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Kalisz O, Jaworska A, Studzińska S, Bocian S. Elimination of Toxic Solvents from Analytical Methods in Food Analysis: Caffeine Determination in Tea as an Example. Foods 2024; 13:1189. [PMID: 38672862 PMCID: PMC11048749 DOI: 10.3390/foods13081189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/10/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
This study presents an innovative method for caffeine determination in tea, employing ethanol as the sole organic solvent for both SPE sample preparation and chromatographic analysis. This approach aligns with green chemistry principles, as confirmed by a comparative study highlighting ethanol's safety and eco-friendliness compared to traditional solvents. The experiments validate ethanol's efficacy in caffeine extraction and chromatographic analysis, minimizing environmental impact and eliminating toxicity risks. Utilizing a reduced chromatography column enhances the method's efficiency and sustainability, resulting in a low limit of quantitation (0.125 μg/mL) and good reproducibility (RSD < 2.5%). Based on tea from the Polish market, the findings reveal the caffeine content (19.29-37.69 mg/g) and endorse ethanol's role in enhancing sustainable chemical analysis in food science.
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Affiliation(s)
| | | | | | - Szymon Bocian
- Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University, 7 Gagarin St., 87-100 Toruń, Poland; (O.K.); (A.J.); (S.S.)
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2
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Feilcke R, Bär V, Wendt C, Imming P. Antibacterial and Disinfecting Effects of Standardised Tea Extracts on More than 100 Clinical Isolates of Methicillin-Resistant Staphylococcus aureus. PLANTS (BASEL, SWITZERLAND) 2023; 12:3440. [PMID: 37836180 PMCID: PMC10575227 DOI: 10.3390/plants12193440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/25/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) infections are still a major problem in hospitals. The excellent safety profile, accessibility and anti-infective activity of tea extracts make them promising agents for the treatment of infected wounds. To investigate the possibility of sterilising MRSA-infected surfaces, including skin with tea extracts, we determined the MICs for different extracts from green and black tea (Camellia sinensis), including epigallocatechin gallate (EGCG), on a large number of clinical isolates of MRSA, selected to represent a high genetic diversity. The extracts were prepared to achieve the maximal extraction of EGCG from tea and were used as stable lyophilisate with a defined EGCG content. All extracts showed a complete inhibition of cell growth at a concentration of approx. 80 µg/mL of EGCG after a contact time of 24 h. Time-kill plots were recorded for the extract with the highest amount of EGCG. The reduction factor (RF) was 5 after a contact time of 240 min. EGCG and tea extracts showed an RF of 2 in methicillin-sensitive S. aureus. Extracts from green and black tea showed lower MICs than an aqueous solution with the same concentration of pure EGCG. To the best of our knowledge, we are the first to show a reduction of 99.999% of clinically isolated MRSA by green tea extract within 4 h.
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Affiliation(s)
- Ruth Feilcke
- Institut für Pharmazie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
| | - Volker Bär
- Institut für Pharmazie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
| | - Constanze Wendt
- Zentrum für Infektiologie, Universität Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
- Labor Dr. Limbach & Kollegen GbR, Medizinisches Versorgungszentrum, Im Breitspiel 15, 69126 Heidelberg, Germany
| | - Peter Imming
- Institut für Pharmazie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle, Germany
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3
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Duan Q, Xing Y, Guo K. Carboxylato-Pillar[6]arene-Based Fluorescent Indicator Displacement Assays for Caffeine Sensing. Front Chem 2022; 9:816069. [PMID: 34993181 PMCID: PMC8725816 DOI: 10.3389/fchem.2021.816069] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 12/02/2021] [Indexed: 11/18/2022] Open
Abstract
In the present work, we have developed a new indicator displacement system based on pillararene for anionic water-soluble carboxylato pillar [6] arene (WP6) and aromatic fluorescent dye safranine T (ST). A large fluorescence enhancement and colour change of ST were observed after complexation with electron-rich cavity in WP6 because of host-guest twisted intramolecular charge-transfer interactions. The constructed pillararene-indicator displacement system can be applied for caffeine selective detection in water.
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Affiliation(s)
- Qunpeng Duan
- School of Chemical and Printing-dyeing Engineering, Henan University of Engineering, Zhengzhou, China
| | - Yibo Xing
- School of Chemical and Printing-dyeing Engineering, Henan University of Engineering, Zhengzhou, China
| | - Kainan Guo
- School of Chemical and Printing-dyeing Engineering, Henan University of Engineering, Zhengzhou, China
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4
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Cao Y, Mei S, Huang C, Chen P. Estimates of Catechins Content in Green Tea: A Review Based on Meta-analysis. FOOD REVIEWS INTERNATIONAL 2021. [DOI: 10.1080/87559129.2021.2009509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Yanyan Cao
- Tea Research Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Sifan Mei
- Tea Research Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chuangsheng Huang
- Tea Research Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ping Chen
- Tea Research Institute, Zhejiang University, Hangzhou, Zhejiang, China
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5
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Drakula S, Mustač NČ, Novotni D, Voučko B, Krpan M, Hruškar M, Ćurić D. Optimization and Validation of a HS-SPME/GC–MS Method for the Analysis of Gluten-Free Bread Volatile Flavor Compounds. FOOD ANAL METHOD 2021. [DOI: 10.1007/s12161-021-02076-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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6
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Kataoka H. In-tube solid-phase microextraction: Current trends and future perspectives. J Chromatogr A 2020; 1636:461787. [PMID: 33359971 DOI: 10.1016/j.chroma.2020.461787] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 12/02/2020] [Accepted: 12/04/2020] [Indexed: 01/01/2023]
Abstract
In-tube solid-phase microextraction (IT-SPME) was developed about 24 years ago as an effective sample preparation technique using an open tubular capillary column as an extraction device. IT-SPME is useful for micro-concentration, automated sample cleanup, and rapid online analysis, and can be used to determine the analytes in complex matrices simple sample processing methods such as direct sample injection or filtration. IT-SPME is usually performed in combination with high-performance liquid chromatography using an online column switching technology, in which the entire process from sample preparation to separation to data analysis is automated using the autosampler. Furthermore, IT-SPME minimizes the use of harmful organic solvents and is simple and labor-saving, making it a sustainable and environmentally friendly green analytical technique. Various operating systems and new sorbent materials have been developed to improve its extraction efficiency by, for example, enhancing its sorption capacity and selectivity. In addition, IT-SPME methods have been widely applied in environmental analysis, food analysis and bioanalysis. This review describes the present state of IT-SPME technology and summarizes its current trends and future perspectives, including method development and strategies to improve extraction efficiency.
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Affiliation(s)
- Hiroyuki Kataoka
- School of Pharmacy, Shujitsu University, Nishigawara, Okayama 703-8516, Japan.
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7
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Quantitative Analysis and Discrimination of Partially Fermented Teas from Different Origins Using Visible/Near-Infrared Spectroscopy Coupled with Chemometrics. SENSORS 2020; 20:s20195451. [PMID: 32977413 PMCID: PMC7582835 DOI: 10.3390/s20195451] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/16/2020] [Accepted: 09/20/2020] [Indexed: 12/24/2022]
Abstract
Partially fermented tea such as oolong tea is a popular drink worldwide. Preventing fraud in partially fermented tea has become imperative to protect producers and consumers from possible economic losses. Visible/near-infrared (VIS/NIR) spectroscopy integrated with stepwise multiple linear regression (SMLR) and support vector machine (SVM) methods were used for origin discrimination of partially fermented tea from Vietnam, China, and different production areas in Taiwan using the full visible NIR wavelength range (400-2498 nm). The SMLR and SVM models achieved satisfactory results. Models using data from chemical constituents' specific wavelength ranges exhibited a high correlation with the spectra of teas, and the SMLR analyses improved discrimination of the types and origins when performing SVM analyses. The SVM models' identification accuracies regarding different production areas in Taiwan were effectively enhanced using a combination of the data within specific wavelength ranges of several constituents. The accuracy rates were 100% for the discrimination of types, origins, and production areas of tea in the calibration and prediction sets using the optimal SVM models integrated with the specific wavelength ranges of the constituents in tea. NIR could be an effective tool for rapid, nondestructive, and accurate inspection of types, origins, and production areas of teas.
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8
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Mejía-Carmona K, Lanças FM. Modified graphene-silica as a sorbent for in-tube solid-phase microextraction coupled to liquid chromatography-tandem mass spectrometry. Determination of xanthines in coffee beverages. J Chromatogr A 2020; 1621:461089. [PMID: 32362360 DOI: 10.1016/j.chroma.2020.461089] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/10/2020] [Accepted: 03/29/2020] [Indexed: 02/03/2023]
Abstract
Given the increasing need for analyzing natural or contaminating compounds in complex food matrices in a simple and automated way, coupling miniaturized sample preparation techniques with chromatographic systems have become a growing field of research. In this regard, given the low extraction efficiency of conventional sorbent phases, the development of materials with enhanced extraction capabilities is of particular interest. Here we present several synthesized graphene-based materials supported on aminopropyl silica as sorbents for the extraction of xanthines. The synthesized materials were characterized by infrared spectroscopy and scanning electron microscopy. Aminopropyl silica coated with graphene oxide and functionalized with octadecylsilane/end-capped (SiGOC18ecap) showed the best performance for xanthines extraction. Hence, this material was employed as an in-tube solid phase microextraction (in-tube SPME) device coupled online with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and applied for the analysis of xanthines in roasted coffee samples. Extraction parameters and detection conditions were optimized. The method showed low limits of quantification (0.3-1.0 µg L-1), precision as relative standard deviation (RSD) values lower than 10%, recoveries between 73 and 109%, and pre-concentration factors from 5.6 to 7.2. Caffeine was determined in all ground roasted and instant coffee samples, in a wide range (0.9 to 36.8 mg g-1), and small amounts of theobromine and theophylline were also detected in some samples. This work demonstrated that functionalized graphene-based materials represent a promising new sorbent class for in-tube SPME, showing improved extraction capacity. The method was efficient, simple, and fast for the analysis of xanthines, demonstrating an excellent potential to be applied in other matrices.
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Affiliation(s)
- Karen Mejía-Carmona
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos SP, Brazil
| | - Fernando M Lanças
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos SP, Brazil.
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9
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On-line in-tube solid phase microextraction coupled to capillary liquid chromatography-diode array detection for the analysis of caffeine and its metabolites in small amounts of biological samples. J Pharm Biomed Anal 2020; 178:112914. [DOI: 10.1016/j.jpba.2019.112914] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 10/04/2019] [Accepted: 10/05/2019] [Indexed: 11/18/2022]
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10
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Current Trends in Fully Automated On-Line Analytical Techniques for Beverage Analysis. BEVERAGES 2019. [DOI: 10.3390/beverages5010013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The determination of target analytes in complex matrices such as beverages requires a series of analytical steps to obtain a reliable analysis. This critical review presents the current trends in sample preparation techniques based on solid phase extraction miniaturization, automation and on-line coupling. Techniques discussed include solid-phase extraction (SPE), solid-phase microextraction (SPME), in-tube solid-phase microextraction (in-tube SPME) and turbulent-flow chromatography (TFC). Advantages and limitations, as well as several of their main applications in beverage samples are discussed. Finally, fully automated on-line systems that involve extraction, chromatographic separation, and tandem mass spectrometry in one-step are introduced and critically reviewed.
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11
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Asiabi H, Yamini Y, Shamsayei M. Development of electrochemically controlled packed-in-tube solid phase microextraction method for sensitive analysis of acidic drugs in biological samples. Talanta 2018; 185:80-88. [DOI: 10.1016/j.talanta.2018.03.058] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/20/2018] [Accepted: 03/20/2018] [Indexed: 11/30/2022]
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12
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Dey N, Maji B, Bhattacharya S. A Versatile Probe for Caffeine Detection in Real-Life Samples via Excitation-Triggered Alteration in the Sensing Behavior of Fluorescent Organic Nanoaggregates. Anal Chem 2017; 90:821-829. [DOI: 10.1021/acs.analchem.7b03520] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Nilanjan Dey
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Basudeb Maji
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Santanu Bhattacharya
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
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13
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Piri-Moghadam H, Alam MN, Pawliszyn J. Review of geometries and coating materials in solid phase microextraction: Opportunities, limitations, and future perspectives. Anal Chim Acta 2017; 984:42-65. [PMID: 28843569 DOI: 10.1016/j.aca.2017.05.035] [Citation(s) in RCA: 208] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 05/23/2017] [Accepted: 05/25/2017] [Indexed: 12/18/2022]
Abstract
The development of new support and geometries of solid phase microextraction (SPME), including metal fiber assemblies, coated-tip, and thin film microextraction (TFME) (i.e. self-supported, fabric and blade supported), as well as their effects on diffusion and extraction rate of analytes were discussed in the current review. Application of main techniques widely used for preparation of a variety of coating materials of SPME, including sol-gel technique, electrochemical and electrospinning methods as well as the available commercial coatings, were presented. Advantages and limitations of each technique from several aspects, such as range of application, biocompatibility, availability in different geometrical configurations, method of preparation, incorporation of various materials to tune the coating properties, and thermal and physical stability, were also investigated. Future perspectives of each technique to improve the efficiency and stability of the coatings were also summarized. Some interesting materials including ionic liquids (ILs), metal organic frameworks (MOFs) and particle loaded coatings were briefly presented.
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Affiliation(s)
- Hamed Piri-Moghadam
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Md Nazmul Alam
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Janusz Pawliszyn
- Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.
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14
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Serra-Mora P, Moliner-Martínez Y, Molins-Legua C, Herráez-Hernández R, Verdú-Andrés J, Campíns-Falcó P. Trends in Online Intube Solid Phase Microextraction. COMPREHENSIVE ANALYTICAL CHEMISTRY 2017. [DOI: 10.1016/bs.coac.2017.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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15
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Moliner-Martinez Y, Herráez-Hernández R, Verdú-Andrés J, Molins-Legua C, Campíns-Falcó P. Recent advances of in-tube solid-phase microextraction. Trends Analyt Chem 2015. [DOI: 10.1016/j.trac.2015.02.020] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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16
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Recent Developments and Applications of Solid Phase Microextraction (SPME) in Food and Environmental Analysis—A Review. CHROMATOGRAPHY 2015. [DOI: 10.3390/chromatography2030293] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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17
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Molecularly imprinted sol-gel nanofibers based solid phase microextraction coupled on-line with high performance liquid chromatography for selective determination of acesulfame. Talanta 2015; 134:340-347. [DOI: 10.1016/j.talanta.2014.11.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 09/27/2014] [Accepted: 11/06/2014] [Indexed: 11/21/2022]
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18
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GC–MS Characterization of Volatile Compounds in Habanero Pepper (Capsicum chinense Jacq.) by Optimization of Headspace Solid-Phase Microextraction Conditions. FOOD ANAL METHOD 2014. [DOI: 10.1007/s12161-014-9980-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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19
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Bagheri H, Piri-Moghadam H. Electroentrapment of Polyaniline in [3-(2,3-Epoxypropoxy)propyl]trimethoxysilane-Derived Xerogel: A Facile Methodology Towards Molecularly Imprinted Xerogels. Chromatographia 2014. [DOI: 10.1007/s10337-014-2703-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Bagheri H, Bayat P, Piri-Moghadam H. Grafting the sol–gel based sorbents by diazonium salts: A novel approach toward unbreakable capillary microextraction. J Chromatogr A 2013; 1318:58-64. [DOI: 10.1016/j.chroma.2013.10.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 10/06/2013] [Accepted: 10/09/2013] [Indexed: 10/26/2022]
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21
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Shiue CC, Lin SY, Liu CY. Chemically Bonded Fullerene C60Capillary Column for the Electrophoretic Separation of Plant Phenols. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.200100150] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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Development of coatings for automated 96-blade solid phase microextraction-liquid chromatography–tandem mass spectrometry system, capable of extracting a wide polarity range of analytes from biological fluids. J Chromatogr A 2012; 1261:91-8. [DOI: 10.1016/j.chroma.2012.07.012] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 06/30/2012] [Accepted: 07/05/2012] [Indexed: 11/22/2022]
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23
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Role of precursors and coating polymers in sol–gel chemistry toward enhanced selectivity and efficiency in solid phase microextraction. Anal Chim Acta 2012; 742:45-53. [DOI: 10.1016/j.aca.2012.02.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 02/08/2012] [Accepted: 02/11/2012] [Indexed: 10/28/2022]
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24
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Talik P, Krzek J, Ekiert RJ. Analytical Techniques Used for Determination of Methylxanthines and their Analogues—Recent Advances. SEPARATION AND PURIFICATION REVIEWS 2012. [DOI: 10.1080/15422119.2011.569047] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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25
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Bedner M, Duewer DL. Dynamic Calibration Approach for Determining Catechins and Gallic Acid in Green Tea Using LC–ESI/MS. Anal Chem 2011; 83:6169-76. [DOI: 10.1021/ac200372d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mary Bedner
- National Institute of Standards and Technology, Analytical Chemistry Division Gaithersburg, Maryland 20899, United States
| | - David L. Duewer
- National Institute of Standards and Technology, Analytical Chemistry Division Gaithersburg, Maryland 20899, United States
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26
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Bagheri H, Piri-Moghadam H, Es’haghi A. An unbreakable on-line approach towards sol–gel capillary microextraction. J Chromatogr A 2011; 1218:3952-7. [DOI: 10.1016/j.chroma.2011.04.059] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 04/17/2011] [Accepted: 04/22/2011] [Indexed: 11/16/2022]
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27
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Yu QW, Ma Q, Feng YQ. Temperature-response polymer coating for in-tube solid-phase microextraction coupled to high-performance liquid chromatography. Talanta 2011; 84:1019-25. [DOI: 10.1016/j.talanta.2011.03.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 02/27/2011] [Accepted: 03/01/2011] [Indexed: 10/18/2022]
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28
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Khan I, Sangwan PL, Abdullah ST, Gupta BD, Dhar JK, Manickavasagar R, Koul S. Ten marker compounds-based comparative study of green tea and guava leaf by HPTLC densitometry methods: Antioxidant activity profiling. J Sep Sci 2011; 34:749-60. [DOI: 10.1002/jssc.201000718] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 01/09/2011] [Accepted: 01/09/2011] [Indexed: 12/11/2022]
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29
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Tharayil N, Triebwasser DJ. Elucidation of a diurnal pattern of catechin exudation by Centaurea stoebe. J Chem Ecol 2010; 36:200-4. [PMID: 20155499 DOI: 10.1007/s10886-010-9749-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 01/12/2010] [Accepted: 01/15/2010] [Indexed: 11/29/2022]
Abstract
The exudation of secondary metabolites at phytotoxic concentrations has been proposed as a mechanism of invasion for some exotic plant species. Catechin is a natural flavanoid implicated in the potential allelopathic interactions of Centaurea stoebe. However, recent studies have shown that catechin is highly unstable and not likely to accumulate in growing medium at phytotoxic concentrations. All previous studies that investigated the allelopathic potential of catechin assumed a continuous exudation of this compound by C. stoebe. Contrary to this, but similar to many other plant secondary metabolites, we hypothesized that catechin exudation may exhibit a pulsed pattern that could facilitate its transient accumulation. Further, we aimed at optimizing a more sensitive detection technique. We tested the hypothesis by quantifying the diurnal pattern of catechin release by C. stoebe in a hydroponic system. Using sample processing, based on a solid phase extraction technique, and more sensitive fluorescent detection parameters, we were able to quantify catechin in the picomolar range from the growing medium. Catechin exudation exhibited a possible diurnal rhythm with respect to light intensity, with the highest concentration at 6 h after exposure to sunlight. Catechin also was found to undergo a degradation reaction resulting in a transient abundance of pyrocatechol in our system.
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Affiliation(s)
- Nishanth Tharayil
- Entomology Soils & Plant Sciences, Clemson University, Clemson, SC, USA.
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30
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Solid-Phase Microextraction (SPME) Techniques for Quality Characterization of Food Products: A Review. FOOD BIOPROCESS TECH 2010. [DOI: 10.1007/s11947-009-0299-3] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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31
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Kataoka H, Ishizaki A, Nonaka Y, Saito K. Developments and applications of capillary microextraction techniques: A review. Anal Chim Acta 2009; 655:8-29. [DOI: 10.1016/j.aca.2009.09.032] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 09/19/2009] [Accepted: 09/22/2009] [Indexed: 11/30/2022]
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32
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Bai F, Iacono LC, Johnston B, Stewart CF. Determination of Gefitinib in Plasma by Liquid Chromatography with a C12 Column and Electrospray Tandem Mass Spectrometry Detection. J LIQ CHROMATOGR R T 2009. [DOI: 10.1081/jlc-200029312] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Feng Bai
- a Department of Pharmaceutical Sciences , St. Jude Children's Research Hospital , 332 N. Lauderdale, Memphis , Tennessee , 38105 , USA
| | - Lisa C. Iacono
- a Department of Pharmaceutical Sciences , St. Jude Children's Research Hospital , 332 N. Lauderdale, Memphis , Tennessee , 38105 , USA
| | - Brad Johnston
- a Department of Pharmaceutical Sciences , St. Jude Children's Research Hospital , 332 N. Lauderdale, Memphis , Tennessee , 38105 , USA
| | - Clinton F. Stewart
- a Department of Pharmaceutical Sciences , St. Jude Children's Research Hospital , 332 N. Lauderdale, Memphis , Tennessee , 38105 , USA
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33
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Canuti V, Conversano M, Calzi ML, Heymann H, Matthews MA, Ebeler SE. Headspace solid-phase microextraction-gas chromatography-mass spectrometry for profiling free volatile compounds in Cabernet Sauvignon grapes and wines. J Chromatogr A 2009; 1216:3012-22. [PMID: 19233370 DOI: 10.1016/j.chroma.2009.01.104] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2008] [Revised: 01/27/2009] [Accepted: 01/29/2009] [Indexed: 10/21/2022]
Abstract
The complex aroma of wine is derived from many sources, with grape-derived components being responsible for the varietal character. The ability to monitor grape aroma compounds would allow for better understanding of how vineyard practices and winemaking processes influence the final volatile composition of the wine. Here, we describe a procedure using GC-MS combined with headspace solid-phase microextraction (HS-SPME) for profiling the free volatile compounds in Cabernet Sauvignon grapes. Different sample preparation (SPME fiber type, extraction time, extraction temperature and dilution solvent) and GC-MS conditions were evaluated to optimize the method. For the final method, grape skins were homogenized with water and 8 ml of sample were placed in a 20 ml headspace vial with addition of NaCl; a polydimethylsiloxane SPME fiber was used for extraction at 40 degrees C for 30 min with continuous stirring. Using this method, 27 flavor compounds were monitored and used to profile the free volatile components in Cabernet Sauvignon grapes at different maturity levels. Ten compounds from the grapes, including 2-phenylethanol and beta-damascenone, were also identified in the corresponding wines. Using this procedure it is possible to follow selected volatiles through the winemaking process.
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Affiliation(s)
- Valentina Canuti
- Dipartimento di Biotecnologie Agrarie, Sezione di Tecnologie Alimentari, Firenze, Italy
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34
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Dou J, Lee VSY, Tzen JTC, Lee MR. Rapid identification of acylated flavonol tetraglycosides in oolong teas using HPLC-MSn. PHYTOCHEMICAL ANALYSIS : PCA 2008; 19:251-257. [PMID: 17994533 DOI: 10.1002/pca.1044] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A method was developed to separate and identify acylated flavonol tetraglycosides (AFTGs) by combining isocratic HPLC with electrospray ionisation tandem mass spectrometry. Better separation was obtained for oolong tea infusion using a manually packed Sephadex LH-20 mini-column than with an ACCUBOND ODS solid-phase column. Seven unknown and one known AFTGs were found in oolong teas prepared by various semi-fermentation processes and their structures were identified by mass spectrometry. According to the analyses of diverse oolong teas including Dongding Oolong, Tieguanyin, Wuyi Oolong, Fenghuang Oolong, Gaoshan Shibi, Laocong Shuixian and Baihao Oolong, AFTGs seemed to be universally present, and each oolong tea could be classified into one of three groups (Dongding Oolong, Tieguanyin and Wuyi Oolong) on the basis of its AFTGs profile. The results suggest that the developed method is rapid and sensitive for identifying natural compounds.
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Affiliation(s)
- Jianpeng Dou
- Department of Chemistry, National Chung-Hsing University, Taichung, Taiwan 40227, Republic of China
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35
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Wardencki W, Curyło J, Namieśnik J. Trends in solventless sample preparation techniques for environmental analysis. ACTA ACUST UNITED AC 2007; 70:275-88. [DOI: 10.1016/j.jbbm.2006.07.004] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Accepted: 07/31/2006] [Indexed: 10/24/2022]
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36
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Tzanavaras PD, Themelis DG. Development and validation of a high-throughput high-performance liquid chromatographic assay for the determination of caffeine in food samples using a monolithic column. Anal Chim Acta 2007; 581:89-94. [DOI: 10.1016/j.aca.2006.07.081] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Revised: 07/29/2006] [Accepted: 07/31/2006] [Indexed: 10/24/2022]
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37
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38
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Masukawa Y, Matsui Y, Shimizu N, Kondou N, Endou H, Kuzukawa M, Hase T. Determination of green tea catechins in human plasma using liquid chromatography-electrospray ionization mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 834:26-34. [PMID: 16513433 DOI: 10.1016/j.jchromb.2006.02.008] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Revised: 01/25/2006] [Accepted: 02/04/2006] [Indexed: 10/25/2022]
Abstract
A method for the sensitive and specific determination of eight green tea catechins, consisting of catechin (C), epicatechin (EC), gallocatechin (GC), epigallocatechin (EGC), catechin-3-gallate (CG), epicatechin-3-gallate (ECG), gallocatechin-3-gallate (GCG) and epigallocatechin-3-gallate (EGCG), in human plasma was established. For optimization of conditions for LC-ESIMS, the separation of the eight catechins was achieved chromatographically using Inertsil ODS-2 column combined with a gradient elution system of 0.1M aqueous acetic acid and 0.1M acetic acid in acetonitrile. Detection using a mass spectrometer was performed with selected ion monitoring at m/z=289 for E and EC, 305 for GC and EGC, 441 for CG and ECG, and 457 for GCG and EGCG under negative ESI. A preparative procedure, consisting of the addition of perchloric acid and acetonitrile to the plasma for deproteinizing and the subsequent addition of potassium carbonate solution to remove excess acid, was developed. In six different plasma with the eight catechins spiked at two different concentrations, the average recoveries were in the range between 72.7 and 84.1%, which resulted from the matrix effect and preparative loss, with coefficients of variance being 8.2-19.8% among individuals. The levels of the catechins in prepared plasma solutions that were kept at 5 degrees C within 24h were stable, which allows us to simply analyze many prepared plasma solutions using an autosampler overnight. When using this method to analyze the eight catechins in human plasma after oral ingestion of a commercial green tea beverage, we detected all the catechins absorbed into human blood for the first time. This also suggested that extremely small amounts of the eight catechins orally ingested may be absorbed based on each absorptive property for the catechins. The method should enable pharmacokinetic studies of green tea catechins in humans.
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Affiliation(s)
- Yoshinori Masukawa
- Tochigi Research Laboratories, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, 321-3497, Japan.
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39
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Wei F, Fan Y, Zhang M, Feng YQ. Poly(methacrylic acid-ethylene glycol dimethacrylate) monolith in-tube solid-phase microextraction applied to simultaneous analysis of some amphetamine derivatives in urine by capillary zone electrophoresis. Electrophoresis 2005; 26:3141-50. [PMID: 16041709 DOI: 10.1002/elps.200500043] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A method based on in-tube solid-phase microextraction and capillary zone electrophoresis (CZE) was proposed for simultaneously determining four amphetamines (amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, and 3,4-methylenedioxymethamphetamine) in urine. A poly(methacrylic acid-ethylene glycol dimethacrylate) monolithic capillary column, which can provide sufficient extraction efficiency, was introduced for the extraction of amphetamines from urine samples. The hydrophobic main chains and acidic pendant groups of the monolithic column make it a superior material for extraction of basic analytes from aqueous matrix. After extraction, the samples were analyzed by CZE. The best separation was achieved using a buffer composed of 0.1 M disodium hydrogen phosphate (adjusted to pH 4.5 with 1 M hydrochloric acid) and 20% methanol v/v, with a temperature and voltage of 25 degrees C and 20 kV, respectively. By applying electrokinetic injection with field-amplified sample stacking, detection limits of 25-34 microg/L were achieved. Excellent method of reproducibility was found over a linear range of 0.1-5 mg/L. Determination of these analytes from abusers' urine sample was also demonstrated.
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Affiliation(s)
- Fang Wei
- Department of Chemistry, Wuhan University, Wuhan, HuBei, P. R. China
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40
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Djozan D, Amir-Zehni M. Determination of L-Dopa and L-Dopamine in Aqueous Solutions Using In-Loop SPME Coupled with LC. Chromatographia 2005. [DOI: 10.1365/s10337-005-0587-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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41
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Ordered mesoporous silica coated capillary for in-tube solid phase microextraction coupled to high performance liquid chromatography. Anal Chim Acta 2005. [DOI: 10.1016/j.aca.2005.04.024] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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42
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Nowak R, Hawrył M. Application of densitometry to the determination of catechin in rose-hip extracts. JPC-J PLANAR CHROMAT 2005. [DOI: 10.1556/jpc.18.2005.3.9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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43
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Vovk I, Simonovska B, Vuorela H. Separation of eight selected flavan-3-ols on cellulose thin-layer chromatographic plates. J Chromatogr A 2005; 1077:188-94. [PMID: 16001555 DOI: 10.1016/j.chroma.2005.03.096] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The potential of microcristaline cellulose as sorbent in the separation of eight compounds: (+)-catechin (C), (-)-epicatechin (EC), (-)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), (-)-epigallocatechin gallate (EGCg), procyanidin B1 and procyanidin B2 was studied. Cellulose HPTLC plates prewashed in water (not necessary, when water was used as developing solvent) and dried with a hair dryer, bandwise application and development in horizontal developing chamber (sandwich configuration) gave the best results. Detection was performed using vanillin-H3PO4 reagent. Four new developing solvent systems were proposed: water, 1-propanol-water (20:80, v/v), 1-propanol-water-acetic acid (4:2:1, v/v) and 1-propanol-water-acetic acid (20:80:1, v/v), and at least two of them were needed for the differentiation between all eight compounds. Surprisingly, water enabled the separation of epimers C from EC and GC from EGC, as well as the dimers procianidin B1 and B2. Additionally, C, EGC, B1 and B2 were separated from all the other compounds. The best choice for developing solvent is given for each of the studied compounds. The best separation of the five main catechins (EC, GC, EGC, ECg, EGCg) present in green tea extract was achieved using 1-propanol-water-acetic acid (20:80:1, v/v). The chromatograms of oak bark extract developed in solvents with higher water content (1-propanol-water (1:4, v/v) and 1-propanol-water-acetic acid (20:80:1, v/v)) showed less bands than chromatograms developed in solvents with higher organic modifier content (e.g. 1-propanol-water-acetic acid (4:2:1, v/v)). It was proved that such behavior was due to the presence of procyanidins beside the main component catechin.
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Affiliation(s)
- Irena Vovk
- Laboratory for Food Chemistry, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia.
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44
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Hirayama Y, Ohmichi M, Tatsumoto H. Simple and Rapid Determination of Golf Course Pesticides by In-Tube Solid-Phase Microextraction Coupled with Liquid Chromatography. ACTA ACUST UNITED AC 2005. [DOI: 10.1248/jhs.51.526] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | | | - Hideki Tatsumoto
- Department of Materials Technology, Faculty of Engineering, Chiba University
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45
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Fan Y, Feng YQ, Da SL, Wang ZH. In-tube solid phase microextraction using a β-cyclodextrin coated capillary coupled to high performance liquid chromatography for determination of non-steroidal anti-inflammatory drugs in urine samples. Talanta 2005; 65:111-7. [DOI: 10.1016/j.talanta.2004.05.040] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Revised: 04/30/2004] [Accepted: 05/18/2004] [Indexed: 11/26/2022]
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46
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Djozan D, Amir-Zehni M. In-Loop Solid-Phase Microextraction Coupled with High Performance Liquid Chromatography. Chromatographia 2004. [DOI: 10.1365/s10337-004-0402-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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47
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Wardencki W, Michulec M, Curylo J. A review of theoretical and practical aspects of solid-phase microextraction in food analysis. Int J Food Sci Technol 2004. [DOI: 10.1111/j.1365-2621.2004.00839.x] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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48
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Saito Y, Tahara A, Ogawa M, Imaizumi M, Ban K, Wada H, Jinno K. Polymer-Coated Fibrous Stationary Phases in Packed-Capillary Gas Chromatography. ANAL SCI 2004; 20:335-9. [PMID: 15055962 DOI: 10.2116/analsci.20.335] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Fibrous synthetic polymers have been introduced as the support material for packed capillaries in gas chromatography. The filaments of the polymers were packed longitudinally into a fused-silica capillary, followed by the conventional coating process for open-tubular capillaries. With various polysiloxane-based polymeric materials coated onto these filaments, it was demonstrated that the retentivity was significantly improved over conventional wall-coated capillaries of the same length and that the selectivity can be tuned by selecting different coating materials chosen for the various purposes. The results clearly showed the contribution of the fibrous support and the polymer-coating to the retention of analytes. They also showed the bright possibility for a novel usage of fine fibrous polymers as the support material, which can be combined with a newly-synthesized coating materials designed for particular separations.
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Affiliation(s)
- Yoshihiro Saito
- School of Materials Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
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49
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Abstract
Miniaturized sample preparation methods designed as the sample pretreatment for liquid phase separations, such as liquid chromatography, capillary electrophoresis and capillary electrochromatography, have been reviewed especially for the on-line coupling of the sample preparation process and the separation process. The development of the desorption interfaces for the effective combining of the sample preparation and subsequent liquid phase separations is briefly described along with the applications of the combined analytical systems to the analysis of complex sample mixtures such as biological and environmental matrices. Novel use of fine polymeric filaments as the extraction medium for microscale liquid phase separation methods are investigated and a comparison is made with other sample preparation techniques. Polymer coating onto the fibrous material is also introduced to further develop microscale sample preparation methods with improved extraction performance. Several other microscale sample preparation methods having a potential compatibility to the liquid phase separations are also described for future applications of these techniques.
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Affiliation(s)
- Yoshihiro Saito
- School of Materials Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
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50
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Mitani K, Narimatsu S, Kataoka H. Determination of daidzein and genistein in soybean foods by automated on-line in-tube solid-phase microextraction coupled to high-performance liquid chromatography. J Chromatogr A 2003; 986:169-77. [PMID: 12597624 DOI: 10.1016/s0021-9673(02)02014-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
An automated on-line method for the determination of the isoflavones, daidzein and genistein, was developed using in-tube solid-phase microextraction coupled to high-performance liquid chromatography (in-tube SPME-HPLC). In-tube SPME is a new extraction technique for organic compounds in aqueous samples, in which analytes are extracted from the sample directly into an open tubular capillary by repeated draw/eject cycles of sample solution. Daidzein, genistein and their glucosides tested in this study were clearly separated within 8 min by HPLC using an XDB-C8 column with diode array detection. In order to optimize the extraction of these compounds, several in-tube SPME parameters were examined. The glucosides daidzin and genistin were analyzed as aglycones after hydrolysis because the glucosides were not concentrated by in-tube SPME. The optimum extraction conditions for daidzein and genistein were obtained with 20 draw/eject cycles of 40 microl of sample using a Supel-Q porous layer open tubular capillary column. The extracted compounds were easily desorbed from the capillary by mobile phase flow, and carryover was not observed. Using the in-tube SPME-HPLC method, the calibration curves of these compounds were linear in the range 5-200 ng/ml, with a correlation coefficient above 0.9999 (n = 18), and the detection limits (S/N = 3) were 0.4-0.5 ng/ml. This method was successfully applied to the analysis of soybean foods without interference peaks. The recoveries of aglycones and glucosides spiked into food samples were above 97%.
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Affiliation(s)
- Kurie Mitani
- Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700-8530, Japan
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