl-m-toluamide (DEET) and permethrin, which were reported in water bodies, requiring sensitive methods for quantification. We propose changing the dispersive liquid-liquid microextraction (DLLME), a green extraction technique, by inverting the sequence of ...
DOI:
10.1016/j.scp.2022.100669

72. Investigations into the separation behaviour of perfluorinated C8 and undecanoic acid modified silica hydride stationary phases

Author:
Maria T. Matyska,   et al.   ; Chadin Kulsing; Yuanzhong Yang; Roshanak Sepehrifar; Michael Lim; Joshua Toppete; Joseph J. Pesek; Reinhard I. Boysen; Milton T.W. Hearn;     Show all 9 Authors
Source:
Analytica chimica acta 2016 v.916 pp. 102-111
ISSN:
0003-2670
Subject:
acetonitrile; analytical chemistry; energy; hydrides; pH; silica; solvents; zeta potential
Abstract:
... In this study, the surface charge properties of perfluorinated C8 (PerfluoroC8) and undecanoic acid (UDA) modified silica hydride stationary phases have been investigated. The zeta potential values of these stationary phases were measured in aqueous/acetonitrile mobile phases of different pH, buffer concentrations and acetonitrile contents. The retention behaviour of several basic, acidic and neut ...
DOI:
10.1016/j.aca.2016.02.013

73. Ion-Pair Chromatography Coupled to Inductively Coupled Plasma–Mass Spectrometry (IPC-ICP-MS) as a Method for Thiomolybdate Speciation in Natural Waters

Author:
Reithmaier Gloria Maria Susanne,   et al.   ; Lohmayer Regina; Bura-Nakić Elvira; Planer-Friedrich Britta;     Show all 4 Authors
Source:
Analytical chemistry 2015 v.87 no.6 pp. 3388-3395
ISSN:
1520-6882
Subject:
acetonitrile; anaerobic conditions; atomic absorption spectrometry; carbon; detection limit; hydrolysis; ion pair chromatography; ionic strength; isopropyl alcohol; molybdenum; pH; sediments; solvents; sulfides; thiomolybdates
Abstract:
... Molybdenum precipitates preferentially under reducing conditions; therefore, its occurrence in sediment records is used as an indicator of paleoredox conditions. Although thiomolybdates (MoO₄–ₓSₓ²– with x = 1–4) supposedly are necessary intermediates in the process of molybdenum precipitation under anoxic conditions, there is no information about their abundance in natural environments, because of ...
DOI:
10.1021/ac5046406

74. Ion-molecule adduct formation in tandem mass spectrometry

Author:
Maria Teresa Galceran,   et al.   ; Élida Alechaga; Encarnación Moyano;     Show all 3 Authors
Source:
Analytical and bioanalytical chemistry 2016 v.408 no.4 pp. 1269-1277
ISSN:
1618-2642
Subject:
acetonitrile; drugs; gases; heterocyclic amines; ionization; ions; levamisole; methanol; monitoring; solvents; spectrometers; tandem mass spectrometry
Abstract:
... Nowadays most LC-MS methods rely on tandem mass spectrometry not only for quantitation and confirmation of compounds by multiple reaction monitoring (MRM), but also for the identification of unknowns from their product ion spectra. However, gas-phase reactions between charged and neutral species inside the mass analyzer can occur, yielding product ions at m/z values higher than that of the precurs ...
DOI:
10.1007/s00216-015-9237-6

75. Ionic Liquid-Induced Local Charge Compensation: Effects on Back Electron-Transfer Rates in Dye-Sensitized TiO2 Thin Films

Author:
Abrahamsson Maria,   et al.   ; Saavedra Becerril Valeria; Franchi Daniele;     Show all 3 Authors
Source:
The Journal of Physical Chemistry C 2016 v.120 no.36 pp. 20016-20023
ISSN:
1932-7455
Subject:
absorption; acetonitrile; cations; dyes; electron transfer; electrons; ionic liquids; ligands; oxidation; photovoltaic cells; thiocyanates; titanium dioxide
Abstract:
... The effect of ionic liquid electrolytes on back electron-transfer rates for dye-sensitized TiO₂ thin films was investigated using microsecond–millisecond transient absorption. For D35/TiO₂ and [Ru(dcb)₃]²⁺/TiO₂ in electrolytes based on 1-alkyl-3-methyl-imidazolium hexafluorophosphate, significantly slower back electron-transfer rates, compared to those observed in neat acetonitrile (CH₃CN) and LiC ...
DOI:
10.1021/acs.jpcc.6b06088

76. Keys for the Existence of Stable Dimers of Bis-tetrathiafulvalene (bis-TTF)-Functionalized Molecular Clips Presenting [TTF]•+···[TTF]•+ Long, Multicenter Bonds at Room Temperature

Author:
Fumanal Maria,   et al.   ; Capdevila-Cortada Marçal; Miller Joel S.; Novoa Juan J.;     Show all 4 Authors
Source:
Journal of the American Chemical Society 2013 v.135 no.37 pp. 13814-13826
ISSN:
1520-5126
Subject:
absorption; acetonitrile; ambient temperature; geometry; solvents; spectral analysis; van der Waals forces; zwitterions
Abstract:
... A systematic theoretical and computational investigation is performed to determine the keys governing the existence, in acetonitrile solutions, of dimers of bis-tetrathiafulvalene (bis-TTF)-functionalized diphenylglycoluril molecular clips (clip₂ⁿ⁺) that are stable at room temperature for n ≤ 4. Although the experimental structure of these dimers in solution is unknown, electronic absorption studi ...
DOI:
10.1021/ja405352p

77. LC Evaluation of Intestinal Transport of Praziquantel

Author:
Gremião, Maria Palmira D.,   et al.   ; Cinto, Priscila O.; Souza, Ana Luiza Ribeiro; Lima, Andréa C.; Chaud, Marco V.;     Show all 5 Authors
Source:
Chromatographia 2009 v.69 no.2 pp. 213-217
ISSN:
0009-5893
Subject:
absorbance; absorption; acetonitrile; chromatography; detection limit; drugs; gastrointestinal system; models; monitoring; praziquantel; rats; solubility
Abstract:
... Praziquantel (PZQ) is a highly lipophilic drug with low aqueous solubility. Despite this, it is well absorbed from the gastrointestinal tract. In this study, a simple LC method was developed and validated, in order to monitor the concentration of PZQ in TC-199 buffer in vitro, in the rat everted gut sac absorption model. PZQ was analyzed by a reversed-phase LC method with an isocratic mobile phase ...
DOI:
10.1365/s10337-009-1019-x

78. LC-MS Identification and Quantification of Phenolic Compounds in Solid Residues from the Essential Oil Industry

Author:
Maria Irakli,   et al.   ; Adriana Skendi; Elisavet Bouloumpasi; Paschalina Chatzopoulou; Costas G. Biliaderis;     Show all 5 Authors
Source:
Antioxidants 2021 v.10 no.12 pp. -
ISSN:
2076-3921
Subject:
Melissa officinalis; Mentha spicata; Satureja; absorption; acetonitrile; calibration; distillation; diterpenoids; fats and oils industry; flavonoids; formic acid; liquid chromatography; mass spectrometry; oregano; quality control; rosemary; sage; salicylic acid; solid wastes
Abstract:
... Plant solid residues obtained from the essential oil industry represent a rich source of phenolic compounds with bioactive properties to be used in the food and pharmaceutical industries. A selective and sensitive liquid chromatography-mass spectrometry (LC-MS) method was developed for the simultaneous determination of phenolic compounds in solid residues of the Lamiaceae family plants. A total of ...
DOI:
10.3390/antiox10122016

79. LC-MS determination of steroidal glycosides from Dioscorea deltoidea Wall cell suspension culture: Optimization of pre-LC-MS procedure parameters by Latin Square design

Author:
Maria Titova,   et al.   ; Boris Sarvin; Elizaveta Fedorova; Oleg Shpigun; Mikhail Nikitin; Dmitry Kochkin; Igor Rodin; Andrey Stavrianidi;     Show all 8 Authors
Source:
Journal of chromatography 2018 v.1080 pp. 64-70
ISSN:
1570-0232
Subject:
Dioscorea deltoidea; acetonitrile; cell suspension culture; experimental design; glycosides; high performance liquid chromatography; mass spectrometry; solvents
Abstract:
... In this paper, the ultrasound assisted extraction method for isolation of steroidal glycosides from D. deltoidea plant cell suspension culture with a subsequent HPLC-MS determination was developed. After the organic solvent was selected via a two-factor experiment the optimization via Latin Square 4 × 4 experimental design was carried out for the following parameters: extraction time, organic solv ...
DOI:
10.1016/j.jchromb.2018.02.012

80. Life cycle assessment of vitamin D3 synthesis: from batch to photo-high p,T

Author:
Olivia Maria Morales-Gonzalez,   et al.   ; Marc Escribà-Gelonch; Volker Hessel;     Show all 3 Authors
Source:
international journal of life cycle assessment 2019 v.24 no.12 pp. 2111-2127
ISSN:
0948-3349
Subject:
acetonitrile; batch systems; benzene; cholecalciferol; computer software; cradle-to-gate; crystallization; environmental impact; isopropyl alcohol; patents; photoirradiation; photons; solvents; temperature
Abstract:
... PURPOSE: Novel process windows allow the development of faster, flexible, and greener processes. Therefore, novel process windows were applied to develop a greener process for the synthesis of vitamin D₃. In this study the environmental impacts of several batch pathways to obtain vitamin D₃ are benchmarked against the continuous microflow process, where novel process windows such as high temperatu ...
DOI:
10.1007/s11367-019-01634-6

81. Liquid-Liquid extraction of phenolic compounds in systems based on acetonitrile + water + polyvinylpyrrolidone at 298.15 K

Author:
Camila Maria de Souza D’Anzicourt,   et al.   ; Bruno Sales Oliveira; Cleide Mara Faria Soares; Ranyere Lucena de Souza; Álvaro Silva Lima;     Show all 5 Authors
Source:
Data in Brief 2018 v.20 pp. 2045-2053
ISSN:
2352-3409
Subject:
acetonitrile; chlorides; cyanidin; gallic acid; liquid-liquid extraction; polyvinylpyrrolidone; quercetin
Abstract:
... This paper contains data related to the research paper entitled “Organic two-phase system based on acetonitrile + water + polyvinylpyrrolidone, a novel concept of liquid–liquid equilibrium: phase diagrams and phenolic compounds partitioning”. Data of phase equilibrium were obtained using the cloud point method. After this step, some blending points were chosen to perform the phenolic compounds par ...
DOI:
10.1016/j.dib.2018.09.067

82. Mechanism and Kinetics of Lipase-Catalyzed Polycondensation of Glycerol and Sebacic Acid: Influence of Solvent and Temperature

Author:
Maria Isabel Felisberti,   et al.   ; Giovanni Bortoloni Perin;     Show all 2 Author
Source:
Biomacromolecules 2022 v.23 no.7 pp. 2968-2975
ISSN:
1526-4602
Subject:
acetone; acetonitrile; carboxylic acids; catalytic activity; condensation reactions; esterification; glycerol; hydrogen; molecular weight; polymerization; polymers; reaction kinetics; regioselectivity; solvents; temperature
Abstract:
... The mechanism for theCandida antacticalipase B (CALB)-catalyzed polycondensation of glycerol and sebacic acid in polar solvents was proposed based on the profile of formation and consumption of the glyceridic species in the reaction media and on the occurrence of the acyl migration reaction. The acyl migration is mainly responsible for the esterification of the secondary hydroxyl of glycerol and i ...
DOI:
10.1021/acs.biomac.2c00458

83. Methodology for a rapid and simultaneous determination of total cysteine, homocysteine, cysteinylglycine and glutathione in plasma by isocratic RP-HPLC

Author:
Maria Leonor Pavão,   et al.   ; Rita Ferin; José Baptista;     Show all 3 Authors
Source:
Journal of chromatography 2012 v.911 no. pp. 15-20
ISSN:
1570-0232
Subject:
acetonitrile; biomarkers; blood plasma; cysteine; fluorescence; glutathione; homocysteine; humans; phosphates; reversed-phase high performance liquid chromatography; screening; thiols
Abstract:
... Alterations in the plasma aminothiols levels can be considered as important biomarkers for the diagnosis and screening of several human disorders, namely cardiovascular diseases. We aimed to optimize a rapid, sensitive and accurate RP-HPLC methodology with fluorescence detection, for the simultaneous determination of the total concentrations of cysteine, homocysteine, cysteinylglycine and glutathi ...
DOI:
10.1016/j.jchromb.2012.10.022

84. Microextraction technique associated with gas chromatography–mass spectrometry for determining pesticide residues in urine

Author:
Maria Eliana L. R. de Queiroz,   et al.   ; Thaís L. R. Silva; André Fernando de Oliveira; Alessandra A. Z. Rodrigues; Antônio Augusto Neves; Patrícia A. F. Vieira; José Humberto de Queiroz; Verônica O. de P. Barbosa;     Show all 8 Authors
Source:
Journal of environmental science and health 2022 v.57 no.3 pp. 165-175
ISSN:
1532-4109
Subject:
acetonitrile; alachlor; aldrin; bifenthrin; chemical species; chlorpyrifos; detection limit; dieldrin; endrin; environmental science; gas chromatography-mass spectrometry; humans; lindane; liquid-phase microextraction; permethrin; solvents; urine; Brazil
Abstract:
... Urine is one of the biological matrices most used for detecting human contamination, as it is representative and easily obtained via noninvasive sampling. This study proposes a fast, accurate, and ecological method based on liquid–liquid microextraction with low-temperature partition (μLLE/LTP). It was validated to determine nine pesticides (lindane, alachlor, aldrin, chlorpyrifos, dieldrin, endri ...
DOI:
10.1080/03601234.2022.2038505

85. Molecularly imprinted pipette-tip solid phase extraction for selective determination of fluoroquinolones in human urine using HPLC-DAD

Author:
Anny Talita Maria da Silva,   et al.   ; Hanna Leijoto de Oliveira; Sara da Silva Anacleto; Arnaldo César Pereira; Warley de Souza Borges; Eduardo Costa Figueiredo; Keyller Bastos Borges;     Show all 7 Authors
Source:
Journal of chromatography 2016 v.1033-1034 pp. 27-39
ISSN:
1570-0232
Subject:
acetonitrile; ciprofloxacin; excretion; high performance liquid chromatography; humans; ionic strength; molecular imprinting; norfloxacin; pH; phosphoric acid; polymers; solid phase extraction; solvents; triethylamine; urine; washing
Abstract:
... A simple method using HPLC-DAD was developed for the determination of fluoroquinolones in human urine including ciprofloxacin (CIPRO), enrofloxacino (ENRO), marbofloxacino (MARBO) and norfloxacin (NOR). In addition, it was studied the extraction of fluoroquinolones in human urine samples using pipette tip-based molecularly imprinted polymers solid phase extraction (PT-MIPs-SPE). With the goal of f ...
DOI:
10.1016/j.jchromb.2016.08.008

86. Molecularly imprinted polymer beads for nicotine recognition prepared by RAFT precipitation polymerization: a step forward towards multi-functionalities

Author:
Maria Ahlm Mattebjerg,   et al.   ; Tongchang Zhou; Lars Jørgensen; Ioannis S. Chronakis; Lei Ye;     Show all 5 Authors
Source:
RSC advances 2014 v.4 no.57 pp. 30292-30299
ISSN:
2046-2069
Subject:
acetonitrile; fluorescent dyes; hydrophilicity; molecular imprinting; nicotine; polymerization; polymers; thiols
Abstract:
... A nicotine imprinted polymer was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization using methacrylic acid (MAA) as a functional monomer. The resulting molecularly imprinted polymers were monodispersed beads with an average diameter of 1.55 μm. The molecular selectivity of the imprinted polymer beads was evaluated by studying the uptake of nicotine and its struct ...
DOI:
10.1039/c4ra04741a

87. Molecularly imprinted polymers for cleanup and selective extraction of curcuminoids in medicinal herbal extracts

Author:
Maria C. Moreno-Bondi,   et al.   ; Meyliana Wulandari; Javier L. Urraca; Ana B. Descalzo; M. Bachri Amran;     Show all 5 Authors
Source:
Analytical and bioanalytical chemistry 2015 v.407 no.3 pp. 803-812
ISSN:
1618-2642
Subject:
acetonitrile; ammonium acetate; binding capacity; curcumin; dimethyl sulfoxide; ethylene glycol; fluorescence; high performance liquid chromatography; methanol; models; molecular imprinting; pH; polymers; solid phase extraction; sorption isotherms; washing
Abstract:
... This paper describes the synthesis of novel molecularly imprinted polymers (MIPs), prepared by a noncovalent imprinting approach, for cleanup and preconcentration of curcumin (CUR) and bisdemethoxycurcumin (BDMC) from medicinal herbal extracts and further analysis by high-performance liquid chromatography with fluorescence detection (HPLC-FLD). Two molecular mimics, a mixture of reduced BDMCs and ...
DOI:
10.1007/s00216-014-8011-5

88. Moxidectin residues in lamb tissues: Development and validation of analytical method by UHPLC-MS/MS

Author:
Maria A.M. Fernandes,   et al.   ; Michelle Del Bianchi A. Cruz; Patricia A. de C. Braga; Alda L.G. Monteiro; Daniela Daniel; Felix G.R. Reyes;     Show all 6 Authors
Source:
Journal of chromatography 2018 v.1072 pp. 390-396
ISSN:
1570-0232
Subject:
acetonitrile; ammonium; detection limit; formates; formic acid; kidneys; liquid chromatography; liver; monitoring; moxidectin; muscles; pharmacokinetics; tandem mass spectrometry; tissues
Abstract:
... The development and validation of a throughput method for the quantitation of moxidectin residues in lamb target tissues (muscle, kidney, liver and fat) was conducted using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS). To achieve higher recovery of the analyte from the matrices, a modified QuEChERS method was used for sample preparation. The chromatographic s ...
DOI:
10.1016/j.jchromb.2017.11.041

89. Multi-residue and multi-class determination of antibiotics in gilthead sea bream (Sparus aurata) by ultra high-performance liquid chromatography-tandem mass spectrometry

Author:
Maria da Conceição Castilho,   et al.   ; Andreia Freitas; Sara Leston; João Rosa; Jorge Barbosa; Paulo Rema; Miguel Ângelo Pardal; Fernando Ramos;     Show all 8 Authors
Source:
Food additives & contaminants 2014 v.31 no.5 pp. 817-826
ISSN:
1944-0057
Subject:
Sparus aurata; acetic acid; acetonitrile; chloramphenicol; fish culture; macrolides; maximum residue limits; muscles; penicillins; quinolones; sulfonamides; tandem mass spectrometry; tetracyclines; trimethoprim; ultra-performance liquid chromatography
Abstract:
... This paper describes a method for the determination of 41 antibiotics from seven different classes in gilthead sea bream (Sparus aurata) by ultra-high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol were simultaneously determined. Fourteen procedures for sample treatment ...
DOI:
10.1080/19440049.2014.891764

90. Multiclass determination of endocrine disruptors in urine by hollow fiber microporous membrane and liquid chromatography

Author:
Maria Eduarda Pierri,   et al.   ; Lucas Morés; Gabrieli Bernardi; Eduardo Carasek;     Show all 4 Authors
Source:
Analytical biochemistry 2022 v.652 pp. 114725
ISSN:
0003-2697
Subject:
acetonitrile; benzophenones; bisphenol A; carbofuran; desorption; diazepam; diclofenac; estradiol; humans; ibuprofen; liquid chromatography; methanol; microporous membranes; pH; parathion-methyl; porous media; solvents; urine
Abstract:
... A simple and rapid methodology was developed using hollow fiber membrane microporous and a 96-well plate system for a high throughput multiclass determination of endocrine disruptors in human urine (diclofenac, diazepam, carbamazepine, ibuprofen, naproxen, carbofuran, methyl parathion, 17-α-ethynyl estradiol, bisphenol A and benzophenone). The quantification and detection of the chemicals were car ...
DOI:
10.1016/j.ab.2022.114725

91. Multiresidue Screening Method for Detection of Benzimidazoles and their Metabolites in Liver and Muscle by High-Performance Liquid Chromatography: Method Development and Validation According to Commission Decision 2002/657/EC

Author:
Maria Cesarina Abete,   et al.   ; Marilena Gili; Marino Prearo; Paola Stella; Federica Ostorero;     Show all 5 Authors
Source:
Italian journal of food safety 2014 v.3 no.1 pp. -
ISSN:
2239-7132
Subject:
acetonitrile; albendazole; ammonium hydroxide; animal-based foods; benzimidazole; cation exchange; cattle; detectors; drug residues; fenbendazole; fish; flubendazole; fluorescence; food safety; hexane; high performance liquid chromatography; horses; hydrochloric acid; liver; mebendazole; metabolites; muscles; oxfendazole; oxibendazole; poultry; qualitative analysis; rabbits; screening; sheep; solid phase extraction; solvents; swine; thiabendazole; veterinary drugs
Abstract:
... The use of veterinary drugs may cause the presence of residues in food of animal origin if appropriate withdrawal periods are not respected. A high-performance liquid chromatography (HPLC) method has been developed for the simultaneous detection of 11 benzimidazole residues, including metabolites – albendazole, albendazole sulphoxide, albendazole sulphone, fenbendazole, fenbendazole sulphoxide (ox ...
DOI:
10.4081/ijfs.2014.1640
PubMed:
27800310
PubMed Central:
PMC5076660

92. Multitoxin immunoaffinity analysis of aflatoxins and ochratoxin A in spices

Author:
Maria Helena Iha,   et al.   ; Matheus Leandro Rodrigues; Mary Wat Trucksess;     Show all 3 Authors
Source:
Journal of food safety 2021 v.41 no.5 pp. e12921
ISSN:
0149-6085
Subject:
acetonitrile; black pepper; detection limit; fluorescence; food safety; methanol; nutmeg; ochratoxin A; paprika; reversed-phase liquid chromatography; standard deviation; turmeric
Abstract:
... A multitoxin method for aflatoxins (AFs) and ochratoxin A (OTA) was modified and validated to analyze black pepper, colorífico, nutmeg, paprika, and turmeric. The method consisted of acetonitrile, NaHCO₃ and methanol extraction solution, multimycotoxin immunoaffinity column purification and isolation, reversed‐phase liquid chromatography separation, and fluorescence detection. The limit of detecti ...
DOI:
10.1111/jfs.12921

93. Novel alanines bearing a heteroaromatic side chain: synthesis and studies on fluorescent chemosensing of metal cations with biological relevance

Author:
Maria Manuela M. Raposo,   et al.   ; Rosa Cristina M. Ferreira; Susana P. G. Costa;     Show all 3 Authors
Source:
Amino acids 2018 v.50 no.6 pp. 671-684
ISSN:
0939-4451
Subject:
acetonitrile; alanine; cations; cobalt; copper; fluorescence; fluorometry; metal ions; nickel; peptides; proteins; thiophene; zinc
Abstract:
... A family of novel thienylbenzoxazol-5-yl-L-alanines, consisting of an alanine core bearing a benzoxazole at the side chain with a thiophene ring at position 2, substituted with different (hetero)aryl substituents, was synthesised to study the tuning of the photophysical and chemosensory properties of the resulting compounds. These novel heterocyclic alanines 3a–f and a series of structurally relat ...
DOI:
10.1007/s00726-018-2549-z

94. Novel approach for purification of major betalains using flash chromatography and comparison of radical scavenging and antioxidant activities

Author:
Maria J. Frutos,   et al.   ; Ganwarige Sumali N. Fernando; Natalia N. Sergeeva; Lisa J. Marshall; Christine Boesch;     Show all 5 Authors
Source:
Food chemistry 2022 v.385 pp. 132632
ISSN:
0308-8146
Subject:
acetonitrile; antioxidants; betalains; food chemistry; formic acid; raw materials; reversed-phase high performance liquid chromatography
Abstract:
... The present study focused on the development of a new purification protocol suitable for betanin and other major betalains, vulgaxanthin I, indicaxanthin and neobetanin, using flash chromatography which is a convenient and fast method to isolate unstable materials. Following preliminary tests, a gradient procedure using 0–60% acetonitrile, with 0.1% (v/v) formic acid as mobile phase, was selected ...
DOI:
10.1016/j.foodchem.2022.132632

95. On-line SPE–UHPLC method using fused core columns for extraction and separation of nine illegal dyes in chilli-containing spices

Author:
Maria A. Khalikova,   et al.   ; Dalibor Šatínský; Tereza Šmidrkalová; Petr Solich;     Show all 4 Authors
Source:
Talanta 2014 v.130 pp. 433-441
ISSN:
0039-9140
Subject:
European Union; Sudan dyes; acetonitrile; chromatography; detection limit; quantitative analysis; sorbents; spices; statistical analysis; temperature
Abstract:
... The presented work describes the development of a simple, fast and effective on-line SPE–UHPLC–UV/vis method using fused core particle columns for extraction, separation and quantitative analysis of the nine illegal dyes, most frequently found in chilli-containing spices. The red dyes Sudan I–IV, Sudan Red 7B, Sudan Red G, Sudan Orange G, Para Red, and Methyl Red were separated and analyzed in les ...
DOI:
10.1016/j.talanta.2014.07.038

96. Optimal Concentration of Organic Solvents to be Used in the Broth Microdilution Method to Determine the Antimicrobial Activity of Natural Products Against Paenibacillus Larvae

Author:
Maria Celeste Pellegrini; Rosa Maria Alonso-Salces,   et al.   ; Noelia Melina Cugnata; Elisa Guaspari; Sandra Rosa Fuselli;     Show all 5 Authors
Source:
Journal of apicultural science 2017 v.61 no.1 pp. 37-53
ISSN:
2299-4831
Subject:
American foul brood; Apis mellifera; Paenibacillus larvae; acetonitrile; antimicrobial properties; bacteria; beehives; butanol; byproducts; dimethyl sulfoxide; essential oils; ethanol; honey; honey bees; methanol; minimum inhibitory concentration; molds (fungi); solvents; viability
Abstract:
... American Foulbrood (AFB) is a bacterial disease, caused by Paenibacillus larvae, that affects honeybees (Apis mellifera). Alternative strategies to control AFB are based on the treatment of the beehives with antimicrobial natural substances such as extracts, essential oils and/or pure compounds from plants, honey by-products, bacteria and moulds. The broth microdilution method is currently one of ...
DOI:
10.1515/jas-2017-0004

97. Optimisation of a sample preparation method for the determination of fumonisin B1 in rice

Author:
Maria Isabel Rodrigues; Célia Maria de Sylos,   et al.   ; Mateus Henrique Petrarca; Elizeu Antonio Rossi;     Show all 4 Authors
Source:
Food chemistry 2014 v.158 pp. 270-277
ISSN:
0308-8146
Subject:
acetic acid; acetonitrile; aqueous solutions; cost effectiveness; derivatization; detection limit; diatomaceous earth; experimental design; fumonisin B1; rice; sodium chloride; sodium sulfate; Brazil
Abstract:
... A simple, rapid and cost-effective sample preparation method for the determination of fumonisin B1 in rice was optimised using a strategy of sequential experimental designs. Initially, a Plackett–Burman design was applied to select the statistically significant variables for the determination of fumonisin B1, and then, a central composite rotatable design was used to define the optimal conditions ...
DOI:
10.1016/j.foodchem.2014.02.126

98. Optimization and development of a high‐performance liquid chromatography method for the simultaneous determination of vitamin E and carotenoids in tomato fruits

Author:
Maria Irakli,   et al.   ; Paschalina Chatzopoulou; Kalliopi Kadoglidou; Nektaria Tsivelika;     Show all 4 Authors
Source:
Journal of separation science 2016 v.39 no.17 pp. 3348-3356
ISSN:
1615-9306
Subject:
acetonitrile; antioxidants; beta-carotene; cherries; detection limit; detectors; ethyl acetate; fluorescence; fruits; hexane; high performance liquid chromatography; lutein; lycopene; methanol; methylene chloride; phytopharmaceuticals; pulp; solid phase extraction; solvents; tocopherols; tocotrienols; tomatoes; zeaxanthin
Abstract:
... A simple and reliable high‐performance liquid chromatography method was developed and validated for the simultaneous determination of lipophilic antioxidants in tomato fruits using C₃₀ column operated at 15°C and a gradient mobile phase based on acetonitrile/methanol/dichloromethane in a total run time of 30 min. Diode array and fluorescence detectors were used respectively for the detection of ca ...
DOI:
10.1002/jssc.201600491

99. Optimized and validated high‐performance liquid chromatography method for the determination of deoxynivalenol and aflatoxins in cereals

Author:
Maria N. Irakli; Maria D. Papageorgiou,   et al.   ; Adriana Skendi;     Show all 3 Author
Source:
Journal of separation science 2016 v.39 no.8 pp. 1425-1432
ISSN:
1615-9306
Subject:
acetonitrile; aflatoxins; corn; deoxynivalenol; fluorescence; high performance liquid chromatography; humans; methanol; response surface methodology; solid phase extraction; Greece
Abstract:
... A simple, sensitive and accurate analytical method was optimized and developed for the determination of deoxynivalenol and aflatoxins in cereals intended for human consumption using high‐performance liquid chromatography with diode array and fluorescence detection and a photochemical reactor for enhanced detection. A response surface methodology, using a fractional central composite design, was ca ...
DOI:
10.1002/jssc.201501217

100. Phospholipid removal combined with a semi-automated 96-well SPE application for determination of budesonide in human plasma with LC–MS/MS

Author:
Maria Andersson,   et al.   ; Karin Nilsson; Olof Beck;     Show all 3 Authors
Source:
Journal of Chromatography B 2014 v.970 pp. 31-35
ISSN:
1570-0232
Subject:
acetonitrile; automation; formic acid; humans; ionization; liquid chromatography; monitoring; pharmacokinetics; phospholipids; quality control; solid phase extraction; tandem mass spectrometry
Abstract:
... A semi-automated method for quantification of budesonide in human plasma was developed, validated, and applied for high-volume analysis of samples in connection with a pharmacokinetic study. Protein and phospholipid removal was performed using an Ostro 96-well filter plate and subsequently combined with C18 solid-phase extraction on a Hamilton Microlab STARlet automation robot. The final extracts ...
DOI:
10.1016/j.jchromb.2014.08.035