151
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Wang Z, Ouyang J, Baeyens WR. Recent developments of enantioseparation techniques for adrenergic drugs using liquid chromatography and capillary electrophoresis: A review. J Chromatogr B Analyt Technol Biomed Life Sci 2008; 862:1-14. [DOI: 10.1016/j.jchromb.2007.11.034] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Revised: 10/20/2007] [Accepted: 11/23/2007] [Indexed: 10/22/2022]
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152
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Pan J, Zhang S, Yan L, Tai J, Xiao Q, Zou K, Zhou Y, Wu J. Separation of flavanone enantiomers and flavanone glucoside diastereomers from Balanophora involucrata Hook. f. by capillary electrophoresis and reversed-phase high-performance liquid chromatography on a C18 column. J Chromatogr A 2008; 1185:117-29. [PMID: 18291407 DOI: 10.1016/j.chroma.2008.01.049] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2007] [Revised: 12/28/2007] [Accepted: 01/16/2008] [Indexed: 11/30/2022]
Abstract
A pair of flavanone glucoside diastereomers, (2R)- and (2S)-eriodictyol-5-O-beta-d-glucopyranoside (1a, 1b), was successfully separated by RP-C(18) high-performance liquid chromatography from Balanophora involucrata Hook. f. Some other compounds, including a pair of flavanone enantiomers, (2R)- and (2S)-eriodictyol (2a, 2b), and a pair of flavanone glucoside diastereomers, (2R)- and (2S)-eriodictyol-7-O-beta-d-glucopyranoside(3a, 3b), were separated by capillary electrophoresis from the same plant. The absolute configurations at C-2 of 1a and 1b were determined based on their circular dichroism spectra. Enzymatic hydrolysis of 1a and 1b by beta-d-glucosidase afforded (2R)- and (2S)-eriodictyol, respectively, which were used as the authentic standards for co-elution to determine the migration order of the enantiomers, 2a and 2b. We also report the first example of identifying the migration order of 2a and 2b and resolving the separation of 3a and 3b by capillary electrophoresis. In addition, 1a was unambiguously characterized for the first time by NMR spectra.
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Affiliation(s)
- Jianyu Pan
- Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
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153
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Mandrioli R, Raggi MA. Electrodriven methods for the enantioseparation of second-generation antidepressant drugs: An update. Electrophoresis 2008; 29:252-9. [DOI: 10.1002/elps.200700500] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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154
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Elbashir AA, Saad B, Mohamed Ali AS, Saleh MI, Aboul‐Enein HY. Determination of Ofloxacin Enantiomers in Pharmaceutical Formulations by Capillary Electrophoresis. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070701780631] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Abdalla A. Elbashir
- a School of Chemical Sciences , Universiti Sains Malaysia , Penang, Malaysia
| | - Bahruddin Saad
- a School of Chemical Sciences , Universiti Sains Malaysia , Penang, Malaysia
| | | | | | - Hassan Y. Aboul‐Enein
- b Pharmaceutical and Medicinal Chemistry Department , National Research Centre , Dokki, Cairo, Egypt
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155
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Determination of enantiomeric impurity of linezolid by capillary electrophoresis using heptakis-(2,3-diacetyl-6-sulfato)-beta-cyclodextrin. J Chromatogr A 2007; 1180:179-86. [PMID: 18164025 DOI: 10.1016/j.chroma.2007.11.110] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 11/28/2007] [Accepted: 11/30/2007] [Indexed: 10/22/2022]
Abstract
A method for the enantioseparation of linezolid, the first compound of a truly new class of antibiotics-the oxazolidinones, was developed. The elaborated method of linezolid enantiomers separation was successfully performed using an anionic single-isomer cyclodextrin-heptakis-(2,3-diacetyl-6-sulfato)-beta-cyclodextrin (HDAS-beta-CD) as a resolving agent with the help of the charged resolving agent migration model (CHARM model). The best results were obtained with 27.5mM HDAS-beta-CD dissolved in 50mM borate buffer, pH 9.0, 15 degrees C, normal polarity. The facile strategies for the reversal of the enantiomers elution order are also described. Afterwards, the optimized method was validated in terms of sensitivity, linearity, accuracy and precision.
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156
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Bao Y, Huang J, Li T, Armstrong DW. Evaluation of Pentaproline-Based Chiral Stationary Phase by LC. Chromatographia 2007. [DOI: 10.1365/s10337-007-0438-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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157
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Zhou L, Lin Z, Reamer RA, Mao B, Ge Z. Stereoisomeric separation of pharmaceutical compounds using CE with a chiral crown ether. Electrophoresis 2007; 28:2658-66. [PMID: 17657760 DOI: 10.1002/elps.200600788] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Optical pure (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid, a chiral crown ether, was successfully used as a chiral selector for the stereoisomeric separation of numerous real pharmaceutical compounds. Both practical and mechanistic aspects were described. Effects of chiral selector concentration under different pH values of BGE were discussed. Chiral recognition for the enantiomeric compounds with (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid was investigated through model compounds using CE and infrared spectroscopic techniques. Relations between the enantioselectivity of the chiral crown ether and the structural features of the studied compounds were also investigated. Unusual resolutions of compound-p and its enantiomer as well as compound-o and its 2b epimer were described. These compounds contained only tertiary amine, believed to be nonbinding with crown ethers in general. The possible mechanisms for the interaction between compound-o and the chiral crown ether were investigated using CE, electrospray MS (ESI-MS), and proton ((1)H) NMR spectroscopy. All experiments provided clear evidence that binding between compound-o and the chiral crown ether had occurred. ESI-MS spectra indicated that the complexes had a 1:1 stoichiometric ratio. The advantages and disadvantages of using chiral crown ether for stereoisomeric separations were compared with those using sulfated CDs.
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Affiliation(s)
- Lili Zhou
- Merck Research Laboratories, Merck and Co. Inc., Rahway, NJ 07065-0900, USA.
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158
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Contributions of capillary electrophoresis to neuroscience. J Chromatogr A 2007; 1184:144-58. [PMID: 18054026 DOI: 10.1016/j.chroma.2007.10.098] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 10/16/2007] [Accepted: 10/29/2007] [Indexed: 11/23/2022]
Abstract
Capillary electrophoresis (CE) is a small-volume separation approach amenable to the analysis of complex samples for their small molecule, peptide and protein content. A number of the features of CE make it a method of choice for addressing questions related to neurochemistry. The figures of merit inherent to CE that make it well suited for studying cell-to-cell and intracellular signaling include small sample volumes, high separation efficiency, the ability for online analyte concentration, and compatibility with sensitive and high-information content detection methods. A variety of instrumental aspects are detailed, including detection methods and sampling techniques that are particularly useful for the analysis of signaling molecules. Studies that have used these techniques to increase our understanding of neurobiology are emphasized throughout. One notable application is single neuron chemical analysis, a research area that has been greatly advanced by CE.
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159
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Liao WS, Lin CH, Chen CY, Kuo CM, Liu YC, Wu JC, Lin CE. Enantioseparation of phenothiazines in CD-modified CZE using single isomer sulfated CD as a chiral selector. Electrophoresis 2007; 28:3922-9. [DOI: 10.1002/elps.200700059] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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160
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Shpigun OA, Ananieva IA, Budanova NY, Shapovalova EN. Use of cyclodextrins for separation of enantiomers. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc2003v072n12abeh000817] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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161
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Nilsson C, Birnbaum S, Nilsson S. Use of nanoparticles in capillary and microchip electrochromatography. J Chromatogr A 2007; 1168:212-24; discussion 211. [PMID: 17719051 DOI: 10.1016/j.chroma.2007.07.018] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Revised: 05/26/2007] [Accepted: 07/09/2007] [Indexed: 12/15/2022]
Abstract
Applications of nanoparticles are of rising interest in separation science, due to their favorable surface-to-volume ratio as well as their applicability in miniaturization. A stationary phase with large surface area in combination with an electroosmotic flow-driven system has great potential in a highly efficient separation system. This review covers the use of various nanoparticles as stationary or pseudostationary phase in capillary and microchip electrochromatography. The use of nanoparticles in pseudostationary phase capillary electrochromatography and open-tubular capillary electrochromatography are thoroughly discussed. The stationary and pseudostationary phases that are described include polymer nanoparticles, gold nanoparticles, silica nanoparticles, fullerenes and carbon nanotubes.
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Affiliation(s)
- Christian Nilsson
- Pure and Applied Biochemistry, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
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162
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Zhao Y, Yang XB, Wang QF, Sun XL, Jiang R, Zhang SY. Determination of Enantiomeric Excess of Aromatic 1,2-Diols with HP-β-Cyclodextrin as Chiral Selector by CE. Chromatographia 2007. [DOI: 10.1365/s10337-007-0366-8] [Citation(s) in RCA: 9] [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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163
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Lo Meo P, D'Anna F, Riela S, Gruttadauria M, Noto R. Host–guest interactions involving cyclodextrins: useful complementary insights achieved by polarimetry. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.06.065] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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164
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Liu Y, Lantz AW, Armstrong DW. High Efficiency Liquid and Super‐/Subcritical Fluid‐Based Enantiomeric Separations: An Overview. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120030600] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Ying Liu
- a Department of Chemistry , Iowa State University , Ames , Iowa , 50011‐3111 , USA
| | - Andrew W. Lantz
- a Department of Chemistry , Iowa State University , Ames , Iowa , 50011‐3111 , USA
| | - Daniel W. Armstrong
- a Department of Chemistry , Iowa State University , Ames , Iowa , 50011‐3111 , USA
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165
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Kodama S, Yamamoto A, Sato A, Suzuki K, Yamashita T, Kemmei T, Taga A, Hayakawa K. Enantioseparation of isoxanthohumol in beer by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:6547-52. [PMID: 17629302 DOI: 10.1021/jf0710478] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Chiral resolution of isoxanthohumol (IX) in beer samples was performed by hydroxypropyl-gamma-cyclodextrin-modified micellar electrokinetic chromatography. The optimum running conditions were found to be 20 mM phosphate buffer (pH 7.0) containing 45 mM hydroxypropyl-gamma-cyclodextrin and 100 mM sodium dodecyl sulfate with an effective voltage of +20 kV at 20 degrees C using direct detection at 210, 295, and 370 nm. IX was detected in 12 beer samples and the total levels of (+)- and (-)-IX ranged from 0.15 to 1.4 mg/L. But the amount of xanthohumol (XN) was below the detection limit (0.017 mg/L). Each level of (-)-IX was almost the same as that of (+)-IX, suggesting that IX was a racemic mixture in these beer samples. The racemization of IX in beer could be attributed to the production of a racemic mixture from XN during boiling and to the fact that IX enantiomers were easily interconverted.
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Affiliation(s)
- Shuji Kodama
- Toyama Institute of Health, 17-1 Nakataikoyama, Imizu, Toyama 939-0363, Japan.
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166
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Aturki Z, Scotti V, D'Orazio G, Rocco A, Raggi MA, Fanali S. Enantioselective separation of the novel antidepressant mirtazapine and its main metabolites by CEC. Electrophoresis 2007; 28:2717-25. [PMID: 17592613 DOI: 10.1002/elps.200600731] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In this work, the simultaneous enantioseparation of the second-generation antidepressant drug mirtazapine and its main metabolites 8-hydroxymirtazapine and N-desmethylmirtazapine by chiral CEC is reported. The separation of all enantiomers under study was achieved employing a capillary column packed with a vancomycin-modified diol stationary phase. With the aim to optimize the separation of the three pairs of enantiomers in the same run, different experimental parameters were studied including the mobile phase composition (buffer concentration and pH, organic modifier type and ratio, and water content), stationary phase composition, and capillary temperature. A capillary column packed with vancomycin mixed with silica particles in the ratio (3:1) and a mobile phase composed of 100 mM ammonium acetate buffer (pH 6)/H(2)O/MeOH/ACN (5:15:30:50, by vol.) allowed the complete enantioresolution of each pair of enantiomers but not the simultaneous separation of all the studied compounds. For this purpose, a packing bed composed of vancomycin-CSP only was tested and the baseline resolution of the three couples of enantiomers was achieved in a single run in less than 30 min, setting the applied voltage and temperature at 25 kV and 20 degrees C, respectively. In order to show the potential applicability of the developed CEC method to biomedical analysis, a study concerning precision, sensitivity, and linearity was performed. The method was then applied to the separation of the enantiomers in a human urine sample spiked with the studied compounds after suitable SPE procedure with strong cation-exchange (SCX) cartridges.
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Affiliation(s)
- Zeineb Aturki
- Istituto di Metodologie Chimiche, Consiglio Nazionale delle Ricerche, Monterotondo Scalo, Rome, Italy.
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167
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Hammitzsch-Wiedemann M, Scriba GKE. Influence of buffer substances and urea on the β-cyclodextrin-mediated chiral separation of dipeptides in CE. Electrophoresis 2007; 28:2619-28. [PMID: 17592612 DOI: 10.1002/elps.200600728] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The influence of buffering substances and urea on the beta-CD-mediated chiral separations of the dipeptides Ala-Phe and Ala-Tyr was studied in the pH range of 2.5-3.8. Only minor effects of the buffer substances on the chiral separation selectivity alpha were observed at a beta-CD concentration of 15 mg/mL. In contrast, the selectivity improved at pH 2.5 but decreased at pH 3.8 upon the addition of 2 M urea. Complexation by beta-CD resulted in a shift of the pK(a) values toward higher values which was more pronounced for the DD-enantiomers of both dipeptides than for the LL-enantiomers. Addition of urea further increased the pK(a) shift. The consequence of this pK(a) shift is an increase of the fraction of the protonated, positively charged form of the peptides which explained the improved chiral separation at pH 2.5 and the reduced selectivity at pH 3.8. A pK(a) shift by the addition of urea was also observed for N-tert-butyloxycarbonyl phenylalanine (BOC-Phe) as a model compound that is strongly complexed by beta-CD. This effect was not stereospecific. Addition of urea resulted in a decrease of the apparent complexation constants between beta-CD and the BOC-Phe enantiomers to the same extent but this did not affect the separation selectivity alpha. For chiral separations that display strong pH dependence such as peptide enantioseparations close to the pK(a) values of the compounds, urea may not solely be regarded as a solubility enhancer for beta-CD but may also influence the separation.
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168
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Znaleziona J, Petr J, Maier V, Knob R, Horakova J, Smetanova D, Sevcik J. CAPILLARY ELECTROPHORESIS AS A VERIFICATION TOOL FOR IMMUNOCHEMICAL DRUG SCREENING. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2007; 151:31-6. [PMID: 17690736 DOI: 10.5507/bp.2007.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The aim of this work was to develop a simple capillary electrophoretic method as the verification and confirmation tool in the screening analysis for amphetamines, opiates, benzodiazepines and cocaine and their metabolites for toxicological applications. METHODS 50 mM phosphate Tris pH 2.0 with 30% (v/v) of methanol was used as a background electrolyte that enabled fast separation of drugs and their metabolites in saliva and urine. Verification of the data from the electrophoretic method was done by High Performance Thin Layer Chromatography (HPTLC) and the immunochemical screening test QuikScreen. RESULTS The experimental conditions of the Capillary Electrophoresis (CE) were partially optimized (mainly the influence of concentration and types of additives, e.g. cyclodextrines, organic solvents) and validated; the method was used for analysing samples from drug abusers. CONCLUSIONS The non-instrumental, immunoassay tests could only confirm qualitative addictions and are mainly employed when the emergency detection of drugs is needed. For quantitative analysis and verification of obtained results the confirmation step is strongly recommended. The simple screening capillary zone electrophoresis method allows recognition of the most abused drugs. The agreement of the results from CE, HPTLC and QuikScreen test was more than 95%.
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Affiliation(s)
- Joanna Znaleziona
- Department of Analytical Chemistry, Faculty of Science, Palacky University, tr. Svobody 8, CZ-771 46 Olomouc, Czech Republic
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169
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Smith ML, Vorce SP, Holler JM, Shimomura E, Magluilo J, Jacobs AJ, Huestis MA. Modern instrumental methods in forensic toxicology. J Anal Toxicol 2007; 31:237-53, 8A-9A. [PMID: 17579968 PMCID: PMC2745311 DOI: 10.1093/jat/31.5.237] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
This article reviews modern analytical instrumentation in forensic toxicology for identification and quantification of drugs and toxins in biological fluids and tissues. A brief description of the theory and inherent strengths and limitations of each methodology is included. The focus is on new technologies that address current analytical limitations. A goal of this review is to encourage innovations to improve our technological capabilities and to encourage use of these analytical techniques in forensic toxicology practice.
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Affiliation(s)
- Michael L. Smith
- Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, 1413 Research Blvd., Bldg. 102, Rockville, Maryland 20850
| | - Shawn P. Vorce
- Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, 1413 Research Blvd., Bldg. 102, Rockville, Maryland 20850
| | - Justin M. Holler
- Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, 1413 Research Blvd., Bldg. 102, Rockville, Maryland 20850
| | - Eric Shimomura
- Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, 1413 Research Blvd., Bldg. 102, Rockville, Maryland 20850
| | - Joe Magluilo
- Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, 1413 Research Blvd., Bldg. 102, Rockville, Maryland 20850
| | - Aaron J. Jacobs
- Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, 1413 Research Blvd., Bldg. 102, Rockville, Maryland 20850
- Army Medical Department Board, Fort Sam Houston, Texas 78234
| | - Marilyn A. Huestis
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, 5500 Nathan Shock Drive, Baltimore, Maryland 21224
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170
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Musenga A, Mandrioli R, Morganti E, Fanali S, Raggi MA. Enantioselective analysis of amisulpride in pharmaceutical formulations by means of capillary electrophoresis. J Pharm Biomed Anal 2007; 46:966-70. [PMID: 17606354 DOI: 10.1016/j.jpba.2007.05.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Revised: 05/07/2007] [Accepted: 05/19/2007] [Indexed: 10/23/2022]
Abstract
A capillary electrophoretic method has been developed for the enantioselective analysis of amisulpride in pharmaceutical formulations, using beta-cyclodextrin sulfate as the chiral selector. Several parameters, such as cyclodextrin type and concentration, buffer concentration and pH and capillary temperature were investigated for method optimisation. Baseline enantioseparation of the racemic compound was achieved in less than 10 min using a fused silica capillary (50 microm i.d. and 33.0, 8.5 cm, total and effective length, respectively), filled with a background electrolyte consisting of a 10mM citrate buffer at pH 3.5 supplemented with 0.22% (w/v) beta-cyclodextrin sulfate at 20 degrees C and applying a voltage of +15 kV. Formulation analysis was carried out after analyte extraction by methanol. The method was fully validated, with good results in terms of precision, selectivity, accuracy and amount of drug found with respect to the label claim. Thus, the method seems to be suitable for the enantiomeric analysis of amisulpride in pharmaceutical formulations.
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Affiliation(s)
- Alessandro Musenga
- Department of Pharmaceutical Sciences, University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy
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171
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Jiang C, Armstrong DW, Péter A, Fülöp F. Enantiomeric Separation of a Series of β‐Lactams Using Capillary Zone Electrophoresis. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070701360236] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- C. Jiang
- a Department of Chemistry and Biochemistry , University of Texas at Arlington , Arlington, Texas, USA
| | - D. W. Armstrong
- a Department of Chemistry and Biochemistry , University of Texas at Arlington , Arlington, Texas, USA
| | - A. Péter
- b Department of Inorganic and Analytical Chemistry , University of Szeged , Szeged, Hungary
| | - F. Fülöp
- c Institute of Pharmaceutical Chemistry University of Szeged , Szeged, Hungary
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172
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Jiang C, Armstrong DW, Lantz AW, Péter A, Tóth G. Enantiomeric Separation of Synthetic Amino Acids Using Capillary Zone Electrophoresis. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070701277018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- C. Jiang
- a Department of Chemistry and Biochemistry , University of Texas at Arlington , Arlington, Texas
| | - Daniel W. Armstrong
- a Department of Chemistry and Biochemistry , University of Texas at Arlington , Arlington, Texas
| | - A. W. Lantz
- b Department of Chemistry , Iowa State University , Ames, Iowa
| | - A. Péter
- c Department of Inorganic and Analytical Chemistry , University of Szeged , Szeged, Hungry
| | - G. Tóth
- d Institute of Biochemistry, Biological Research Center , Szeged, Hungry
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173
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Chu BL, Guo BY, Peng Z, Wang Z, Guo G, Lin JM. Studies on degradation of imazalil enantiomers in soil using capillary electrophoresis. J Sep Sci 2007; 30:923-9. [PMID: 17536738 DOI: 10.1002/jssc.200600447] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A scheme was demonstrated to elucidate the degradation behaviors of the two enantiomers of the fungicide imazalil in soil using cyclodextrin-modified capillary zone electrophoresis. The separation buffer was 50 mmol/L NaH2PO4, 5 mmol/L (NH4)H2PO4, and 5 mmol/L beta-cyclodextrin (pH 3.0). The limits of detection of this CE method were 0.24 and 0.26 microg/mL for (-)- and (+)-imazalil, respectively. Five different soil conditions were investigated in laboratory microcosms: under sunlight; in darkness; under UV irradiation; in sterilized soil; and in soil with wheat planted in it. Radiation, microorganisms, and uptake by wheat benefited the degradation of imazalil in this study. The half-lives (t1/2) of imazalil in soil under the above conditions were 20, 30.5, 11, 27.5, and 21.5 days, respectively. The degradation rate of imazalil in soil under the five different sets of conditions decreased in the order: UV irradiation > sunlight > soil with wheat planted in it > sterilized soil > soil kept in darkness. Imazalil in soil (pH 8.2, slightly alkaline) collected in the suburbs showed non-enantioselective degradation.
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Affiliation(s)
- Bao-Lin Chu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China
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174
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Abstract
Analyses of cytokinins are very important in both plant physiological and biomedical research as they are implicated in many biological processes. Reliable, sensitive, selective and inexpensive methods that are flexible and designed for automation are required for these analyses. This review addresses the advances made in the separation and determination of cytokinins by CE as well as the other applications of CE (i.e., determination of dissociation constants and complexation constants of cytokinins). The various CE modes used to separate the compounds and the quantification strategies are examined. Special attention is also focused on those aspects that improve on the sensitivity and/or selectivity, such as sample extraction and preconcentration, on-line preconcentration techniques (stacking), and/or specific detectors (e.g., MS). With the coupling to the preconcentration techniques and certain detection systems, numerous CE methods can potentially be adapted for the analysis of cytokinins in complex biological samples. Therefore, we would anticipate wider applications of CE methods in the near future for cytokinin analyses, which should facilitate a decrease in analysis cost and should help to improve analysis efficiency.
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Affiliation(s)
- Liya Ge
- Natural Sciences and Science Education Academic Group, Nanyang Technological University, Singapore
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175
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Viberg P, Spégel P, Carlstedt J, Jörntén-Karlsson M, Petersson P. Continuous full filling capillary electrochromatography: chromatographic performance and reproducibility. J Chromatogr A 2007; 1154:386-9. [PMID: 17418224 DOI: 10.1016/j.chroma.2007.02.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 02/14/2007] [Accepted: 02/20/2007] [Indexed: 11/22/2022]
Abstract
Continuous full filling capillary electrochromatography with nanoparticles as pseudostationary phase interfaced with electrospray ionisation mass spectrometric detection was used for reversed phase separations with very high separation efficiency. Several batches of nanoparticles were synthesised and their electrochromatographic performance were evaluated. Different parameters, such as repeatability, reproducibility, limit of detection, and peak asymmetry, were investigated yielding excellent results. The stability of the system over wide pH ranges and over time was found to be excellent. Very high separation efficiencies with over 1.1 million theoretical plates per metre were obtained. The limit of detection for the investigated dialkyl phthalates was approximately 1.0 micromol L(-1), corresponding to 3-5 fmol injected. After preparation, nanoparticle suspensions could be used without further treatment for at least an entire working day with maintained chromatographic qualities.
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Affiliation(s)
- Peter Viberg
- Analytical Chemistry, Centre for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
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176
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Ramstad T, Mills KA, Walker GA. Determination of the Enantiomeric Purity of a CNS Agent, Sumanirole, by Electrokinetic Chromatography. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070600716785] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Tore Ramstad
- a Department of Pharmaceutical Sciences , Pfizer Corp. , Kalamazoo, Michigan, USA
| | - Kent A. Mills
- a Department of Pharmaceutical Sciences , Pfizer Corp. , Kalamazoo, Michigan, USA
| | - Gustavus A. Walker
- a Department of Pharmaceutical Sciences , Pfizer Corp. , Kalamazoo, Michigan, USA
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177
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Yuan H, Thompson RA, Ellison DK. ENANTIOMERIC SEPARATION OF A DRUG SUBSTANCE USING CAPILLARY ELECTROPHORESIS WITH SULFATED-β-CYCLODEXTRIN. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120015887] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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178
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Stefan‐van Staden R, Nejem RM. Enantioselective, Potentiometric Membrane Electrodes Based on Cyclodextrins for the Assay ofL‐ andD‐2‐Hydroxyglutaric Acid. ANAL LETT 2007. [DOI: 10.1080/00032710500230830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
| | - R'afat M. Nejem
- a Department of Chemistry , University of Pretoria , Pretoria , South Africa
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179
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Castro-Puyana M, Lomsadze K, LCrego A, Marina ML, Chankvetadze B. Separation of enantiomers of deprenyl with various CDs in CE and the effect of enantiomer migration order on enantiomeric impurity determination of selegiline in active ingredients and tablets. Electrophoresis 2007; 28:388-94. [PMID: 17361461 DOI: 10.1002/elps.200600426] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Opposite affinity pattern of enantiomers of the antiparkinsonian chiral drug deprenyl (DEP) was observed towards various neutral and charged derivatives of -CD. The effect of the enantiomer migration order on the LOD of enantiomeric impurity of R-DEP (selegiline) was studied for the standard substances and in the tablets from three different suppliers. The influence of injection mode on the LOD of a minor enantiomeric impurity was also studied and the CE method was compared with the pharmacopoeial HPLC method using a commercially available chiral column Chiralcel OD-H. The optimized CE method was more suitable for low-level enantiomeric impurity determination in selegiline compared to the pharmacopoeial HPLC method.
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Affiliation(s)
- María Castro-Puyana
- Departamento de Química Analítica, Facultad de Química, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
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180
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Viberg P, Spégel P, Nilsson J, Petersson P, Jörntén-Karlsson M, Nilsson S. Reversed Phase Continuous Full Filling CEC–ESI–MS. Chromatographia 2007. [DOI: 10.1365/s10337-006-0165-7] [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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181
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Threeprom J. (S)-(+)-2-Octanol as a Chiral Oil Core for the Microemulsion Electrokinetic Chromatographic Separation of Chiral Basic Drugs. ANAL SCI 2007; 23:1071-5. [PMID: 17878580 DOI: 10.2116/analsci.23.1071] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The enantiomeric separation of basic drugs was successfully demonstrated by using a novel chiral microemulsion electrokinetic chromatography (MEEKC). An interesting finding was that the chiral oil core ((S)-(+)-2-octanol) within the microemulsion droplets appeared to play an important role in the chiral separation mechanism. In addition, the enantioselectivity of the analyte-selector complex could be influenced by methanol, through an interaction with the complex. The chiral resolution (R(s)) and partition coefficient were strongly influenced by the concentration of methanol, pH, the concentration of chiral oil and the concentration of a cosurfactant. Under the optimized microemulsion conditions, the baseline separation of (+/-)-ephedrine (R(s) = 2.7), and the partial separations of (+/-)-norephedrine (R(s) = 1.3), (+/-)-synephrine (R(s) = 1.4) and (+/-)-propranolol (R(s) = 1.3), could be achieved.
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Affiliation(s)
- Jirasak Threeprom
- Department of Chemistry, Faculty of Science, Mahasarakham University, Thailand.
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182
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Lee WS, Chan MF, Tam WM, Hung MY. The application of capillary electrophoresis for enantiomeric separation of N,N-dimethylamphetamine and its related analogs: Intelligence study on N,N-dimethylamphetamine samples in crystalline and tablet forms. Forensic Sci Int 2007; 165:71-7. [PMID: 16616443 DOI: 10.1016/j.forsciint.2006.03.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2005] [Revised: 02/23/2006] [Accepted: 03/03/2006] [Indexed: 10/24/2022]
Abstract
This paper reports a new capillary zone electrophoresis method for the simultaneous chiral determination of the enantiomers of N,N-dimethylamphetamine (DMA), methamphetamine (MA), ephedrine (E), pseudoephedrine (PE) and methylephedrine (Me-E). In this study, a number of electophoretic parameters were examined and optimized including the choice of chiral selectors, the use of short-chain tetraalkylammonium cations, the effect of chiral selector concentration, buffer concentration, applied voltage and capillary temperature. Heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CD) and tetrabutylammonium (TBA) being the best chiral selector and buffer cation, respectively, the optimized electrophoretic conditions were found to be: 20 mM DM-beta-CD, 50 mM TBAPO(4) at pH 2.5, applied voltage at 30 kV and temperature at 25 degrees C. Under the optimized conditions, all analytes were well separated with resolution factors between 3.3 and 24.0 achieved. Using phentermine as an internal standard, the intra-day (n=8) precisions for the relative migration times and peak areas of all analytes were below 1.09%, while the inter-day precisions (n=12, 6 days) for the relative migration times and peak areas of all analytes were under 3.77%. This method has been applied to the measurement of the enantiomeric purities of the seized DMA samples. The result of the measurement could provide important clues about the possible synthetic pathways of these samples.
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Affiliation(s)
- Wing-Sze Lee
- Forensic Science Division, Government Laboratory, Homantin Government Offices, Hong Kong, China.
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183
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Rudzińska E, Poliwoda A, Berlicki Ł, Mucha A, Dzygiel P, Wieczorek PP, Kafarski P. Enantiodifferentiation of N-benzyloxycarbonylaminophosphonic and phosphinic acids and their esters using cyclodextrins by means of capillary electrophoresis. J Chromatogr A 2007; 1138:284-90. [PMID: 17097095 DOI: 10.1016/j.chroma.2006.10.065] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Revised: 10/25/2006] [Accepted: 10/26/2006] [Indexed: 11/22/2022]
Abstract
Capillary electrophoresis was successfully applied for separation of the enantiomers of N-benzyloxycarbonyl-alpha-aminophosphonic and alpha-aminophosphinic acids as well as their ethyl and phenyl monoesters with the use of a range of commercially available cyclodextrins (alpha, beta and hydroxypropyl-gamma-cyclodextrins) as chiral selectors. The dependence of effectiveness of separation on type and concentration of these chiral selectors as well as on pH of background electrolyte was examined in some detail.
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Affiliation(s)
- Ewa Rudzińska
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wrocław University of Technology, Wybrzeze Wyspiańskiego 27, 50-370 Wrocław, Poland
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184
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Wang J, Yuan Q, Evans DG, Yang L, Zheng G, Sun W. Enantioselective separation of phenylglycidates by capillary electrophoresis employing sulfated beta-cyclodextrin as chiral selector. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 850:560-3. [PMID: 17257909 DOI: 10.1016/j.jchromb.2006.12.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2005] [Revised: 11/16/2006] [Accepted: 12/04/2006] [Indexed: 10/23/2022]
Abstract
A capillary electrophoresis (CE) method for the enantioseparation of phenylglycidates has been developed. Successful enantioseparation was achieved using sulfated beta-cyclodextrin as chiral selector in a phosphate buffer. The effects of varying pH, sulfated beta-cyclodextrin concentration and electrophoresis voltage were systematically investigated and the optimized separation conditions were thus obtained. When the migration time was set at the threshold value, it was found that the best enantioseparation was obtained at 10 kV with 3% (w/v) sulfated beta-cyclodextrin at pH 6.5. A range of substituted phenylglycidates were successfully separated using the method and the results shown to be superior to those obtained using gas chromatography (GC).
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Affiliation(s)
- Jianjun Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, PR China
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185
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Petr J, Maier V, Horáková J, Sevcík J. Simultaneous contactless conductivity detection and UV detection for the study of separation of tamsulosin enantiomers in discontinuous electrolyte systems by CE. Electrophoresis 2006; 27:4735-45. [PMID: 17080485 DOI: 10.1002/elps.200600063] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This work shows the potential of using discontinuous electrolyte systems for the separation of tamsulosin enantiomers by CE. Sulfated beta-cyclodextrin was used as a chiral selector. In acidic electrolytes, sulfated beta-cyclodextrin migrates as an anion and the analyte (tamsulosin) migrates as a cation. Due to this, four experimental arrangements were proposed. These arrangements differ in composition of electrolytes in the inlet compartment, in the capillary and in the outlet compartment. The separation of tamsulosin enantiomers in acetate buffers with sodium and Tris counterions was studied. Simultaneous contactless conductivity detection and UV detection were used for the study of the separation mechanism in these systems. Mobilities of sulfated beta-cyclodextrin were used for the calculation of the time when the analyte migrates through the BGE zone with the selector. The simulation program Simul 4.0 was used for the calculations of the concentration profiles of the electrolyte components dependent on the time of the separation. The mechanism of enantioseparation in these arrangements was suggested.
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Affiliation(s)
- Jan Petr
- Department of Analytical Chemistry, Palacký University, Olomouc, Czech Republic.
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186
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Zhou S, Ouyang J, Baeyens WRG, Zhao H, Yang Y. Chiral separation of four fluoroquinolone compounds using capillary electrophoresis with hydroxypropyl-β-cyclodextrin as chiral selector. J Chromatogr A 2006; 1130:296-301. [PMID: 16774760 DOI: 10.1016/j.chroma.2006.05.055] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2006] [Revised: 05/17/2006] [Accepted: 05/19/2006] [Indexed: 11/30/2022]
Abstract
A capillary zone electrophoresis (CZE) investigation on the enantiomeric separation of lomefloxacin, gatifloxacin, pazufloxacin and ofloxacin was undertaken. Resolution of the enantiomers was achieved using hydroxypropyl-beta-cyclodextrin (HP-beta-CD) as the chiral selector. Parameters influencing separation include cyclodextrin concentration, separational potential, pH and organic additive are discussed. A buffer consisting of 70 mM phosphate and 40 mM HP-beta-CD at pH 3.96 was found to be highly efficient for the separation of lomefloxacin, at pH 3.90 for gatifloxacin, at pH 5.04 for pazufloxacin and at pH 2.16 for ofloxacin. To the best of our knowledge, this is the first report on the enantiomeric resolution of lomefloxacin and gatifloxacin applying CE.
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Affiliation(s)
- Shanshan Zhou
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
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187
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Wang ZY, Xu XX, Hu ZD, Kang JW. Sensitive Method for Enantioseparation of Rivastigmine with Highly Sulfated Cyclodextrin as Chiral Selector by Capillary Electrophoresis. CHINESE J CHEM 2006. [DOI: 10.1002/cjoc.200690258] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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188
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Ramstad T. Enantiomeric purity methods for three pharmaceutical compounds by electrokinetic capillary chromatography utilizing highly sulfated-γ-cyclodextrin as the chiral selector. J Chromatogr A 2006; 1127:286-94. [PMID: 16806246 DOI: 10.1016/j.chroma.2006.06.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Revised: 05/29/2006] [Accepted: 06/06/2006] [Indexed: 11/24/2022]
Abstract
Methods for enantiomeric purity by electrokinetic chromatography were developed and validated for three pharmaceutical compounds, each utilizing highly sulfated-gamma-cyclodextrin (HS-gamma-CD) as the chiral recognition agent. Two of the compounds are weak bases, hence charged at low pH, and the third is a quaternary nitrogen compound, charged at all pH. In each instance quantification was via an authentic reference standard with addition of an internal standard. Separation was on a 61 cm x 50 microm untreated capillary under reverse polarity with a background electrolyte of 5% HS-gamma-CD in pH 2.50 lithium phosphate buffer. Each method was validated with respect to the usual validation parameters, notably recovery and precision, yielding results, including limits of detection and quantitation, that allow reporting the minor enantiomer to 0.1% and less. In applying the methods, all batches of bulk drug tested were shown to be of enantiomeric purity > or =99.9%.
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Affiliation(s)
- Tore Ramstad
- Pharmaceutical Sciences, Pfizer Corp., Kalamazoo, MI 49001, USA.
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189
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Lin CE, Cheng HT, Fang IJ, Liu YC, Kuo CM, Lin WY, Lin CH. Strategies for enantioseparations of catecholamines and structurally related compounds by capillary zone electrophoresis using sulfated β-cyclodextrins as chiral selectors. Electrophoresis 2006; 27:3443-51. [PMID: 16944458 DOI: 10.1002/elps.200500658] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Strategies for simultaneous enantioseparations of three catecholamines (DL-norepinephrine, DL-epinephrine, and DL-isoproterenol) and three structurally related compounds (DL-octopamine, DL-synephrine, and DL-norephedrine) by CZE using sulfated beta-CDs as chiral selectors were investigated. Four different separation modes were attempted: (I) using randomly sulfate-substituted beta-CD (MI-S-beta-CD) at relatively low concentrations in a high-concentration phosphate buffer at low pH in the normal polarity mode, (II) using MI-S-beta-CD at high concentrations at low pH in the reversed polarity mode, (III) using MI-S-beta-CD at moderately high concentrations in a phosphate buffer at neutral pH in the normal polarity mode, and (IV) using the single isomer heptakis(2,3-dihydroxy-6-O-sulfo)-beta-CD (SI-S-beta-CD) at low to moderately high concentrations in a high-concentration BGE at low pH in the normal polarity mode. Among them, enantioseparation of these cationic solutes was best achieved under the conditions of mode (II). In mode (II) and mode (III), temperature is an important factor affecting the enantioresolution of norepinephrine. In mode (I) and mode (IV), the use of a high-concentration BGE (150-200 mM) is crucial for effective enantioseparation of these cationic solutes with sulfated beta-CDs. Comparative studies of enantioseparations of these cationic solutes with MI-S-beta-CD and SI-S-beta-CD reveal that the sulfate substituents of MI-S-beta-CD located at the C(2)- position interact strongly with the diol moiety of catecholamines.
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Affiliation(s)
- Ching-Erh Lin
- Department of Chemistry, National Taiwan University, Taipei, Taiwan.
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190
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Merino F, Rubio S, Pérez-Bendito D. Supramolecular systems-based extraction-separation techniques coupled to mass spectrometry. J Sep Sci 2006; 28:1613-27. [PMID: 16224955 DOI: 10.1002/jssc.200500161] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The combination of supramolecular chemistry and MS has not only been fruitful in the field of gas-phase fundamental studies of host-guest complexes and supramolecular assemblies. Mass spectrometric analysis has also benefited from the ability of supramolecular systems to behave as pseudophases in which solutes partition from the bulk solvent phase. Supramolecular systems-based extraction and concentration schemes and separation techniques have been widely used in different fields of analytical chemistry and are ideally suited for coupling with MS. This review describes the present status of the application of supramolecular chemistry in mass spectrometric analysis and includes topics such as the use of coacervative liquid-liquid extraction and hemimicelle/admicelle-based SPE of organic compounds prior to chromatography and electrophoresis. It also discusses the recent advances in enantioselective analysis using CD in electrophoresis- and chromatography-MS. The potential and analytical challenges of these approaches in environmental and bioanalytical chemistry, where one can expect significant developments in the future, are outlined.
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Affiliation(s)
- Francisco Merino
- Department of Analytical Chemistry, Campus de Rabanales, Edificio Anexo Marie Curie, University of Córdoba, Córdoba, Spain
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191
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Bonato PS, Jabor VAP, Paias FO, Lanchote VL. CHIRAL CAPILLARY ELECTROPHORETIC SEPARATION OF SELECTED DRUGS AND METABOLITES USING SULFATED β-CYCLODEXTRIN. J LIQ CHROMATOGR R T 2006. [DOI: 10.1081/jlc-100103435] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- P. S. Bonato
- a Universidade de São Paulo , Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Avenida do Café s/n, Ribeirão Preto, CEP 14040-903, Brazil
| | - V. A. P. Jabor
- a Universidade de São Paulo , Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Avenida do Café s/n, Ribeirão Preto, CEP 14040-903, Brazil
| | - F. O. Paias
- a Universidade de São Paulo , Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Avenida do Café s/n, Ribeirão Preto, CEP 14040-903, Brazil
| | - V. L. Lanchote
- a Universidade de São Paulo , Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Avenida do Café s/n, Ribeirão Preto, CEP 14040-903, Brazil
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192
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Ramstad T, Johnson RL. Method for enantiomeric purity of a quinuclidine candidate drug by capillary electrophoresis. J Sep Sci 2006; 29:2056-64. [PMID: 17017019 DOI: 10.1002/jssc.200600069] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A chiral procedure based on EKC was developed and validated for determination of the enantiomeric purity of PHA-543613, a drug candidate that was under development for treatment of the cognitive deficits of Alzheimer's disease and schizophrenia. Separation of enantiomers is accomplished via differential, enantiospecific complexation with a single-isomer, precisely sulfated beta-CD and heptakis-6-sulfato-beta-CD (HpS-beta-CD). Both neutral and sulfated CDs were screened before selecting HpS-beta-CD as the chiral selector. The separation is conducted in a 61 cm x 50 microm uncoated fused silica capillary with 25 mM HpS-beta-CD in pH 2.50, 25 mM lithium phosphate as the separation buffer with detection at 220 nm. Application of reverse polarity at -30 kV results in an elution time of about 12 min for PHA-543613 and 13 min for the undesired S-enantiomer. Quantification is versus an authentic reference S-enantiomer as an external standard in combination with an internal standard. The procedure was validated over the range 0.1-2.0% w/w. The detection limit is 0.01-0.02%. The amount of distomer intrinsic to the drug substance is about 0.1% or less. The developed method was used to generate stability data on multiple lots: in one case for up to 3 years.
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MESH Headings
- Bridged Bicyclo Compounds, Heterocyclic/chemistry
- Bridged Bicyclo Compounds, Heterocyclic/isolation & purification
- Bridged Bicyclo Compounds, Heterocyclic/standards
- Chromatography, High Pressure Liquid/methods
- Chromatography, Micellar Electrokinetic Capillary/methods
- Chromatography, Micellar Electrokinetic Capillary/standards
- Chromatography, Micellar Electrokinetic Capillary/statistics & numerical data
- Electrophoresis, Capillary/methods
- Electrophoresis, Capillary/standards
- Electrophoresis, Capillary/statistics & numerical data
- Nicotinic Agonists/chemistry
- Nicotinic Agonists/isolation & purification
- Nicotinic Agonists/standards
- Nootropic Agents/chemistry
- Nootropic Agents/isolation & purification
- Nootropic Agents/standards
- Quinuclidines/chemistry
- Quinuclidines/isolation & purification
- Quinuclidines/standards
- Reference Standards
- Stereoisomerism
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Affiliation(s)
- Tore Ramstad
- Pharmaceutical Sciences, Pfizer Corporation, Kalamazoo, MI 49001, USA.
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193
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Eder AR, Chen JS, Arriaga EA. Separation of doxorubicin and doxorubicinol by cyclodextrin-modified micellar electrokinetic capillary chromatography. Electrophoresis 2006; 27:3263-70. [PMID: 16915573 DOI: 10.1002/elps.200600025] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Doxorubicinol (DOXol) is a human metabolite of the chemotherapy agent doxorubicin (DOX), and is associated with dose-dependent cardiotoxicity and decreased drug efficacy. Due to the structural similarities and equal molecular charges of DOXol and DOX, their electrophoretic separation is commonly ineffective. A method for separating and detecting DOX and DOXol, as well as two DOXol enantiomers, was established using cyclodextrin-modified micellar electrokinetic capillary chromatography with laser-induced fluorescence detection. Differential DOXol production was detected in a DOX-sensitive and resistant pair of cell lines, with a 0.08 +/- 0.01 fmol limit of detection.
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Affiliation(s)
- Angela R Eder
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
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194
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Weng X, Bi H, Liu B, Kong J. On-chip chiral separation based on bovine serum albumin-conjugated carbon nanotubes as stationary phase in a microchannel. Electrophoresis 2006; 27:3129-35. [PMID: 16807934 DOI: 10.1002/elps.200500840] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A novel method of chiral separation based on protein-stationary phase immobilized in a poly(methyl methacrylate) microfluidic chip was developed. BSA conjugated with the shortened carboxylic single-walled carbon nanotubes (SWNTs) was employed as the chiral selector. Successful separation of tryptophan enantiomers was achieved in less than 70 s with a resolution factor of 1.35 utilizing a separation length of 32 mm. This is the first example of chiral separation based on SWNTs-BSA conjugates as stationary phase immobilized in microchip channel. The stability of the stationary phase in the channel was examined by microchip electrophoresis with laser-induced fluorescence detection. Factors that influenced the chiral separation resolution were examined. Under the optimized conditions, the proposed modified chip revealed adequate repeatability concerning run-to-run. These results show that the use of SWNTs-BSA conjugates within microfluidic channels hold great promise for a variety of analytical schemes.
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Affiliation(s)
- Xuexiang Weng
- Department of Chemistry, Fudan University, Shanghai 200433, P. R. China
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195
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Gübitz G, Schmid MG. Chiral separation principles in chromatographic and electromigration techniques. Mol Biotechnol 2006; 32:159-80. [PMID: 16444017 DOI: 10.1385/mb:32:2:159] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Almost half of the drugs in use today are chiral. It is well established that the pharmacological activity is mostly restricted to one of the enantiomers (eutomer). There can be qualitative and quantitative differences in the activity of the enantiomers. In many cases, the inactive enantiomer (distomer) shows unwanted side effects or even toxic effects. Even if the side effects are not that drastic, the distomer has to be metabolized and this represents an unnecessary burden for the organism. Therefore, the development of methods for the separation of enantiomers, both on analytical and preparative scale, has become increasingly important. Chromatographic techniques such as thin layer chromatography (TLC), gas chromatography (GC), supercritical fluid chromatography (SFC), and above all high-performance liquid chromatography (HPLC) have been used for enantiomer separation for about two decades. More recently, electromigration techniques, such as capillary electrophoresis and capillary electrochromatography, have been shown to be powerful alternatives to chromatographic methods. This review gives a short overview of different chiral separation principles and their application. Several new developments are discussed.
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Affiliation(s)
- Gerald Gübitz
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Chemistry, Karl-Franzens University, Universitätsplatz 1, A-8010 Graz, Austria
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196
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Matthijs N, Maftouh M, Vander Heyden Y. Chiral separation strategy in polar organic solvent chromatography and performance comparison with normal-phase liquid and supercritical-fluid chromatography. J Sep Sci 2006; 29:1353-62. [PMID: 16894779 DOI: 10.1002/jssc.200500515] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A strategy, including a rapid screening and several optimisation steps, for the separation of chiral molecules of pharmaceutical interest by polar organic solvent chromatography (POSC), using four polysaccharide-based stationary phases, is proposed and compared with previously reported strategies in normal-phase (NPLC) and supercritical fluid chromatography (SFC). In a first part of this paper, different examples demonstrate the effectiveness of the POSC strategy for fast method development. Optimisation is based on the use of experimental design to map the experimental domain in an efficient way. In the second part, the best screening results, obtained after performance of earlier defined chromatographic screening strategies in NPLC and SFC, are compared to those obtained in POSC. The three techniques show complementary separation results and allowed baseline separation of 23 of 25 compounds. POSC is found to be a very interesting separation mode compared to NPLC, because of the many fast (< 10 min) baseline separations obtained.
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Affiliation(s)
- Nele Matthijs
- Dept. Analytical Chemistry and Pharmaceutical Technology, Pharmaceutical Institute, Vrije Universiteit Brussel, Brussels, Belgium
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197
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Van Eeckhaut A, Michotte Y. Chiral separations by capillary electrophoresis: Recent developments and applications. Electrophoresis 2006; 27:2880-95. [PMID: 16688697 DOI: 10.1002/elps.200500375] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This paper provides an overview of the different classes of chiral selectors that are used in CE. The main properties of every class are described, together with the mechanism of enantioseparation. Newly introduced selectors are also discussed. Pharmaceutical and biomedical applications published from January 2004 till March 2005 are summarized.
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Affiliation(s)
- Ann Van Eeckhaut
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Pharmaceutical Institute, Vrije Universiteit Brussel, Brussels, Belgium
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198
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Antczak A, Ramstad T, Johnson R. A CD-MEKC Method Utilizing a Neutral Surfactant for Enantiomeric Purity Determination of an Oxazolidinone Drug Candidate. Chromatographia 2006. [DOI: 10.1365/s10337-006-0828-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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199
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Liu H, Yu A, Liu F, Shi Y, Han L, Chen Y. Chiral separation of cefadroxil by capillary electrochromatography. J Pharm Biomed Anal 2006; 41:1376-9. [PMID: 16600557 DOI: 10.1016/j.jpba.2006.02.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 02/09/2006] [Accepted: 02/15/2006] [Indexed: 10/24/2022]
Abstract
In this paper, the chiral separation of cefadroxil was studied by capillary electrochromatography. Monolithic capillary column was prepared for the separation of cefadroxil enantiomers. The optimum buffer contained 28.5 mmol/L sodium acetate, 0.95% (v/v) acetic acid, 19 mmol/L beta-cyclodextrin (beta-CD) and 5% (v/v) isopropanol in formamide solution (pH 7.0), with the running voltage of 12 kV, the UV detector wavelength of 254 nm, the sample injected time of 8s and the temperature of 25 degrees C. Under these conditions, the column efficiency of cefadroxil enantiomers were N1=5324 and N2=23,768 with a selectivity factor (alpha) of 1.056 and resolution (Rs) of 0.978. The effect of buffer pH value, beta-CD concentration, organic modifier (isopropanol) concentration and voltage was also investigated for the separation by CEC.
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Affiliation(s)
- Haixing Liu
- Department of Chemistry, Weifang University, Weifang 261061, China.
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200
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Abstract
Chiral separation of cetirizine, a second-generation H(1)-antagonist, was studied by CD-mediated CE. Several parameters, including pH, CD type, buffer concentration, type of co-ion, applied voltage and temperature, were investigated. The best conditions for chiral separation were obtained using a 75 mM triethanolamine-phosphate buffer (pH 2.5) containing 0.4 mg/mL heptakis(2,3-diacetyl-6-sulfato)-beta-CD and 10% ACN. Online UV detection was performed at 214 nm, a voltage of 20 kV was applied and the capillary was temperature controlled at 25 degrees C by liquid cooling. Hydrodynamic injection was performed for 1 s. The method was validated for the quantification of levocetirizine in tablets and for enantiomeric purity testing of the drug substance. Selectivity, linearity, LOD and LOQ, precision and accuracy were evaluated for both methods. The amount of levocetirizine dihydrochloride in the commercially available tablets was quantified and was found to be within the specification limits of the claimed amount (5 mg). The amount of distomer in levocetirizine drug substance was found to be 0.87 +/- 0.09% w/w, which is in agreement with the certificate of analysis supplied by the company.
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Affiliation(s)
- Ann Van Eeckhaut
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Pharmaceutical Institute, Vrije Universiteit Brussel, Brussels, Belgium
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