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1. Femtoliter Gradient Elution System for Liquid Chromatography Utilizing Extended Nanofluidics

Author:
Shimizu, Hisashi; Toyoda, Kouto; Mawatari, Kazuma; Terabe, Shigeru; Kitamori, Takehiko
Source:
Analytical chemistry 2019 v.91 no.4 pp. 3009-3014
ISSN:
1520-6882
Subject:
high performance liquid chromatography,   etc   ; models; proteins; pumps;     Show all 4 Subjects
Abstract:
... A gradient system was developed for the separation of proteins on a femtoliter scale utilizing nanofluidic channels. In the history of chromatography, miniaturization of the separation column has been important for efficient separation and downsizing of instruments. Previously, our group developed a small and highly efficient chromatography system utilizing nanofluidic channels, although a flexibl ...
DOI:
10.1021/acs.analchem.8b05302

2. “Geländer” macrocycles: Synthesis, chirality and racemisation barriers

Author:
Lar, Claudia; Moisӑ, Mӑdӑlina Elena; Bogdan, Elena; Terec, Anamaria; Hӑdade, Niculina Daniela; Grosu, Ion; David, Luminiţa; Paizs, Csaba; Grosu, Ioana Georgeta
Source:
Tetrahedron letters 2019 v.60 no.4 pp. 335-340
ISSN:
0040-4039
Subject:
high performance liquid chromatography,   etc   ; cations; enantiomerism; enantiomers; organic compounds;     Show all 5 Subjects
Abstract:
... A new class of axially-chiral o,o′-bridged biphenyls containing etheroxime chains was obtained in good yields by the macrocyclisation reaction of o,o′-diformylbiphenyl dioxime with several ditosylated or dibrominated reagents. In all cases the enantiomers of the compounds were separated by HPLC using a chiral column (Chiralpack IC) and the stability of the enantiomers (barriers of racemisation) wa ...
DOI:
10.1016/j.tetlet.2018.12.047

3. Multiplicative On-Column Solute Focusing Using Spatially Dependent Temperature Programming for Capillary HPLC

Author:
Rerick, Michael T.; Groskreutz, Stephen R.; Weber, Stephen G.
Source:
Analytical chemistry 2019 v.91 no.4 pp. 2854-2860
ISSN:
1520-6882
Subject:
high performance liquid chromatography,   etc   ; enthalpy; forensic sciences; solutes; temperature;     Show all 5 Subjects
Abstract:
... The benefits of capillary liquid chromatography columns are truly realized when small, limited sample volumes require signal enhancement, but the available sample volume does not permit on-column focusing during injection onto a larger column. This dilemma is common when samples are naturally small or precious (such as in biological, forensic, art, and archeological investigations) and analyte con ...
DOI:
10.1021/acs.analchem.8b04826

4. Guidelines for tuning the macropore structure of monolithic columns for high‐performance liquid chromatography

Author:
Dores‐Sousa, José Luís; Fernández‐Pumarega, Alejandro; De Vos, Jelle; Lämmerhofer, Michael; Desmet, Gert; Eeltink, Sebastiaan
Source:
Journal of separation science 2019 v.42 no.2 pp. 522-533
ISSN:
1615-9306
Subject:
high performance liquid chromatography,   etc   ; guidelines; macropores; polymers; porosity;     Show all 5 Subjects
Abstract:
... The ability to control the external porosity and to tune the dimensions of the macropore size on multiple length scales provides the possibility of tailoring the monolithic support structure towards separation performance. This paper discusses the properties of conventional polymer–monolithic stationary phases and its limitations regarding the effects of morphology on kinetic performance. Furtherm ...
DOI:
10.1002/jssc.201801092

5. Vibrational and electronic spectroscopic detection and quantification of carminic acid in candies

Author:
Garrido, Carlos; Clavijo, Ernesto; Copaja, Sylvia; Gómez-Jeria, Juan; Campos-Vallette, Marcelo
Source:
Food chemistry 2019 v.283 pp. 164-169
ISSN:
0308-8146
Subject:
high performance liquid chromatography,   etc   ; Raman spectroscopy; aqueous solutions; candy; children; dyes; silver; spectral analysis;     Show all 8 Subjects
Abstract:
... Carminic acid (CA) contained in one kind of gummy candy was detected and quantified by using vibrational and electronic spectroscopy, respectively; the proposed methodology in solution is simple and rapid without sample pretreatment as usually used and reported. The identification of CA in candies was performed through the Raman and surface enhanced Raman scattering (SERS) spectra along with the e ...
DOI:
10.1016/j.foodchem.2018.12.123

6. A highly efficient microextraction technique based on deep eutectic solvent formed by choline chloride and p-cresol for simultaneous determination of lignans in sesame oils

Author:
Liu, Wei; Zhang, Kangdi; Yang, Guolong; Yu, Jingjing
Source:
Food chemistry 2019 v.281 pp. 140-146
ISSN:
0308-8146
Subject:
high performance liquid chromatography,   etc   ; calibration; choline; detection limit; lignans; liquid-phase microextraction; oils; p-cresol; solvents;     Show all 9 Subjects
Abstract:
... For simultaneous determination of lignans (i.e. sesamin, sesamolin and sesamol) in sesame oils, a highly efficient ultrasonic-assisted liquid–liquid microextraction (UALLME) technique was developed based on deep eutectic solvents (DESs) composed of choline chloride and p-cresol. Compared with the common polyols-based DESs (i.e. choline chloride-ethylene glycol), the phenolic DESs exhibited higher ...
DOI:
10.1016/j.foodchem.2018.12.088

7. Use of Basolite® F300 metal-organic framework for the dispersive solid-phase extraction of phthalic acid esters from water samples prior to LC-MS determination

Author:
González-Sálamo, Javier; González-Curbelo, Miguel Ángel; Hernández-Borges, Javier; Rodríguez-Delgado, Miguel Ángel
Source:
Talanta 2019 v.195 pp. 236-244
ISSN:
0039-9140
Subject:
high performance liquid chromatography,   etc   ; coordination polymers; mass spectrometry; pH; phthalates; solid phase extraction; solvents; sorbents; wastewater;     Show all 9 Subjects
Abstract:
... In the present work, a commercial metal-organic framework (Basolite® F300) has been applied for the first time as dispersive solid-phase extraction (dSPE) sorbent of eight phthalic acid esters (PAEs) (butyl benzyl phthalate, bis-2-n-butoxyethyl phthalate, bis-isopentyl phthalate, bis-n-pentyl phthalate, dicyclohexyl phthalate, di-(2-ethylhexyl) phthalate -DEHP-, di-n-octyl phthalate and diisononyl ...
DOI:
10.1016/j.talanta.2018.11.049

8. Liberation of lutein from spinach: Effects of heating time, microwave-reheating and liquefaction

Author:
Chung, Rosanna W.S.; Leanderson, Per; Gustafsson, Nelly; Jonasson, Lena
Source:
Food chemistry 2019 v.277 pp. 573-578
ISSN:
0308-8146
Subject:
high performance liquid chromatography,   etc   ; boiling; health promotion; heat; in vitro digestion; liquefaction; lutein; spinach;     Show all 8 Subjects
Abstract:
... Lutein, abundant in dark leafy vegetables, has been associated with several health promoting effects. Still, to what extent different preparation conditions and practices affect the liberation of lutein from food is not fully understood. Here, we compared a range of domestic methods under realistic conditions to prepare spinach, the most common lutein-rich vegetable. After preparations, samples we ...
DOI:
10.1016/j.foodchem.2018.11.023

9. Drug loading augmentation in polymeric nanoparticles using a coaxial turbulent jet mixer: Yong investigator perspective

Author:
Lim, Jong-Min; Cai, Truong; Mandaric, Stefan; Chopra, Sunandini; Han, Hyeonwoo; Jang, Seokkyu; Il Choi, Won; Langer, Robert; Farokhzad, Omid C.; Karnik, Rohit
Source:
Journal of colloid and interface science 2019 v.538 pp. 45-50
ISSN:
0021-9797
Subject:
high performance liquid chromatography,   etc   ; drugs; hexane; hydrophobicity; light scattering; mixing; nanomedicine; nanoparticles; turbulent flow;     Show all 9 Subjects
Abstract:
... In conventional ‘bulk’ nanoprecipitation, the capacity to load hydrophobic drugs into the polymeric nanoparticles (NPs) is limited to about 1%. The size distribution of the resulting NPs becomes polydisperse when higher precursor concentration is used to increase the drug loading. Hence, it should be possible to enhance the hydrophobic drug loading in polymeric NPs while maintaining the uniform NP ...
DOI:
10.1016/j.jcis.2018.11.029

10. Applicability and reliability of the glucose oxidase method in assessing α-amylase activity

Author:
Visvanathan, Rizliya; Jayathilake, Chathuni; Liyanage, Ruvini; Sivakanesan, Ramiah
Source:
Food chemistry 2019 v.275 pp. 265-272
ISSN:
0308-8146
Subject:
high performance liquid chromatography,   etc   ; alpha-amylase; enzyme activity; enzyme inhibition; glucose; glucose oxidase; maltose; monitoring;     Show all 8 Subjects
Abstract:
... Glucose oxidase (GOD) is an enzyme widely used in glucose monitoring systems owing to its high specificity towards glucose. However, in our previous work maltose was found to show significant interaction with GOD and based on this observation, a novel microplate-based method was developed to assess α-amylase inhibitory activity (GOD method). Concerns regarding the interaction of GOD with maltose h ...
DOI:
10.1016/j.foodchem.2018.09.114

11. Determination of bioactive nonvolatile ginger constituents in dietary supplements by a rapid and economic HPLC method: Analytical method development and single-laboratory validation

Author:
You, Hong; Ireland, Bailey; Moeszinger, Michael; Zhang, Haoshu; Snow, Laura; Krepich, Scott; Takagawa, Vivian
Source:
Talanta 2019 v.194 pp. 795-802
ISSN:
0039-9140
Subject:
high performance liquid chromatography,   etc   ; dietary supplements; ginger; ingredients; manufacturing; quality control; spectrometers; wavelengths;     Show all 8 Subjects
Abstract:
... Most of the validated methods for ginger-containing dietary supplements have long run time and low sensitivity and only analyze gingerols and shogaols. 6-Paradol and zingerone become popular in modern dietary supplement industry as bioactive ginger constituents. Therefore, we developed an efficient HPLC-UV/Vis method to analyze all above major constituents. Compared to 282/280 nm used by the curre ...
DOI:
10.1016/j.talanta.2018.10.075

12. Enhanced extraction and preconcentration of main target saponins from Panax notoginseng root using green and efficient formulated surfactant aqueous systems

Author:
Cui, Qi; Liu, Juzhao; Xu, Wenjing; Kang, Yu-Fei; Wang, Xinyu; Li, Yanyan; Fu, Yujie
Source:
Journal of cleaner production 2019 v.210 pp. 1507-1516
ISSN:
0959-6526
Subject:
high performance liquid chromatography,   etc   ; Panax notoginseng; bioactive compounds; ginsenosides; solvents; standard deviation; surfactants;     Show all 7 Subjects
Abstract:
... In this study, the formulated surfactant aqueous system composed of 2% (w/v) Triton X-114 and 0.03% (w/v) Gemini 16-5-16 coupled with ultrasonic-assisted technology has been selected as an effective method for the extraction and preconcentration of five main saponin compounds in Panax notoginseng root samples. Under the optimum parameters, the extraction yields of notoginsenoside R1, ginsenosides ...
DOI:
10.1016/j.jclepro.2018.11.142

13. Elevated levels of α-dicarbonyl compounds in the plasma of type II diabetics and their relevance with diabetic nephropathy

Author:
Wang, Xin-Jie; Ma, Sheng-Bo; Liu, Zhuo-Feng; Li, Heng; Gao, Wen-Yun
Source:
Journal of chromatography 2019 v.1106-1107 pp. 19-25
ISSN:
1570-0232
Subject:
high performance liquid chromatography,   etc   ; blood plasma; chronic diseases; data collection; diabetic nephropathy; diacetyl; patients; quantitative analysis;     Show all 8 Subjects
Abstract:
... The presence of α‑dicarbonyl compounds (α-DCs) in vivo has been associated with the development of complications of diabetes mellitus (DM) and also with other chronic diseases. Therefore, quantitative analysis of α-DCs in body fluids is crucial to understand their roles in the formation of these chronic diseases. We established in this study a practical HPLC-UV method to measure 3‑deoxyglucosone ( ...
DOI:
10.1016/j.jchromb.2018.12.027

14. An effective method based on medium‐pressure liquid chromatography and recycling high‐speed counter‐current chromatography for enrichment and separation of three minor components with similar polarity from Dracocephalum tanguticum

Author:
Yang, Xue; Wang, Nana; Shen, Cheng; Li, Hongmei; Zhao, Jingyang; Chen, Tao; Li, Yulin
Source:
Journal of separation science 2019 v.42 no.3 pp. 684-690
ISSN:
1615-9306
Subject:
high performance liquid chromatography,   etc   ; Dracocephalum; countercurrent chromatography; ethyl acetate; hexane; methanol; plant extracts; recycling; solvents;     Show all 9 Subjects
Abstract:
... The separation of minor compounds, especially those with similar polarities from a complex sample, remains challenging. In the proposed study, an effective method based on medium‐pressure liquid chromatography and recycling high‐speed counter‐current chromatography was developed for the enrichment and separation of three minor components from Dracocephalum tanguticum. The crude extract was directl ...
DOI:
10.1002/jssc.201800812

15. Highly sensitive fluorescent probe based on a novel phenothiazine dye for detection of thiophenols in real water samples and living cells

Author:
Hou, Peng; Wang, Jing; Fu, Shuang; Liu, Lei; Chen, Song
Source:
Analytical and bioanalytical chemistry 2019 v.411 no.4 pp. 935-942
ISSN:
1618-2642
Subject:
high performance liquid chromatography,   etc   ; fluorescence; fluorescent dyes; mass spectrometry; monitoring; phenothiazine; thiolysis;     Show all 7 Subjects
Abstract:
... Based on an excited-state intramolecular proton transfer (ESIPT) fluorophore, a novel fluorescent off-on probe for detection of thiophenols was designed and synthesized. This probe (λₑₓ = 401 nm, λₑₘ = 527 nm) displayed high specificity for sensing thiophenols over other biologically related species. Besides, this probe possessed capabilities of monitoring thiophenols with rapid response rate (3 m ...
DOI:
10.1007/s00216-018-1525-5

16. Influence of polyphenolic content on the in vitro allergenicity of old and new apple cultivars: A pilot study

Author:
Kschonsek, Josephine; Wiegand, Cornelia; Hipler, Uta-Christina; Böhm, Volker
Source:
Nutrition 2019 v.58 pp. 30-35
ISSN:
0899-9007
Subject:
high performance liquid chromatography,   etc   ; Betula; allergenicity; antigens; apples; cross reaction; cultivars; enzymatic browning; new variety; pollen;     Show all 10 Subjects
Abstract:
... More than 70% of birch pollen–allergic individuals are affected by a cross-allergy from apples. The aim of this study was to determine if an increased polyphenolic content of apples is inversely related to clinical allergic reactions in sufferers.The polyphenolic content of two old and two new apple cultivars was analyzed using high performance liquid chromatography. The in vitro concentration of ...
DOI:
10.1016/j.nut.2018.07.001

17. Development and validation of a method for simultaneous determination of trace levels of five macrocyclic lactones in cheese by HPLC-fluorescence after solid–liquid extraction with low temperature partitioning

Author:
de Souza Santos Cheibub, Ana Maria; Silva Bahiense de Lyra, Eduardo; Pereira Netto, Annibal Duarte
Source:
Food chemistry 2019 v.272 pp. 148-156
ISSN:
0308-8146
Subject:
high performance liquid chromatography,   etc   ; abamectin; cattle; cheeses; doramectin; eprinomectin; fluorescence; guidelines; ivermectin; moxidectin; solvents; temperature;     Show all 12 Subjects
Abstract:
... A highly sensitive analytical method was developed and validated, following international guidelines, for the determination of the residues of five macrocyclic lactones (MLs) (abamectin, doramectin, eprinomectin, ivermectin and moxidectin) in cheese. The extracts were concentrated by rotary-evaporation and derivatized; no clean-up was necessary. Despite matrix complexity, no significant matrix-eff ...
DOI:
10.1016/j.foodchem.2018.08.027

18. Evaluating the reliability of specific and global methods to assess the phenolic content of virgin olive oil: Do they drive to equivalent results?

Author:
Olmo-García, Lucía; Fernández-Fernández, Carmen; Hidalgo, Ana; Vílchez, Pedro; Fernández-Gutiérrez, Alberto; Marchal, Rosa; Carrasco-Pancorbo, Alegría
Source:
Journal of chromatography 2019 v.1585 pp. 56-69
ISSN:
0021-9673
Subject:
high performance liquid chromatography,   etc   ; acid hydrolysis; caffeic acid; colorimetry; extra-virgin olive oil; mass spectrometry; oleuropein;     Show all 7 Subjects
Abstract:
... Despite the huge number of different published methodologies, there is an open debate regarding which one is the most convenient analytical strategy for the determination of phenolic compounds from virgin olive oils. Diverse technical issues together with the disparity of criteria regarding results expression cause a lot of confusion. Herewith, a systematic comparison between specific (a powerful ...
DOI:
10.1016/j.chroma.2018.11.031

19. Simplex-centroid design and Derringer’s desirability function approach for simultaneous separation of phenolic compounds from Mimosa scabrella Bentham honeydew honeys by HPLC/DAD

Author:
Silva, Bibiana da; Valdomiro Gonzaga, Luciano; Fett, Roseane; Oliveira Costa, Ana Carolina
Source:
Journal of chromatography 2019 v.1585 pp. 182-191
ISSN:
0021-9673
Subject:
high performance liquid chromatography,   etc   ; Mimosa scabrella; formic acid; guidelines; honeydew honey; methanol; ovens; phenolic compounds; temperature;     Show all 9 Subjects
Abstract:
... Honeydew honeys have been under-evaluated about their major phenolic compounds, especially Mimosa scabrella Bentham (bracatinga) honeydew honey. In this work, a fast and robust chromatographic method was optimized for simultaneous separation and quantification by HPLC/DAD of 18 phenolic compounds detected in bracatinga honeydew honey. A simplex-centroid design, central composite rotatable design a ...
DOI:
10.1016/j.chroma.2018.11.072

20. Quantification of THC in Cannabis plants by fast-HPLC-DAD: A promising method for routine analyses

Author:
Burnier, Céline; Esseiva, Pierre; Roussel, Christophe
Source:
Talanta 2019 v.192 pp. 135-141
ISSN:
0039-9140
Subject:
high performance liquid chromatography,   etc   ; Cannabis; calibration; cannabidiol; forensic sciences; gas chromatography-mass spectrometry; plant extracts; tetrahydrocannabinol;     Show all 8 Subjects
Abstract:
... Nowadays, Gas Chromatography Mass Spectrometry (GC-MS) is mainly used in forensic sciences but suffers from limitations when the analysed compounds are thermally instable as it is the case for THC-A (Tetrahydrocannabinolic Acid) which is converted into Δ⁹-THC (Δ⁹-Tetrahydrocannabinol) that subsequently partially degrades. We propose herein a Fast High Pressure Liquid Chromatography (Fast-HPLC-DAD) ...
DOI:
10.1016/j.talanta.2018.09.012