.lc / Esi-ms ~ N In The Analysis Of Several Drugs And Metabolites

In this paper, the liquid chromatography-electrospray ion trap mass spectrometry had been applied successfully to the metabolites identification, structural elucidation and medicine quality control.1. The experiment conditions of the microbial model for gliclazide biotransformation was optimized by liquid chromatography-electrospray ion trap mass spectrometric method. Three major metabolites were isolated by chromatographic method and identified by NMR and ESI-MSⁿ. The mass spectometric characteristics of gliclazide and its metabolites were summarized. The metbolites in the microbial model and human were investigated. 8 metabolites were found in microbial model and 5 mono-hydroxylated metabolits of them were also found in human metabolites. It was indicated that microbial models have the abilities to minic human metabolism of drug and could partly replace the mammals in drug metabolism study.2. The fragmentation behaviors of 7 compounds containing carbamate group were investigated by collision induced dissociation. Both electrospray-ion trap mass spectrometry and electrospray-Fourier transform ion cyclotron resonance mass spectrometry were used to analyze the compounds. The samples were infused into the ion source with a syringe pump and the experiments were carried out in the positive ion mode. The most abundant fragment ion in MS² spectrum was [M + H - 44]⁺ ion. The accurate masses of the fragment ions proved that the loss of 44 u corresponded to the neutral loss of CO₂. A mechanism for the loss of CO₂ has been proposed. It was suggested that [M + H - 44]⁺ ion could be used as "diagnostic ion" of the structural elucidation of compounds containing carbamate group.3. A liquid chromatography-electrospray ion trap mass spectrometric method was develop for the identification of phenformin and glyburide illegally added in traditional Chinese medicine preparations and test some formulations. The organic extract of traditional Chinese medicine preparations was analyzed and the compounds illegally added in traditional Chinese medicine preparations were identified according to the chromatographic behavior and mass spectral data by...