title: Fast and quantitative analysis of branched-chain amino acids in biological samples using a pillar array column.
abstract: In this study, a fast and quantitative determination method for branched-chain amino acids (BCAAs), namely leucine, isoleucine, and valine, was developed using a pillar array column. A pillar array column with low-dispersion turns was fabricated on a 20 × 20-mm(2) microchip using multistep ultraviolet photolithography and deep reactive ion etching. The BCAAs were fluorescently labeled with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F), followed by reversed-phase separation on the pillar array column. The NBD derivatives of the three BCAAs and an internal standard (6-aminocaproic acid) were separated in 100 s. The calibration curves for the NBD-BCAAs had good linearity in the range of 0.4-20 μM, using an internal standard. The intra- and interday precisions were found to be in the ranges of 1.42-3.80 and 2.74-6.97%, respectively. The accuracies for the NBD-BCAA were from 90.2 to 99.1%. The method was used for the analysis of sports drink and human plasma samples. The concentrations of BCAAs determined by the developed method showed good agreements with those determined using a conventional high-performance liquid chromatography system. As BCAAs are important biomarkers of some diseases, these results showed that the developed method could be a potential diagnostic tool in clinical research.
authors.affiliation: Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan.
authors.forename: Yanting
authors.initials: Y
authors.lastname: Song
authors.forename: Katsuya
authors.initials: K
authors.lastname: Takatsuki
authors.forename: Muneki
authors.initials: M
authors.lastname: Isokawa
authors.forename: Tetsushi
authors.initials: T
authors.lastname: Sekiguchi
authors.forename: Jun
authors.initials: J
authors.lastname: Mizuno
authors.forename: Takashi
authors.initials: T
authors.lastname: Funatsu
authors.forename: Shuichi
authors.initials: S
authors.lastname: Shoji
authors.forename: Makoto
authors.initials: M
authors.lastname: Tsunoda
mesh_terms: D000597:Amino Acids, Branched-Chain / Q000097:blood*; D001628:Beverages / Q000032:analysis; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D010069:Oxadiazoles / Q000737:chemistry
chemical_list: D000597:Amino Acids, Branched-Chain; D010069:Oxadiazoles