A chiral GC–MS method for analysis of secondary amino acids after heptaluorobutyl chloroformate & methylamine derivatization

0539439 - BC 2022 RIV AT eng J - Journal Article
Opekar, Stanislav - Zahradníčková, Helena - Vodrážka, Petr - Řimnáčová, Lucie - Šimek, Petr - Moos, Martin
A chiral GC–MS method for analysis of secondary amino acids after heptaluorobutyl chloroformate & methylamine derivatization.
Amino Acids. Roč. 53, č. 3 (2021), s. 347-358. ISSN 0939-4451. E-ISSN 1438-2199
R&D Projects: GA ČR(CZ) GA17-22276S
Institutional support: RVO:60077344
Keywords : imino acids * secondary amino acids * enantiomeric separation
OECD category: Analytical chemistry
Impact factor: 3.789, year: 2021
Method of publishing: Limited access
https://link.springer.com/content/pdf/10.1007/s00726-021-02949-1.pdf

L-amino acids (L-AAs) play diferent important roles in the physiology of all living organisms. Their chiral counterparts, D-amino acids (D-AAs) are increasingly being recognized as essential molecules in many biological systems. Secondary amino acids with cyclic structures, such as prolines, exhibit conformational rigidity and thus unique properties in the structural and protein folding. Despite their widespread occurrence, much less attention was paid to their chiral analysis, particularly when the minor, typically D-enantiomer, is present in low amounts in a complex biological matrix. In this paper, a cost-efective, chiral GC–MS method is described for capillary Chirasil-L-Val separation of eight cyclic secondary amino acid enantiomers with four-, ive-, and six-membered rings, involving azetidine-2-carboxylic acid, pipecolic acid, nipecotic acid, proline, isomeric cis/trans 3-hydroxy, 4-hydroxyproline, and cis/trans-5-hydroxy-L-pipecolic acid in the excess of its enantiomeric antipode. The sample preparation involves in-situ derivatization with heptaluorobutyl chloroformate, simultaneous liquid–liquid micro-extraction into isooctane followed by amidation of the arising low-polar derivatives with methylamine, an evaporation step, re-dissolution, and inal GC–MS analysis. The developed method was used for analyses of human bioluids, biologically active peptides containing chiral proline constituents, and collagen.
Permanent Link: http://hdl.handle.net/11104/0326383