Abstract

A sensitive and reliable method for the determination of γ-aminobutyric acid (GABA), a major inhibitory neurotransmitter, in human plasma and cerebrospinal fluid (CSF) has been developed. The method is based on capillary liquid chromatography (LC)/tandem mass spectrometry (MS/MS) using deuterium-labeled GABA (γ-aminobutyric acid-2,2-D 2, GABA-d 2) as internal standard. Pre-column derivatization with 7-fluoro-4-nitrobenzoxadiazole (NBD-F) was deployed, allowing both effective in-line pre-concentration and sensitive tandem MS detection of the analyte. An extraction column (10 mm × 0.25 mm, 7 μm, C 18) was used for preconcentrating and stacking the sample. Separation was carried out on an analytical column (50 mm × 0.25 mm, 5 μm, C 18). Characteristic precursor-to-product ion transitions, m/ z 267 → 249 (for NBD-GABA) and m/ z 269 → 251 (for NBD-GABA-d 2) were monitered for the quantification. A linear calibration curve from 10 to 250 ng/mL GABA with an r 2 value of 0.9994 was obtained. Detection limit was estimated to be 5.00 ng/mL GABA (S/N = 3). Human plasma and CSF samples were analyzed. The concentrations of GABA were found to be 98.6 ± 33.9 ng/mL (mean ± S.D., n = 12), and 44.3 ± 10.0 ng/mL ( n = 6) in plasma and CSF, respectively.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.