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1. Electron-impact and glow-discharge ionization LC-MS analysis of green tea tincture

Author:
Venzie, Jacob L.; Castro, Joaudimir; Balarama Krishna, M. V.; Nelson, Dwella M.; Marcus, R. Kenneth
Source:
Analytical and bioanalytical chemistry 2007 v.387 no.1 pp. 321-333
ISSN:
1618-2642
Subject:
caffeine; catechin; detection limit; epicatechin; epigallocatechin; green tea; high performance liquid chromatography; ionization; ions; spectrometers
Abstract:
... A liquid chromatography-particle-beam mass spectrometer (LC-PB/MS) with interchangeable electron-impact (EI) and glow-discharge (GD) ion sources was evaluated for future application in analysis of botanical extracts. In this work a green tea tincture was characterized for a series of catechin components (catechin, epicatechin, epigallocatechin, and epigallocatechin gallate (EGCG)) and caffeine. Sp ...
DOI:
10.1007/s00216-006-0934-z
PubMed:
17139484

2. Development of a methodology utilizing gas chromatography ion-trap tandem mass spectrometry for the determination of low levels of caffeine in surface marine and freshwater samples

Author:
Sergei S. Verenitch; Asit Mazumder
Source:
Analytical and bioanalytical chemistry 2008 v.391 no.7 pp. 2635
ISSN:
1618-2642
Subject:
caffeine; coasts; detection limit; dissociation; freshwater; gas chromatography; ionization; ions; isotope dilution technique; lakes; monitoring; residential density; tandem mass spectrometry; British Columbia
Abstract:
... A methodology for monitoring low level of caffeine in aqueous samples via gas chromatography coupled with an ion-trap tandem mass spectrometry detection system (IT-MS/MS) was developed. Four IT-MS/MS operating parameters, including the collision-induced dissociation (CID) voltage, the excitation time (ET), the isolation time (IT) and the maximum ionization time (MIT) were optimized in order to max ...
DOI:
10.1007/s00216-008-2174-x
PubMed:
18535819

3. Impact of solvent conditions on separation and detection of basic drugs by micro liquid chromatography–mass spectrometry under overloading conditions

Author:
Birthe Schubert; Herbert Oberacher
Source:
Journal of chromatography 2011 v.1218 no.22 pp. 3413-3422
ISSN:
0021-9673
Subject:
acetic acid; caffeine; cocaine; codeine; diazepam; forensic sciences; formic acid; haloperidol; hydrophobicity; ionization; liquid chromatography; mass spectrometry; morphine; nicotine; polar compounds; quantitative analysis; solvents
Abstract:
... In this study the impact of solvent conditions on the performance of μLC/MS for the analysis of basic drugs was investigated. Our aim was to find experimental conditions that enable high-performance chromatographic separation particularly at overloading conditions paired with a minimal loss of mass spectrometric detection sensitivity. A focus was put on the evaluation of the usability of different ...
DOI:
10.1016/j.chroma.2011.03.051

4. Multi-residue analysis of drugs of abuse in wastewater and surface water by solid-phase extraction and liquid chromatography–positive electrospray ionisation tandem mass spectrometry

Author:
David R. Baker; Barbara Kasprzyk-Hordern
Source:
Journal of chromatography 2011 v.1218 no.12 pp. 1620-1631
ISSN:
0021-9673
Subject:
anesthetics; antidepressants; benzodiazepines; caffeine; chromatography; cocaine; correlation; detection limit; environmental monitoring; humans; illicit drugs; ionization; metabolites; morphine; multiresidue analysis; particle size; rapid methods; river water; solid phase extraction; surface water; tandem mass spectrometry; urine; wastewater; wastewater treatment; United Kingdom
Abstract:
... A new-multi residue method was developed for the environmental monitoring of 65 stimulants, opiod and morphine derivatives, benzodiazepines, antidepressants, dissociative anaesthetics, drug precursors, human urine indicators and their metabolites in wastewater and surface water. The proposed analytical methodology offers rapid analysis for a large number of compounds, with low limits of quantifica ...
DOI:
10.1016/j.chroma.2011.01.060

5. A new method based on electrospray ionisation ion mobility spectrometry (ESI-IMS) for simultaneous determination of caffeine and theophylline

Author:
M.T. Jafari; B. Rezaei; M. Javaheri
Source:
Food chemistry 2011 v.126 no.4 pp. 1964-1970
ISSN:
0308-8146
Subject:
caffeine; foods; detection limit; theophylline; ions; green tea; ionization; high performance liquid chromatography; spectroscopy
Abstract:
... In this work for the first time, simultaneous analysis of caffeine and theophylline was done by ion mobility spectrometry (IMS) only, without a powerful separation technique (e.g., HPLC). Ion mobility spectrometry with low cost, inexpensive maintenance and very fast analysis makes an attractive technique for the simultaneous determination of the caffeine and theophylline in foodstuff samples and b ...
DOI:
10.1016/j.foodchem.2010.12.054
PubMed:
25213984

6. Development of a new multi-residue laser diode thermal desorption atmospheric pressure chemical ionization tandem mass spectrometry method for the detection and quantification of pesticides and pharmaceuticals in wastewater samples

Author:
Michel Boisvert; Paul B. Fayad; Sébastien Sauvé
Source:
Analytica chimica acta 2012 v.754 no. pp. 75-82
ISSN:
0003-2670
Subject:
anion exchange; atmospheric pressure; atrazine; caffeine; desorption; detection limit; drugs; estradiol; ionization; liquid chromatography; municipal wastewater; pH; solid phase extraction; sulfamethoxazole; tandem mass spectrometry; washing; wastewater treatment
Abstract:
... A new solid phase extraction (SPE) method coupled to a high throughput sample analysis technique was developed for the simultaneous determination of nine selected emerging contaminants in wastewater (atrazine, desethylatrazine, 17β-estradiol, ethynylestradiol, norethindrone, caffeine, carbamazepine, diclofenac and sulfamethoxazole). We specifically included pharmaceutical compounds from multiple t ...
DOI:
10.1016/j.aca.2012.09.046

7. High-sensitivity liquid chromatography–tandem mass spectrometry for the simultaneous determination of five drugs and their cytochrome P450-specific probe metabolites in human plasma

Author:
Kyung-Suk Oh; Su-Jin Park; Dhananjay D. Shinde; Jae-Gook Shin; Dong-Hyun Kim
Source:
Journal of chromatography 2012 v.895-896 no. pp. 56-64
ISSN:
1570-0232
Subject:
acetonitrile; caffeine; cytochrome P-450; drugs; formic acid; humans; ionization; liquid chromatography; metabolites; pharmacokinetics; propranolol; quantitative analysis; tandem mass spectrometry
Abstract:
... A sensitive liquid chromatography–tandem mass spectrometric (LC–MS/MS) method with electrospray ionization was developed for the simultaneous quantitation of five probe drugs and their metabolites in human plasma for assessing the in vivo activities of cytochrome P450 (CYP). CYP isoform specific substrates and their metabolites of CYP1A2 (caffeine), CYP2C9 (losartan), CYP2C19 (omeprazole), CYP2D6 ...
DOI:
10.1016/j.jchromb.2012.03.014

8. Measurement of iodide and caffeine content in cellulite reduction cosmetic products sold in the European market

Author:
Emilia Marchei; Daniela De Orsi; Carmine Guarino; Stefano Dorato; Roberta Pacifici; Simona Pichini
Source:
Analytical methods 2012 v.5 no.2 pp. 376-383
ISSN:
1759-9679
Subject:
acetaminophen; acetonitrile; caffeine; chemical species; cosmetics; dietary supplements; diodes; electrospray ionization mass spectrometry; ionization; reversed-phase liquid chromatography; supermarkets
Abstract:
... Two simple liquid chromatography (LC) separation methods coupled with ultraviolet diode array (UV-DAD) and an electrospray ionisation mass spectrometry (ESI-MS) detection have been developed for the determination of caffeine and iodide content in cellulite reduction cosmetic products. The presence of these substances in cosmetics available in the market should be taken into account in order not to ...
DOI:
10.1039/c2ay25761k

9. Ambient desorption/ionization mass spectrometry using a liquid sampling–atmospheric glow discharge (LS-APGD) ionization source

Author:
R. Kenneth Marcus; Carolyn Q. Burdette; Benjamin T. Manard; Lynn X. Zhang
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.25 pp. 8171-8184
ISSN:
1618-2642
Subject:
analgesics; caffeine; cigarettes; coffee beans; desorption; detection limit; electrodes; green tea; ionization; leaves; mass spectrometry; nickel; nitric acid; optics; paper; spectrometers
Abstract:
... A novel approach to ambient desorption/ionization mass spectrometry (ADI-MS) is described, based on a recently developed liquid sampling–atmospheric pressure glow discharge (LS-APGD) ionization source. The device is essentially unmodified relative to its implementation in elemental mass spectrometry, where the operational space is characterized by low operation power (<10 W) and low solution deliv ...
DOI:
10.1007/s00216-013-7216-3

10. Assessment of bitter taste of pharmaceuticals with multisensor system employing 3 way PLS regression

Author:
Alisa Rudnitskaya; Dmitry Kirsanov; Yulia Blinova; Evgeny Legin; Boris Seleznev; David Clapham; Robert S. Ives; Kenneth A. Saunders; Andrey Legin
Source:
Analytica chimica acta 2013 v.770 pp. 45-52
ISSN:
0003-2670
Subject:
acetaminophen; animal models; bitterness; caffeine; chlorhexidine; electronic tongue; humans; ingredients; ionization; pH; potassium nitrate; prediction; quinine; regression analysis; sensory evaluation; taste
Abstract:
... The application of the potentiometric multisensor system (electronic tongue, ET) for quantification of the bitter taste of structurally diverse active pharmaceutical ingredients (API) is reported. The measurements were performed using a set of bitter substances that had been assessed by a professional human sensory panel and the in vivo rat brief access taste aversion (BATA) model to produce bitte ...
DOI:
10.1016/j.aca.2013.02.006

11. Direct coupling of packed column supercritical fluid chromatography to continuous corona discharge ion mobility spectrometry

Author:
A. Rahmanian; H.S. Ghaziaskar; T. Khayamian
Source:
Journal of chromatography 2013 v.1272 no. pp. 126-131
ISSN:
0021-9673
Subject:
caffeine; carbon dioxide; detectors; electrodes; freezing; gases; ionization; medroxyprogesterone; methanol; spectroscopy; supercritical fluid chromatography; testosterone; theophylline
Abstract:
... In this study, packed column supercritical fluid chromatography (SFC) was directly coupled to a continuous corona discharge (CD) ion mobility spectrometer (IMS) with several modifications. The main advantage of the developed detector is its capability to introduce full column effluent up to 2000mLmin⁻¹ CO₂ gas directly into the IMS cell relative to 40mLmin⁻¹ CO₂ gas as a maximum tolerance, reporte ...
DOI:
10.1016/j.chroma.2012.11.063

12. Graphene matrix for signal enhancement in ambient plasma assisted laser desorption ionization mass spectrometry

Author:
Cuilan Chang; Xianjiang Li; Yu Bai; Gege Xu; Baosheng Feng; Yiping Liao; Huwei Liu
Source:
Talanta 2013 v.114 no. pp. 54-59
ISSN:
0039-9140
Subject:
absorption; caffeine; desorption; energy transfer; graphene; helium; ionization; irradiation; leaves; mass spectrometry; rapid methods; screening; tea; theanine
Abstract:
... In this work, the signal intensity of ambient plasma assisted laser desorption ionization mass spectrometry (PALDI-MS) was significantly increased with graphene as matrix. The graphene functions as a substrate to trap analytes, absorb energy from the visible laser irradiation and transfer energy to the analytes to facilitate the laser desorption process. The desorbed analytes are further ionized b ...
DOI:
10.1016/j.talanta.2013.04.007

13. High-performance liquid chromatographic analysis of biogenic amines in pharmaceutical products containing Citrus aurantium

Author:
Carine Viana; Gabriela M. Zemolin; Fernanda O. Lima; Leandro M. de Carvalho; Carla B. G. Bottoli; Renata Pereira Limberger
Source:
Food additives & contaminants 2013 v.30 no.4 pp. 634-642
ISSN:
1944-0057
Subject:
Caralluma; Cassia; Citrus aurantium; Cordia; Ephedra; Garcinia; Phaseolus vulgaris; caffeine; ephedrine; herbal medicines; hordenine; ionization; mass spectrometry; phytotherapy; raw materials; reversed-phase high performance liquid chromatography; tyramine; tyrosine
Abstract:
... A reverse-phase (RP)-HPLC method is reported for determining L-tyrosine, p-octopamine, synephrine, tyramine and hordenine as chemical markers of the species Citrus aurantium in raw material, dry extracts and phytotherapeutic herbal formulations. Using RP-HPLC with diode array detection (DAD) and gradient elution, the amines were determined in 12 different products from different Brazilian states l ...
DOI:
10.1080/19440049.2013.775606
PubMed:
23574611

14. Looking into individual coffee beans during the roasting process: direct micro-probe sampling on-line photo-ionisation mass spectrometric analysis of coffee roasting gases

Author:
Romy Hertz-Schünemann; Thorsten Streibel; Sven Ehlert; Ralf Zimmermann
Source:
Analytical and bioanalytical chemistry 2013 v.405 no.22 pp. 7083-7096
ISSN:
1618-2642
Subject:
Coffea arabica; Coffea canephora; caffeine; coffee beans; cultivars; flavor compounds; gases; ionization; lipids; mass spectrometry; multivariate analysis; phenol; roasting; temporal variation; volatile organic compounds
Abstract:
... A micro-probe (μ-probe) gas sampling device for on-line analysis of gases evolving in confined, small objects by single-photon ionisation time-of-flight mass spectrometry (SPI-TOFMS) was developed. The technique is applied for the first time in a feasibility study to record the formation of volatile and flavour compounds during the roasting process within (inside) or in the direct vicinity (outsid ...
DOI:
10.1007/s00216-013-7006-y

15. Monitoring tea fermentation/manufacturing by direct analysis in real time (DART) mass spectrometry

Author:
Karl Fraser; Geoff A. Lane; Don E. Otter; Scott J. Harrison; Siew-Young Quek; Yacine Hemar; Susanne Rasmussen
Source:
Food chemistry 2013 v.141 no.3 pp. 2060-2065
ISSN:
0308-8146
Subject:
Camellia sinensis; acids; caffeine; chemical composition; fermentation; ionization; ions; leaves; manufacturing; mass spectrometry; monitoring; processing stages; tea; volatile compounds
Abstract:
... Factors such as fermentation methods, geographical origin and season can affect the biochemical composition of tea leaves (Camellia sinensis L.). In this study, the biochemical composition of oolong tea during the manufacturing and fermentation process was studied using a non-targeted method utilising ambient ionisation with a direct analysis in real time (DART) ion source and mass spectrometry (M ...
DOI:
10.1016/j.foodchem.2013.05.054

16. Online Coupling of Capillary Electrophoresis with Direct Analysis in Real Time Mass Spectrometry

Author:
Chang Cuilan; Xu Gege; Bai Yu; Zhang Chengsen; Li Xianjiang; Li Min; Liu Yi; Liu Huwei
Source:
Analytical chemistry 2013 v.85 no.1 pp. 170-176
ISSN:
1520-6882
Subject:
caffeine; capillary zone electrophoresis; cleaning; correlation; detection limit; detergents; helium; ionization; mass spectrometry; micellar electrokinetic capillary chromatography; quantitative analysis; quinine; salts; sodium borate; white tea
Abstract:
... The online coupling of capillary electrophoresis with ambient direct analysis in real time mass spectrometry (DART-MS) was realized by a coaxial tip interface. The analytes eluted from capillary electrophoresis (CE) were directly ionized by the metastable helium flux produced by DART and transferred into MS for the detection, with which the online separation and simultaneous detection were achieve ...
DOI:
10.1021/ac303450v

17. Simultaneous quantification of caffeine and its three primary metabolites in rat plasma by liquid chromatography–tandem mass spectrometry

Author:
Eu Jin Choi; Soo Hyeon Bae; Jung Bae Park; Min Jo Kwon; Su Min Jang; Yu Fen Zheng; Young Sun Lee; Su-Jun Lee; Soo Kyung Bae
Source:
Food chemistry 2013 v.141 no.3 pp. 2735-2742
ISSN:
0308-8146
Subject:
acetaminophen; additives; beverages; caffeine; energy; ionization; mass spectrometry; metabolites; quantitative analysis; rats; spectrometers; theobromine; theophylline
Abstract:
... A rapid, sensitive, simple and accurate LC–MS/MS method for the simultaneous quantitation of caffeine, and its three primary metabolites, theobromine, paraxanthine, and theophylline, in rat plasma was developed and validated. Chromatographic separation was performed on an Agilent Poroshell 120 EC-C18 column using 1μg/mL acetaminophen as an internal standard. Each sample was run at 0.5mL/min for a ...
DOI:
10.1016/j.foodchem.2013.05.069

18. A rapid and sensitive LC–MS/MS assay for the determination of berbamine in rat plasma with application to preclinical pharmacokinetic study

Author:
Qingwang Liu; Junsong Wang; Lei Yang; Yuanwei Jia; Lingyi Kong
Source:
Journal of Chromatography B 2013 v.929 pp. 70-75
ISSN:
1570-0232
Subject:
Berberis; caffeine; formic acid; half life; intravenous injection; ionization; liquid chromatography; monitoring; pharmacokinetics; rats; tandem mass spectrometry
Abstract:
... Berbamine (BBM), a natural compound from Chinese herb Berberis amurensis, has recently received a great deal of attention due to its anti-leukemia activity. In this study, a rapid and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for the determination of BBM in rat plasma was developed for the first time. Caffeine was used as an internal standard. Chromatographic separ ...
DOI:
10.1016/j.jchromb.2013.04.007

19. Online measurement of volatile organic compounds released during roasting of cocoa beans

Author:
Jana Diab; Romy Hertz-Schünemann; Thorsten Streibel; Ralf Zimmermann
Source:
Food research international 2014 v.63 pp. 344-352
ISSN:
0963-9969
Subject:
analytical methods; caffeine; cocoa beans; fatty acids; ionization; methanethiol; monitoring; odor compounds; phenylacetaldehyde; photons; principal component analysis; pyrazines; roasting; spectrometers; theobromine; volatile organic compounds
Abstract:
... The gaseous species evolving during the roasting of cocoa beans were analyzed by a newly developed technique, a micro-probe–photo-ionization–time-of-flight mass spectrometer system. A lot of volatile roasting products and typical aroma compounds, such as methylbutanal, phenylacetaldehyde and pyrazines, could be online detected. The differences between the roast gas composition inside and outside t ...
DOI:
10.1016/j.foodres.2014.04.047

20. Sorption/desorption of non-hydrophobic and ionisable pharmaceutical and personal care products from reclaimed water onto/from a natural sediment

Author:
Virtudes Martínez-Hernández; Raffaella Meffe; Sonia Herrera; Elena Arranz; Irene de Bustamante
Source:
Science of the total environment 2014 v.472 pp. 273-281
ISSN:
0048-9697
Subject:
acetaminophen; caffeine; carbon; desorption; inorganic ions; ionization; organic matter; personal care products; rain; sandy loam soils; sediments; sulfamethoxazole
Abstract:
... In the present work, the sorption of pharmaceutical and personal care products (PPCPs) (acetaminophen, atenolol, carbamazepine, caffeine, naproxen and sulphamethoxazole) onto the natural organic matter (NOM) and the inorganic surfaces of a natural sandy loam sediment was quantified separately. The quantification was based on the PPCP charge, their degree of ionisation, their octanol–water partitio ...
DOI:
10.1016/j.scitotenv.2013.11.036

21. Water-soluble drug partitioning and adsorption in HEMA/MAA hydrogels

Author:
Thomas J. Dursch; Nicole O. Taylor; David E. Liu; Rong Y. Wu; John M. Prausnitz; Clayton J. Radke
Source:
Biomaterials 2014 v.35 no.2 pp. 620-629
ISSN:
0142-9612
Subject:
acetazolamide; adsorption; caffeine; carboxylic acids; composite polymers; confocal microscopy; cortisol; electrostatic interactions; fluorescein; hydrogels; ionization; moieties; pH; partition coefficients; salinity; solutes; spectroscopy; theophylline; water solubility
Abstract:
... Two-photon confocal microscopy and back extraction with UV/Vis-absorption spectrophotometry quantify equilibrium partition coefficients, k, for six prototypical drugs in five soft-contact-lens-material hydrogels over a range of water contents from 40 to 92%. Partition coefficients were obtained for acetazolamide, caffeine, hydrocortisone, Oregon Green 488, sodium fluorescein, and theophylline in 2 ...
DOI:
10.1016/j.biomaterials.2013.09.109

22. Corrigendum to “Sorption/desorption of non-hydrophobic and ionisable pharmaceutical and personal care products from reclaimed water onto/from a natural sediment” Sci Total Environ 472 (2014) 273–281

Author:
Virtudes Martínez-Hernández; Raffaella Meffe; Sonia Herrera; Elena Arranz; Irene de Bustamante
Source:
Science of the total environment 2015 v.505 pp. 1232-1233
ISSN:
0048-9697
Subject:
acetaminophen; caffeine; carbon; desorption; inorganic ions; ionization; organic matter; personal care products; rain; sandy loam soils; sediments; sulfamethoxazole
Abstract:
... In the present work, the sorption of pharmaceutical and personal care products (PPCPs) (acetaminophen, atenolol, carbamazepine, caffeine, naproxen and sulphamethoxazole) onto the natural organic matter (NOM) and the inorganic surfaces of a natural sandy loam sediment was quantified separately. The quantification was based on the PPCP charge, their degree of ionisation, their octanol-water partitio ...
DOI:
10.1016/j.scitotenv.2014.10.104

23. Drug cross-contamination of latent fingermarks during routine powder dusting detected by SALDI TOF MS

Author:
Latha Sundar; Frederick Rowell
Source:
Analytical methods 2015 v.7 no.9 pp. 3757-3763
ISSN:
1759-9679
Subject:
acetaminophen; aspirin; brushes; caffeine; cocaine; cross contamination; desorption; dusting; illicit drugs; ionization; magnetism; mass spectrometry; methadone; powders; squirrels; therapeutics
Abstract:
... The process of dusting powders over latent fingermarks was shown to transfer drug contact residues between adjacent marks. This was seen for marks contaminated after contact with two drugs of abuse (cocaine and methadone) and three therapeutic drugs (caffeine, aspirin and paracetamol). The powders used were a commercial black powder, and α-cyano-4-hydroxycinnamic acid both of which also act as ion ...
DOI:
10.1039/c5ay00598a

24. Microwave induced plasma desorption ionization (MIPDI) mass spectrometry for qualitative and quantitative analysis of preservatives in cosmetics

Author:
Zhongjun Zhao; Yixiang Duan
Source:
RSC advances 2015 v.5 no.51 pp. 40636-40646
ISSN:
2046-2069
Subject:
caffeine; desorption; detection limit; ionization; liquids; mass spectrometry; preservatives; quantitative analysis; screening; standard deviation; sunscreens
Abstract:
... Ambient ion sources for mass spectrometry have been frequently reported in the past 10 years. The most attractive features of these ion sources are that they are fast and an easy way to analyze various samples. The microwave induced plasma desorption ionization source, the MIPDI source, is one among them. In this study, the qualitative and quantitative behavior of the MIPDI source has been demonst ...
DOI:
10.1039/c5ra05137a

25. Miniature Flow-Through Low-Temperature Plasma Ionization Source for Ambient Ionization of Gases and Aerosols

Author:
Spencer Sandra E.; Santiago Brandon G.; Glish Gary L.
Source:
Analytical chemistry 2015 v.87 no.23 pp. 11887-11892
ISSN:
1520-6882
Subject:
aerosols; caffeine; cellulose; gases; ionization; ions; pyrolysis
Abstract:
... The design and operation of an inexpensive, miniature low-temperature plasma ion source is detailed. The miniature low-temperature plasma ion source is operated in a “flow-through” configuration, wherein the gaseous or aerosolized analyte, caffeine or pyrolyzed ethyl cellulose, in a carrier gas is used as the plasma gas. In this flow-through configuration, the sensitivity for the caffeine standard ...
DOI:
10.1021/acs.analchem.5b03447

26. Occurrence and distribution of phthalate esters and pharmaceuticals in Taiwan river sediments

Author:
Gordon C. C. Yang; Chih-Lung Wang; Yu-Han Chiu
Source:
Journal of soils and sediments 2015 v.15 no.1 pp. 198-210
ISSN:
1439-0108
Subject:
acetaminophen; animal husbandry; caffeine; ciprofloxacin; food industry; humans; ionization; lincomycin; liquid chromatography; monitoring; norfloxacin; personal care products; phthalates; rivers; sediments; sulfamethoxazole; sulfathiazole; tandem mass spectrometry; temporal variation; wet season; Taiwan
Abstract:
... PURPOSE: Phthalate esters (PAEs), pharmaceuticals, and personal care products (PPCPs) are used in industry, biosciences, agriculture, animal husbandry, food industry, and by humans. The aim of this study was to understand the occurrence, spatial distribution, and temporal variation of six phthalate esters and pharmaceuticals in river sediments in Taiwan. MATERIALS AND METHODS: Surface sediments we ...
DOI:
10.1007/s11368-014-1003-4

27. 3D printing of microfluidic devices for paper-assisted direct spray ionization mass spectrometry

Author:
Lucas Costa Duarte; Thays Colletes de Carvalho; Eulício Oliveira Lobo-Júnior; Patrícia V. Abdelnur; Boniek G. Vaz; Wendell K. T. Coltro
Source:
Analytical methods 2016 v.8 no.3 pp. 496-503
ISSN:
1759-9679
Subject:
caffeine; computer-aided design; formic acid; glucose; ionization; lysozyme; mass spectrometry; methanol; models; paper; qualitative analysis; styrene; thermoplastics; xylose
Abstract:
... This study describes the use of a 3D printer to fabricate microfluidic devices for direct spray ionization mass spectrometry (DS-MS) assisted by paper tips. The layout of the proposed devices was designed in a three-dimensional model through a computer-aided design system and printed by a fused deposition modeling method using a thermoplastic filament composed of acrylonitrile butadiene styrene de ...
DOI:
10.1039/c5ay03074a

28. Comparison of piracetam measured with HPLC-DAD, HPLC-ESI-MS, DIP-APCI-MS, and a newly developed and optimized DIP-ESI-MS

Author:
Claudia Lenzen; Gottfried A. Winterfeld; Oliver J. Schmitz
Source:
Analytical and bioanalytical chemistry 2016 v.408 no.15 pp. 4103-4110
ISSN:
1618-2642
Subject:
caffeine; camphor; detection limit; drugs; high performance liquid chromatography; ionization; polar compounds; quantitative analysis; solvents; spectrometers; temperature
Abstract:
... The direct inlet probe-electrospray ionization (DIP-ESI) presented here was based on the direct inlet probe-atmospheric pressure chemical ionization (DIP-APCI) developed by our group. It was coupled to an ion trap mass spectrometer (MS) for the detection of more polar compounds such as degradation products from pharmaceuticals. First, the position of the ESI tip, the gas and solvent flow rates, as ...
DOI:
10.1007/s00216-016-9499-7

29. Extraction of cocoa proanthocyanidins and their fractionation by sequential centrifugal partition chromatography and gel permeation chromatography

Author:
Vasilisa Pedan; Norbert Fischer; Sascha Rohn
Source:
Analytical and bioanalytical chemistry 2016 v.408 no.21 pp. 5905-5914
ISSN:
1618-2642
Subject:
acetone; caffeine; chemical analysis; cocoa beans; countercurrent chromatography; flavanols; flavonols; fractionation; gel chromatography; gels; hexane; high performance liquid chromatography; ionization; mass spectrometry; particle size; proanthocyanidins; secondary metabolites; solvents; theobromine
Abstract:
... Cocoa beans contain secondary metabolites ranging from simple alkaloids to complex polyphenols with most of them believed to possess significant health benefits. The increasing interest in these health effects has prompted the need to develop techniques for their extraction, fractionation, separation, and analysis. This work provides an update on analytical procedures with a focus on establishing ...
DOI:
10.1007/s00216-016-9705-7

30. Nanotip Ambient Ionization Mass Spectrometry

Author:
Zhou Zhenpeng; Lee Jae Kyoo; Kim Samuel C.; Zare Richard N.
Source:
Analytical chemistry 2016 v.88 no.10 pp. 5542-5548
ISSN:
1520-6882
Subject:
caffeine; detection limit; phenanthrenes; ionization; spectrometers; tungsten; mass spectrometry
Abstract:
... A method called nanotip ambient ionization mass spectrometry (NAIMS) is described, which applies high voltage between a tungsten nanotip and a metal plate to generate a plasma in which ionized analytes on the surface of the metal plate are directed to the inlet and analyzed by a mass spectrometer. The dependence of signal intensity is investigated as a function of the tip-to-plate distance, the ti ...
DOI:
10.1021/acs.analchem.6b01212

31. Organic micropollutants (OMPs) in natural waters: Oxidation by UV/H2O2 treatment and toxicity assessment

Author:
Oscar Rozas; Cristiane Vidal; Carolina Baeza; Wilson F. Jardim; Alfred Rossner; Héctor D. Mansilla
Source:
Water research 2016 v.98 pp. 109-118
ISSN:
0043-1354
Subject:
Daphnia magna; acute toxicity; aquatic environment; atrazine; caffeine; diclofenac; drinking; drinking water; drugs; forestry; humans; hydrogen peroxide; ionization; liquid chromatography; oxidation; personal care products; pollutants; river water; rivers; solid phase extraction; tandem mass spectrometry; toxic substances; toxicity testing; triclosan; wastewater; wastewater treatment; water purification; water quality; watersheds; Chile
Abstract:
... Organic micropollutants (OMPs) are ubiquitous in natural waters even in places where the human activity is limited. The presence of OMPs in natural water sources for human consumption encourages the evaluation of different water purification technologies to ensure water quality. In this study, the Biobío river (Chile) was selected since the watershed includes urban settlements and economic activit ...
DOI:
10.1016/j.watres.2016.03.069

32. Simultaneous identification and quantification of new psychoactive substances in blood by GC-APCI-QTOFMS coupled to nitrogen chemiluminescence detection without authentic reference standards

Author:
Ilkka Ojanperä; Samuel Mesihää; Ilpo Rasanen; Anna Pelander; Raimo A. Ketola
Source:
Analytical and bioanalytical chemistry 2016 v.408 no.13 pp. 3395-3400
ISSN:
1618-2642
Subject:
atmospheric pressure; blood; caffeine; chemiluminescence; forensic sciences; gas chromatography; instrumentation; ionization; mass spectrometry; nitrogen; psychotropic agents; quantitative analysis; reference standards; sheep; toxicology
Abstract:
... A novel platform is introduced for simultaneous identification and quantification of new psychoactive substances (NPS) in blood matrix, without the necessity of using authentic reference standards. The instrumentation consisted of gas chromatography (GC) coupled to nitrogen chemiluminescence detection (NCD) and atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (A ...
DOI:
10.1007/s00216-016-9461-8

33. Direct Analysis of Xanthine Stimulants in Archaeological Vessels by Laser Desorption Resonance Enhanced Multiphoton Ionization

Author:
Owens Shawn C.; Berenbeim Jacob A.; Ligare Marshall R.; Gulian Lisa E.; Siouri Faady M.; Boldissar Samuel; Tyson-Smith Stuart; Wilson Gregory; Ford Anabel; de Vries Mattanjah S.
Source:
Analytical chemistry 2017 v.89 no.5 pp. 2838-2843
ISSN:
1520-6882
Subject:
caffeine; desorption; detection limit; genetic markers; ionization; mass spectrometry; theobromine; theophylline; wavelengths; xanthine
Abstract:
... Resonance enhanced multiphoton ionization spectroscopy (REMPI) generates simultaneous vibronic spectroscopy and fragment free mass spectrometry to identify molecules within a complex matrix. We combined laser desorption with REMPI spectroscopy to study organic residues within pottery sherds from Maya vessels (600–900 CE) and Mississippian vessels (1100–1200 CE), successfully detecting three molecu ...
DOI:
10.1021/acs.analchem.6b03932

34. HPLC–DAD Method for Simultaneous Determination of Dipyrone (Metamizole) and Caffeine in Tablets and Identification of Major Degradation Product by Direct Infusion ESI–MS

Author:
James Cabral Vieira; Rubia Adriele Sversut; Isadora Theodoro Maciel; Aline Regina Hellmann Carollo; Marcos Serrou do Amaral; Nájla Mohamad Kassab
Source:
Chromatographia 2017 v.80 no.3 pp. 489-495
ISSN:
0009-5893
Subject:
acetonitrile; ambient temperature; analysis of variance; caffeine; confidence interval; detection limit; electrospray ionization mass spectrometry; high performance liquid chromatography; ionization; ions; models; pH; sodium; t-test
Abstract:
... A new chromatographic method for simultaneous determination of dipyrone (metamizole) and caffeine in tablets was developed and validated. Excellent resolution and quantification were obtained using a reverse-phase Acclaim® C18 column (250.0 × 4.6 mm; 5.0 μm particles) with acetonitrile/water (65:35 v/v) as mobile phase, adjusted to pH 7.5 using drops of water:triethylamine (99:1 v/v). The elution ...
DOI:
10.1007/s10337-017-3263-9

35. Quantification of cocaine and its adulterants (lidocaine and levamisole) using the Dragendorff reagent allied to paper spray ionization mass spectrometry

Author:
H. Santos; A. S. Lima; A. Mazega; E. Domingos; C. J. Thompson; A. O. Maldaner; P. R. Filgueiras; B. G. Vaz; W. Romão
Source:
Analytical methods 2017 v.9 no.24 pp. 3662-3668
ISSN:
1759-9679
Subject:
adulterants; caffeine; cocaine; color; flame ionization; forensic sciences; illicit drugs; ionization; levamisole; lidocaine; mass spectrometry; models; paper; paper chromatography; thin layer chromatography
Abstract:
... Thin layer chromatography is a simple, easy and cheap technique widely used in Brazilian forensic laboratories, being a screening test for the separation and identification of illicit drugs, such as cocaine and its adulterants. Herein, paper chromatography using the Dragendorff reagent (revealing agent) was employed to analyze cocaine and its adulterants (levamisole, lidocaine, caffeine, and phena ...
DOI:
10.1039/c7ay00588a

36. Quantification of xanthine- and uric acid-related compounds in urine using a “dilute-and-shoot” technique coupling ultra-high-performance liquid chromatography and high-resolution Orbitrap mass spectrometry

Author:
Adrian Rodriguez; Rosa Maria Gomila; Gabriel Martorell; Antonia Costa-Bauza; Felix Grases
Source:
Journal of chromatography 2017 v.1067 pp. 53-60
ISSN:
1570-0232
Subject:
caffeine; formic acid; hypoxanthine; ionization; mass spectrometry; metabolism; metabolites; nutrition assessment; quantitative analysis; renal calculi; solid phase extraction; spectrometers; theobromine; theophylline; ultra-performance liquid chromatography; uric acid; urine; xanthine
Abstract:
... Quantitative analysis of relevant metabolites in biofluids such as urine is often a tedious procedure, since it usually requires extraction, purification or preconcentration. For instance, in the analysis of methylxanthines in urine, a solid-phase extraction is often required. In the current work, a rapid and highly sensitive “dilute-and-shoot” method combining ultra-high-performance liquid chroma ...
DOI:
10.1016/j.jchromb.2017.09.047

37. Disk solid-phase extraction of multi-class pharmaceutical residues in tap water and hospital wastewater, prior to ultra-performance liquid chromatographic-tandem mass spectrometry (UPLC-MS/MS) analyses

Author:
Husam I. S. Kafeenah; Rozita Osman; N. K. A. Bakar
Source:
RSC advances 2018 v.8 no.70 pp. 40358-40368
ISSN:
2046-2069
Subject:
acetaminophen; anti-inflammatory agents; antihypertensive agents; bronchodilators; caffeine; detection limit; drug residues; hospitals; ionization; liquids; metformin; solid phase extraction; tandem mass spectrometry; tap water; wastewater; Malaysia
Abstract:
... In this work, a new clean-up and pre-concentration method based on disk solid-phase extraction (SPE) was developed to determine multi-class pharmaceutical residues covering a wide range of polarities (log Kₒw values from −0.5 to 5.1) in water systems, prior to ultra-performance liquid chromatographic-tandem mass spectrometry (UPLC-MS/MS) analyses. Electrospray ionisation in positive and negative m ...
DOI:
10.1039/c8ra06885b

38. Simultaneous LC–MS/MS determination of 40 legal and illegal psychoactive drugs in breast and bovine milk

Author:
Ester López-García; Nicola Mastroianni; Cristina Postigo; Yolanda Valcárcel; Silvia González-Alonso; Damia Barceló; Miren López de Alda
Source:
Food chemistry 2018 v.245 pp. 159-167
ISSN:
0308-8146
Subject:
breast milk; breasts; caffeine; food animals; ionization; liquid chromatography; metabolites; tandem mass spectrometry; tranquilizers; whole milk
Abstract:
... This work presents a fast, sensitive and reliable multi-residue methodology based on fat and protein precipitation and liquid chromatography-tandem mass spectrometry for the determination of common legal and illegal psychoactive drugs, and major metabolites, in breast milk. One-fourth of the 40 target analytes is investigated for the first time in this biological matrix. The method was validated i ...
DOI:
10.1016/j.foodchem.2017.10.005

39. A low-cost ambient desorption/ionization source for mass-spectrometry based on a dielectric barrier discharge

Author:
Jasmine S. Furter; Peter C. Hauser
Source:
Analytical methods 2018 v.10 no.23 pp. 2701-2711
ISSN:
1759-9679
Subject:
temperature; silica; caffeine; detection limit; quantitative analysis; calibration; drugs; ionization; nicotine; nitrogen; electrodes; helium; computer software; mass spectrometry; qualitative analysis; desorption
Abstract:
... An ambient ionization source for mass-spectrometry is described. It is based on a plasma generated in helium by a dielectric barrier discharge using two external electrodes arranged axially on a fused silica tube. The plasma is created with a sinusoidal voltage source having an amplitude of 7 kilovolts and a frequency of 27 kilohertz. The plasma cell as well as the excitation circuitry were design ...
DOI:
10.1039/c8ay00446c

40. Derivatization of Ions under the Conditions of Surface Assisted Laser Desorption/Ionization

Author:
A. A. Grechnikov; A. S. Borodkov; S. M. Nikiforov
Source:
Journal of analytical chemistry 2019 v.74 no.3 pp. 248-254
ISSN:
1061-9348
Subject:
atmospheric pressure; caffeine; derivatization; desorption; ionization; ions
Abstract:
... A method for the chemical modification (derivatization) of ions obtained by surface assisted laser desorption/ionization (SALDI) is proposed. Derivatization is based on the interaction of desorbed ions with alcohol molecules. The method is simple, does not affect the duration of analysis and ensures the improvement of the analytical characteristics of the SALDI method, when analysis is carried out ...
DOI:
10.1134/S1061934819030055

41. Fast analysis of caffeinated beverages using laser diode thermal desorption mass spectrometry (LDTD-MS/MS)

Author:
Wendy C. Andersen; Michael VanSickle; Joseph Storey; Virginia Sheldon; Jack Lohne; Sherri B. Turnipseed; Terri Thomas; Mark Madson
Source:
Food additives & contaminants 2019 v.36 no.11 pp. 1616-1625
ISSN:
1944-0057
Subject:
additives; atmospheric pressure; beverages; caffeine; desorption; detection limit; dietary supplements; diodes; high performance liquid chromatography; ingredients; ionization; liquids; methanol; rapid methods; sweeteners; tandem mass spectrometry; vitamins
Abstract:
... A rapid method for quantitative caffeine analysis in carbonated and non-carbonated beverages and liquid dietary supplement products was developed based on the direct sample introduction technique of laser diode thermal desorption atmospheric pressure chemical ionisation with tandem mass spectrometry (LDTD-MS/MS). Product samples were diluted with a mixture of methanol, water, and d₃-caffeine inter ...
DOI:
10.1080/19440049.2019.1658904

42. Fast screening and quantitative mass spectral imaging of thin-layer chromatography plates with flowing atmospheric-pressure afterglow high-resolution mass spectrometry

Author:
Christopher Kuhlmann; Maximilian Heide; Carsten Engelhard
Source:
Analytical and bioanalytical chemistry 2019 v.411 no.23 pp. 6213-6225
ISSN:
1618-2642
Subject:
acetaminophen; atmospheric pressure; caffeine; cortisone; desorption; detection limit; energy drinks; image analysis; ionization; isotope dilution technique; mass spectrometry; nicotine; particle size; screening; silica; stable isotopes; steroids; thin layer chromatography
Abstract:
... Thin-layer chromatography (TLC) was interfaced to high-resolution mass spectrometry (MS) using a flowing atmospheric-pressure afterglow (FAPA) ambient desorption/ionization source. The influence of different TLC stationary phases on the mass spectral signal response and mass spectral image quality in FAPA-MS was carefully investigated. Specifically, a mixture of selected analgesics (acetaminophen) ...
DOI:
10.1007/s00216-019-02013-8

43. A simple, fast method for the analysis of 20 contaminants of emerging concern in river water using large-volume direct injection liquid chromatography-tandem mass spectrometry

Author:
Josep Borrull; Agustí Colom; Josepa Fabregas; Eva Pocurull; Francesc Borrull
Source:
Analytical and bioanalytical chemistry 2019 v.411 no.8 pp. 1601-1610
ISSN:
1618-2642
Subject:
acetaminophen; caffeine; chemical species; detection limit; ibuprofen; ionization; liquid chromatography; personal care products; pesticides; pollutants; river water; rivers; spectrometers; standard deviation; tandem mass spectrometry; Spain
Abstract:
... A fast and sensitive method for the determination of a structurally and physico-chemically diverse group of contaminants of emerging concern (CEC) based on large-volume direct injection liquid chromatography-tandem mass spectrometry was developed. The method can be used to determine 20 CECs belonging to different pollutant families (pharmaceuticals, personal care products, and pesticides) in river ...
DOI:
10.1007/s00216-019-01602-x

44. Coupling of Laser Ablation and the Liquid Sampling-Atmospheric Pressure Glow Discharge Plasma for Simultaneous, Comprehensive Mapping: Elemental, Molecular, and Spatial Analysis

Author:
Htoo W. Paing; Tyler J. Bryant; C. Derrick Quarles; R. Kenneth Marcus
Source:
Analytical chemistry 2020 v.92 no.18 pp. 12622-12629
ISSN:
1520-6882
Subject:
analytical chemistry; analytical methods; breasts; caffeine; chickens; environmental assessment; glutamic acid; ionization; lead; lead nitrate; liquids; spatial data; thallium
Abstract:
... The spatial distributions of elemental and molecular species are vital pieces of information for a broad number of applications such as material development and bio/environmental analysis. There is currently no single analytical method that can simultaneously acquire elemental, molecular, and spatial information from a single sample. This paper presents the coupling of an NWR213 laser ablation (LA ...
DOI:
10.1021/acs.analchem.0c02677

45. Critical study of crop-derived biochars for soil amendment and pharmaceutical ecotoxicity reduction

Author:
Magda Caban; Agnieszka Folentarska; Hanna Lis; Paulina Kobylis; Aleksandra Bielicka-Giełdoń; Jolanta Kumirska; Wojciech Ciesielski; Piotr Stepnowski
Source:
Chemosphere 2020 v.248 pp. 125976
ISSN:
0045-6535
Subject:
adsorption; anions; anti-inflammatory agents; beta-adrenergic antagonists; biochar; caffeine; cation exchange capacity; cations; clay soils; crops; desorption; ecotoxicology; germination; ionization; metals; pH; sand; sandy soils; seeds; soil amendments; straw; sulfonamides; toxicity; washing; watercress
Abstract:
... In this study, biochars (BCs) produced from crops (straw and seeds) were tested for the applicability as additive to soils. The effect on pH, water capacity and cation exchange capacity of soil were tested. The ability for the sorption of pharmaceuticals (beta-blockers, anti-inflammatory drugs, sulfonamides, 17α-ethinylestradiol, carbamazepine, caffeine) using the batch sorption test was performed ...
DOI:
10.1016/j.chemosphere.2020.125976

46. Effective quantification of 11 tyrosine kinase inhibitors and caffeine in human plasma by validated LC-MS/MS method with potent phospholipids clean-up procedure. Application to therapeutic drug monitoring

Author:
Dora Koller; Viktoryia Vaitsekhovich; Cecile Mba; Juan L. Steegmann; Pablo Zubiaur; Francisco Abad-Santos; Aneta Wojnicz
Source:
Talanta 2020 v.208 pp. 120450
ISSN:
0039-9140
Subject:
acidity; adverse effects; caffeine; chemical species; cytochrome P-450; drugs; enzyme inhibitors; enzymes; humans; ionization; isotope labeling; isozymes; liquid chromatography; lymphocytic leukemia; metabolism; monitoring; myeloid leukemia; pH; patients; phospholipids; polycythemia; rheumatoid arthritis; stomach; tandem mass spectrometry; therapeutics; tyrosine
Abstract:
... Therapeutic drug monitoring (TDM) help to improve treatment efficacy and safety. Therefore, a simple and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous monitoring of 11 tyrosine kinase inhibitors (TKIs) in human plasma. TKIs included in the assay are used in the treatment of chronic myeloid leukemia (CML: imatinib, dasati ...
DOI:
10.1016/j.talanta.2019.120450

47. Analysis of Nonvolatile Molecules in Supercritical Carbon Dioxide Using Proton-Transfer-Reaction Ionization Time-of-Flight Mass Spectrometry

Author:
Toshinobu Hondo; Chihiro Ota; Yumi Miyake; Hiroshi Furutani; Michisato Toyoda
Source:
Analytical chemistry 2021 v.93 no.17 pp. 6589-6593
ISSN:
1520-6882
Subject:
analytical chemistry; caffeine; carbon dioxide; crystallization; electrospray ionization mass spectrometry; ionization; solutes; solvents; supercritical fluid extraction; temperature; volatile organic compounds
Abstract:
... Proton-transfer-reaction (PTR) mass spectrometry (MS) is capable of detecting trace-level volatile organic compounds (VOCs) in gaseous samples in real time. Therefore, PTR-MS has become a popular method in many different study areas. Most of the currently reported PTR-MS applications are designed to determine volatile compounds. However, the method might be applicable for nonvolatile organic compo ...
DOI:
10.1021/acs.analchem.1c00898

48. Quantitative detection of caffeine in beverages using flowing atmospheric-pressure afterglow (FAPA) ionization high-resolution mass spectrometry imaging and performance evaluation of different thin-layer chromatography plates as sample substrates

Author:
Maximilian Heide; Cristian C. Escobar-Carranza; Carsten Engelhard
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.15 pp. 4481-4495
ISSN:
1618-2642
Subject:
air; analytical chemistry; atmospheric pressure; black tea; caffeine; carbonated beverages; chemical species; desorption; glass; ionization; isotope labeling; liquids; mass spectrometry; quantitative analysis; silica; steel; thin layer chromatography
Abstract:
... Ambient desorption/ionization mass spectrometry (ADI-MS) is widely used as a rapid screening tool of samples in their native state without sample preparation. While analysis times are much less than 1 min per sample, one challenge of ADI-MS is the possibility to perform quantitative analysis of analytes in complex matrices. Typically, the goal is to probe a variety of different analytes in a compl ...
DOI:
10.1007/s00216-022-04045-z