title: Rapid and sensitive determination of free thiols by capillary zone electrophoresis with near-infrared laser-induced fluorescence detection using a new BODIPY-based probe as labeling reagent.
abstract: A CZE with near-infrared (NIR) LIF detection method has been developed for the analysis of six low molecular weight thiols including glutathione, homocysteine, cysteine, γ-glutamylcysteine, cysteinylglycine, and N-acetylcysteine. For this purpose, a new NIR fluorescent probe, 1,7-dimethyl-3,5-distyryl-8-phenyl-(4'-iodoacetamido)difluoroboradiaza-s-indacene was utilized as the labeling reagent, whose excitation wavelength matches the commercially available NIR laser line of 635 nm. The optimum procedure included a derivatization step of the free thiols at 45°C for 25 min and CZE analysis conducted within 14 min in the running buffer containing 16 mmol/L pH 7.0 sodium citrate and 60% v/v ACN. The LODs (S/N = 3) ranged from 0.11 nmol/L for N-acetylcysteine to 0.31 nmol/L for γ-glutamylcysteine, which are better than or comparable to those reported with other derivatization-based CE-LIF methods. As the first trial of NIR CE-LIF method for thiol determination, the practical application of the proposed method has been validated by detecting thiols in cucumber and tomato samples with recoveries of 96.5-104.3%.
authors: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, P. R. China.
authors: Li-Yun
authors: LY
authors: Zhang
authors: Feng-Qin
authors: FQ
authors: Tu
authors: Xiao-Feng
authors: XF
authors: Guo
authors: Hong
authors: H
authors: Wang
authors: Peng
authors: P
authors: Wang
authors: Hua-Shan
authors: HS
authors: Zhang
mesh_terms: D000603:Amino Acids, Sulfur / Q000032:analysis / Q000737:chemistry; D001896:Boron Compounds / Q000737:chemistry*; D004355:Drug Stability; D019075:Electrophoresis, Capillary / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry*; D005978:Glutathione / Q000032:analysis / Q000737:chemistry; D057230:Limit of Detection; D016014:Linear Models; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000032:analysis* / Q000737:chemistry
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D000603:Amino Acids, Sulfur; D001896:Boron Compounds; D005456:Fluorescent Dyes; D013438:Sulfhydryl Compounds; D005978:Glutathione
keywords: 1,7-Dimethyl-3,5-distyryl-8-phenyl-(4'-iodoacetamido)difluoroboradiaza-s-indacene; Capillary electrophoresis; Near-infrared laser-induced fluorescence; Thiols