title: Separation of N-derivatized di- and tri-peptide stereoisomers by micro-liquid chromatography using a quinidine-based monolithic column - Analysis of l-carnosine in dietary supplements.
abstract: In the present study, a new analytical methodology was developed enabling the enantiomeric determination of N-derivatized di- and tri-peptides in dietary supplements using chiral micro-LC on a monolithic column consisting of poly(O-9-[2-(methacryloyloxy)-ethylcarbamoyl]-10,11-dihydroquinidine-co-2-hydroxyethyl methacrylate-co-ethylene dimethacrylate) (poly(MQD-co-HEMA-co-EDMA)). After optimization of the mobile phase conditions, a baseline resolution of the stereoisomers of 24 out of 53 N-derivatized di- and tri-peptides was obtained. 3,5-Dinitrobenzoyl- and 3,5-dichlorobenzoyl-peptide stereoisomers were separated with exceptionally high selectivity and resolution. The monolithic column was then applied to the quantitative analysis of l-carnosine and its enantiomeric impurity in three different commercial dietary supplements. Method validation demonstrated satisfactory results in terms of linearity, precision, selectivity, accuracy and limits of detection and quantification. The determined amounts of l-carnosine in commercial formulations were in agreement with the labeled content for all analyzed samples, and the enantiomeric impurity was found to be below the limit of detection (LOD), showing the potential of the poly(MQD-co-HEMA-co-EDMA) monolithic column as a reliable tool for the quality control of l-carnosine in dietary supplements by micro-LC.
authors.affiliation: Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China; Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology, Environmental Sciences and Chemistry, University of Alcalá, Ctra. Madrid-Barcelona, Km. 33.600, Alcalá de Henares, 28871 Madrid, Spain.
authors.forename: Qiqin
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology, Environmental Sciences and Chemistry, University of Alcalá, Ctra. Madrid-Barcelona, Km. 33.600, Alcalá de Henares, 28871 Madrid, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Sánchez-López
authors.affiliation: Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Han
authors.affiliation: Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China.
authors.forename: Huihui
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China.
authors.forename: Peijie
authors.initials: P
authors.lastname: Zhu
authors.affiliation: Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China; Laboratory of Analytical Pharmaceutical Chemistry, Department of Pharmaceutical Sciences, University of Liege, CHU B36, B-4000 Liege, Belgium.
authors.forename: Jacques
authors.initials: J
authors.lastname: Crommen
authors.affiliation: Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology, Environmental Sciences and Chemistry, University of Alcalá, Ctra. Madrid-Barcelona, Km. 33.600, Alcalá de Henares, 28871 Madrid, Spain. Electronic address: mluisa.marina@uah.es.
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Marina
authors.affiliation: Department of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine & New Drug Research, Jinan University, Guangzhou 510632, China. Electronic address: jzjjackson@hotmail.com.
authors.forename: Zhengjin
authors.initials: Z
authors.lastname: Jiang
mesh_terms: D002336:Carnosine / Q000032:analysis* / Q000302:isolation & purification; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002853:Chromatography, Liquid; D019587:Dietary Supplements / Q000032:analysis*; D008689:Methacrylates / Q000737:chemistry; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification*; D011802:Quinidine / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D008689:Methacrylates; D010455:Peptides; C005044:hydroxyethyl methacrylate; C004919:ethylene dimethacrylate; D002336:Carnosine; D011802:Quinidine
keywords: Carnosine; Dietary supplements; Enantioseparation; Quinidine-based monolithic column; Small peptides