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Lin Z, Wang Q, Zhou Y, Shackman JG. Trapping mode two-dimensional liquid chromatography for quantitative low-level impurity enrichment in pharmaceutical development. J Chromatogr A 2023; 1700:464043. [PMID: 37172541 DOI: 10.1016/j.chroma.2023.464043] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/20/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023]
Abstract
Trapping mode two-dimensional liquid chromatography (2D-LC) has recently found applications in pharmaceutical analysis to clean, refocus, and enrich analytes. Given its enrichment capability, 2D-LC with multiple trappings is appealing for low-level impurity monitoring that cannot be solved by single dimensional LC (1D-LC) or unenriched 2D-LC analysis. However, the quantitative features of multi-trapping 2D-LC remain largely unknown at impurity levels from parts-per-million (ppm) to 0.15% (w/w). We present a simple heart-cutting trapping mode 2D-LC workflow using only common components and software found in typical off-the-shelf 1D-LC instruments. This robust, turn-key system's quantitative capabilities were evaluated using a variety of standard markers, demonstrating linear enrichment for up to 20 trapping cycles and achieving a recovery of over 97.0%. Next, the trapping system was applied to several real-world low-level impurity pharmaceutical case studies including (1) the identification of two unknown impurities at sub-ppm levels resulting in material discoloration, (2) the discovery of a new impurity at 0.05% (w/w) co-eluted with a known impurity, making the undesired summation above the target specification, and (3) the quantification of a potential mutagenic impurity at 10-ppm level in a poorly soluble substrate. The recovery in all studies was better than 97.0% with RSD lower than 3.0%, demonstrating accuracy and precision of the 2D-LC trapping workflow. As no specialized equipment or software is required, we envision that the system could be used to develop low-impurity monitoring methods suitable for validation and potential execution in quality-control laboratories.
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Affiliation(s)
- Ziqing Lin
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA.
| | - Qinggang Wang
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA
| | - Yiyang Zhou
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA
| | - Jonathan G Shackman
- Bristol Myers Squibb Company, Chemical Process Development, One Squibb Drive, New Brunswick, NJ 08903, USA
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Bernardo-Bermejo S, Marina ML, Castro-Puyana M. A rapid electrokinetic chromatography method using short-end injection for the enantioselective separation of tryptophan. Microchem J 2021. [DOI: 10.1016/j.microc.2021.106508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Lomenova A, Hroboňová K. Application of achiral-chiral two-dimensional HPLC for separation of phenylalanine and tryptophan enantiomers in dietary supplement. Biomed Chromatogr 2020; 35:e4972. [PMID: 32840880 DOI: 10.1002/bmc.4972] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/14/2020] [Accepted: 08/21/2020] [Indexed: 11/11/2022]
Abstract
This study developed a two-dimensional heart-cutting LC method for the separation of amino acid enantiomers. Two approaches for achiral separation of amino acids, phenylalanine and tryptophan, were selected. Amino acids were separated on C18 or hydrophilic interaction liquid chromatography (HILIC) columns in first dimension after their enantiomer separation on a teicoplanin chiral column in second dimension. Mobile phases for both separation systems were optimized by testing different types of organic modifiers, concentrations of ion-pair agent (sodium 1-octanesulfonate), and ionic modifier (ammonium acetate). The resolution of enantiomers higher than 1.5 for both amino acids was achieved using a C18-teicoplanin coupled column separation system with mobile phases methanol/2 mM sodium 1-octanesulfonate (10:90 and 75:25, step gradient between achiral and chiral columns, respectively). The lower resolution of amino acid enantiomers (RS ˃ 0.9), but higher column efficiency, was achieved on a HILIC-teicoplanin separation system with mobile phases acetonitrile/50 mM ammonium acetate (90:10 and 80:20, step gradient between achiral and chiral columns, respectively). The developed heart-cutting 2D-LC methods were validated in terms of linearity, limit of detection, limit of quantification, precision, and accuracy. The results suggested that the developed methods were applicable for the simultaneous determination of amino acid enantiomers in the dietary supplement. The sample contained l-phenylalanine and l-tryptophan.
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Affiliation(s)
- Anna Lomenova
- Faculty of Chemical and Food Technology, Institute of Analytical Chemistry, Slovak University of Technology in Bratislava, Bratislava, Slovak Republic
| | - Katarína Hroboňová
- Faculty of Chemical and Food Technology, Institute of Analytical Chemistry, Slovak University of Technology in Bratislava, Bratislava, Slovak Republic
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D-amino acids in foods. Appl Microbiol Biotechnol 2019; 104:555-574. [PMID: 31832715 DOI: 10.1007/s00253-019-10264-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 11/12/2019] [Accepted: 11/22/2019] [Indexed: 02/07/2023]
Abstract
With the only exception of glycine, all amino acids exist in two specular structures which are mirror images of each other, called D-(dextro) and L-(levo) enantiomers. During evolution, L-amino acids were preferred for protein synthesis and main metabolism; however, the D-amino acids (D-AAs) acquired different and specific functions in different organisms (from playing a structural role in the peptidoglycan of the bacterial cell wall to modulating neurotransmission in mammalian brain). With the advent of sophisticated and sensitive analytical techniques, it was established during the past few decades that many foods contain considerable amounts of D-AAs: we consume more than 100 mg of D-AAs every day. D-AAs are present in a variety of foodstuffs, where they fulfill a relevant role in producing differences in taste and flavor and in their antimicrobial and antiaging properties from the corresponding L-enantiomers. In this review, we report on the derivation of D-AAs in foods, mainly originating from the starting materials, fermentation processes, racemization during food processing, or contamination. We then focus on leading-edge methods to identify and quantify D-AAs in foods. Finally, current knowledge concerning the effect of D-AAs on the nutritional state and human health is summarized, highlighting some positive and negative effects. Notwithstanding recent progress in D-AA research, the relationships between presence and nutritional value of D-AAs in foods represent a main scientific issue with interesting economic impact in the near future.
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Montero L, Herrero M. Two-dimensional liquid chromatography approaches in Foodomics – A review. Anal Chim Acta 2019; 1083:1-18. [DOI: 10.1016/j.aca.2019.07.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 07/17/2019] [Accepted: 07/19/2019] [Indexed: 01/29/2023]
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8
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Influence of irradiation and moringa leaf powder on the amino acid and fatty acid profiles of chicken meat stored under various packaging materials. J FOOD PROCESS PRES 2019. [DOI: 10.1111/jfpp.14166] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Lomenova A, Hroboňová K. Comparison of HPLC Separation of Phenylalanine Enantiomers on Different Types of Chiral Stationary Phases. FOOD ANAL METHOD 2018. [DOI: 10.1007/s12161-018-1308-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Jo Y, An KA, Arshad MS, Kwon JH. Effects of e-beam irradiation on amino acids, fatty acids, and volatiles of smoked duck meat during storage. INNOV FOOD SCI EMERG 2018. [DOI: 10.1016/j.ifset.2017.12.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Song YY, Song XD, Yuan H, Cheng CJ. Thermo-responsive adsorption and separation of amino acid enantiomers using smart polymer-brush-modified magnetic nanoparticles. NEW J CHEM 2016. [DOI: 10.1039/c5nj03516c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel type of multifunctional magnetic nanoparticle with highly chiral recognition capability, excellent thermo-sensitive adsorption and decomplexation properties toward amino acid enantiomers, and recyclability was developed in this study.
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Affiliation(s)
- Ya-Ya Song
- College of Chemistry and Environment Protection Engineering
- Southwest University for Nationalities
- Chengdu
- P. R. China
| | - Xiao-Dong Song
- College of Chemistry and Environment Protection Engineering
- Southwest University for Nationalities
- Chengdu
- P. R. China
| | - Heng Yuan
- College of Chemistry and Environment Protection Engineering
- Southwest University for Nationalities
- Chengdu
- P. R. China
| | - Chang-Jing Cheng
- College of Chemistry and Environment Protection Engineering
- Southwest University for Nationalities
- Chengdu
- P. R. China
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Song YL, Jing WH, Du G, Yang FQ, Yan R, Wang YT. Qualitative analysis and enantiospecific determination of angular-type pyranocoumarins in Peucedani Radix using achiral and chiral liquid chromatography coupled with tandem mass spectrometry. J Chromatogr A 2014; 1338:24-37. [PMID: 24630501 DOI: 10.1016/j.chroma.2014.01.078] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 01/30/2014] [Accepted: 01/31/2014] [Indexed: 10/25/2022]
Abstract
Angular-type pyranocoumarins (APs), the derivatives of khellactone, are widely documented as the main active constituents in Peucedani Radix (Chinese name: Qian-hu). Owing to the natural occurrence of chiral centers, enantiomers of APs are extensively distributed in the original plant, and enantioselective performances have been definitely demonstrated for these enantiomers. In current study, the chemical characterization of the major and minor APs in Peucedani Radix was performed using ultra high performance liquid chromatography coupled with diode array detector and hybrid ion trap-orbitrap mass spectrometry. On the other hand, a heart-cut two-dimensional achiral-chiral liquid chromatography combining triple quadropole-linear ion trap mass spectrometry system (2D LC-MS/MS) was developed for simultaneous enantiospecific quantification of eighteen coumarins, including seven pairs of enantiomers. Eleven APs (1-11) were recruited to propose UV absorption characteristics and electrospray ionization fragmentation patterns of APs. A total of 42 components were categorized into APs based on their UV spectral properties and identified according to the proposed mass fragmentation pathways, while two linear-type furanocoumarins (12-13) were unambiguously assigned by further purification. A Capcell core RP-C18 column was employed in the primary LC dimension to achieve efficient racemic separation for the main chemical constituents (1-9 and 12-13) in Peucedani Radix, while a Chiralpak AD-RH column was utilized in the secondary dimension to contribute enantioselective separation for seven enantiomerically enriched components (1, 3 and 5-9). Collectively, the results provided the chemical evidences for revealing the material basis of the therapeutic effects of Peucedani Radix, and the developed 2D LC-MS/MS system in the present study is expected to be an ideal tool for the quality control of Peucedani Radix as well as a reliable technique for complex matrices containing both achiral and chiral components.
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Affiliation(s)
- Y L Song
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - W H Jing
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - G Du
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - F Q Yang
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing, China
| | - R Yan
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China
| | - Y T Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macao, China.
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León-González ME, Rosales-Conrado N, Pérez-Arribas LV, Guillén-Casla V. Two-dimensional liquid chromatography for direct chiral separations: a review. Biomed Chromatogr 2013; 28:59-83. [DOI: 10.1002/bmc.3007] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 07/03/2013] [Accepted: 07/03/2013] [Indexed: 01/23/2023]
Affiliation(s)
- María Eugenia León-González
- Analytical Chemistry Department, Faculty of Chemistry; Complutense University of Madrid; E-28040 Madrid Spain
| | - Noelia Rosales-Conrado
- Analytical Chemistry Department, Faculty of Chemistry; Complutense University of Madrid; E-28040 Madrid Spain
| | - Luis Vicente Pérez-Arribas
- Analytical Chemistry Department, Faculty of Chemistry; Complutense University of Madrid; E-28040 Madrid Spain
| | - Vanesa Guillén-Casla
- Analytical Chemistry Department, Faculty of Chemistry; Complutense University of Madrid; E-28040 Madrid Spain
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Analysis of irradiated cooked ham by direct introduction into the programmable temperature vaporizer of a multidimensional gas chromatography system. Food Chem 2013; 139:241-5. [DOI: 10.1016/j.foodchem.2013.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 10/01/2012] [Accepted: 01/02/2013] [Indexed: 11/20/2022]
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Zhang K, Li Y, Tsang M, Chetwyn NP. Analysis of pharmaceutical impurities using multi-heartcutting 2D LC coupled with UV-charged aerosol MS detection. J Sep Sci 2013; 36:2986-92. [DOI: 10.1002/jssc.201300493] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 06/06/2013] [Accepted: 06/10/2013] [Indexed: 11/09/2022]
Affiliation(s)
- Kelly Zhang
- Small Molecule Pharmaceutical Sciences; Genentech; South San Francisco CA USA
| | - Yi Li
- Small Molecule Pharmaceutical Sciences; Genentech; South San Francisco CA USA
| | - Midco Tsang
- Small Molecule Pharmaceutical Sciences; Genentech; South San Francisco CA USA
| | - Nik P. Chetwyn
- Small Molecule Pharmaceutical Sciences; Genentech; South San Francisco CA USA
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Ma S, Grinberg N, Haddad N, Rodriguez S, Busacca CA, Fandrick K, Lee H, Song JJ, Yee N, Krishnamurthy D, Senanayake CH, Wang J, Trenck J, Mendonsa S, Claise PR, Gilman RJ, Evers TH. Heart-Cutting Two-Dimensional Ultrahigh-Pressure Liquid Chromatography for Process Development: Asymmetric Reaction Monitoring. Org Process Res Dev 2013. [DOI: 10.1021/op300266j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Peter R. Claise
- Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757-3696, United States
| | - Roger J. Gilman
- Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757-3696, United States
| | - Thomas H. Evers
- Waters Corporation, 34 Maple Street, Milford, Massachusetts 01757-3696, United States
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Chiral Determination of Salbutamol, Salmeterol and Atenolol by Two-Dimensional LC–LC: Application to Urine Samples. Chromatographia 2012. [DOI: 10.1007/s10337-012-2353-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Ilisz I, Aranyi A, Pataj Z, Péter A. Recent advances in the direct and indirect liquid chromatographic enantioseparation of amino acids and related compounds: A review. J Pharm Biomed Anal 2012; 69:28-41. [DOI: 10.1016/j.jpba.2012.01.020] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 01/18/2012] [Accepted: 01/19/2012] [Indexed: 12/01/2022]
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Venkatramani CJ, Wigman L, Mistry K, Chetwyn N. Simultaneous, sequential quantitative achiral-chiral analysis by two-dimensional liquid chromatography. J Sep Sci 2012; 35:1748-54. [DOI: 10.1002/jssc.201200005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Larry Wigman
- Small Molecules Pharmaceutical Science; Genentech Inc.; South San Francisco CA USA
| | - Kavita Mistry
- Technical Regulatory; Genentech Inc.; South San Francisco CA USA
| | - Nicholas Chetwyn
- Small Molecules Pharmaceutical Science; Genentech Inc.; South San Francisco CA USA
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Abstract
AbstractEnantiomers (stereoisomers) can exhibit substantially different properties if present in chiral environments. Since chirality is a basic property of nature, the different behaviors of the individual enantiomers must be carefully studied and properly treated. Therefore, enantioselective separations are a very important part of separation science. To achieve the separation of enantiomers, an enantioselective environment must be created by the addition of a chiral selector to the separation system. Many chiral selectors have been designed and used in various fields, such as the analyses of drugs, food constituents and agrochemicals. The most popular have become the chiral selectors and/or chiral stationary phases that are of general use, i.e., are applicable in various separation systems and allow for chiral separation of structurally different compounds. This review covers the most important chiral selectors / chiral stationary phases described and applied in high performance liquid chromatography and capillary electrophoresis during the period of the last three years (2008–2011).
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Eto S, Yamaguchi M, Bounoshita M, Mizukoshi T, Miyano H. High-throughput comprehensive analysis of d- and l-amino acids using ultra-high performance liquid chromatography with a circular dichroism (CD) detector and its application to food samples. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:3317-25. [DOI: 10.1016/j.jchromb.2011.07.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 07/13/2011] [Accepted: 07/18/2011] [Indexed: 02/08/2023]
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Qu P, Zhang L, Sheng J, Lei J, Ju H. Convenient enantioseparation by monolithic imprinted capillary clamped in a chip with electrochemical detection. Electrophoresis 2011; 32:1522-9. [DOI: 10.1002/elps.201000655] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 03/07/2011] [Accepted: 03/07/2011] [Indexed: 11/05/2022]
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Guillén-Casla V, Rosales-Conrado N, León-González ME, Pérez-Arribas LV, Polo-Díez LM. Principal component analysis (PCA) and multiple linear regression (MLR) statistical tools to evaluate the effect of E-beam irradiation on ready-to-eat food. J Food Compost Anal 2011. [DOI: 10.1016/j.jfca.2010.11.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Cheng C, Wu SC. Simultaneous analysis of aspartame and its hydrolysis products of Coca-Cola Zero by on-line postcolumn derivation fluorescence detection and ultraviolet detection coupled two-dimensional high-performance liquid chromatography. J Chromatogr A 2011; 1218:2976-83. [PMID: 21481403 DOI: 10.1016/j.chroma.2011.03.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 02/01/2011] [Accepted: 03/15/2011] [Indexed: 10/18/2022]
Abstract
An innovative two-dimensional high-performance liquid chromatography system was developed for the simultaneous analysis of aspartame and its hydrolysis products of Coca-Cola Zero. A C8 reversed-phase chromatographic column with ultraviolet detection was used as the first dimension for the determination of aspartame, and a ligand-exchange chromatographic column with on-line postcolumn derivation fluorescence detection was employed as the second dimension for the analysis of amino acid enantiomers. The fluorimetric derivative reagent of amino acid enantiomers was o-phthaldialdehyde. The hydrolysis of aspartame in Coca-Cola Zero was induced by electric-heating or microwave heating. Aspartame was quantified by the matrix matched external standard calibration curve with a linear concentration range of 0-50 μg mL(-1) (r(2)=0.9984). The limit of detection (LOD) and the limit of quantification (LOQ) were 1.3 μg mL(-1) and 4.3 μg mL(-1), respectively. The amino acid enantiomers was analyzed by the matrix matched internal standard calibration method (D-leucine as the internal standard) with a linear concentration range of 0-10 μg mL(-1) (r(2)=0.9988-0.9997). The LODs and LOQs for L- and D-aspartic acid and L- and D-phenylalanine were 0.16-0.17 μg mL(-1) and 0.52-0.55 μg mL(-1), respectively, that was 12-13 times more sensitive than ultraviolet detection. The overall analysis accuracy for aspartame and amino acid enantiomers was 90.2-99.2% and 90.4-96.2%, respectively. The overall analysis precision for aspartame and amino acid enantiomers was 0.1-1.7% and 0.5-6.7%, respectively. Generally, the extent of aspartame hydrolysis increases with the increase of electro-thermal temperature, microwave power, and the duration of hydrolysis time. D-aspartic acid and D-phenylalanine can be observed with the electro-thermal racemization at the hydrolysis temperature 120°C for 1 day and only D-aspartic acid can be observed at the hydrolysis temperature 90°C for 2 and 3 days. For the microwave induced hydrolysis, only L-aspartic acid was detected at the power 560 W for 1 min and 320 W for 3 min.
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Affiliation(s)
- Cheanyeh Cheng
- Department of Chemistry, Chung Yuan Christian University, Chungli, Taiwan, ROC.
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Qu P, Lei J, Sheng J, Zhang L, Ju H. Simultaneous multiple enantioseparation with a one-pot imprinted microfluidic channel by microchip capillary electrochromatography. Analyst 2011; 136:920-6. [DOI: 10.1039/c0an00559b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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