Quantification of neurotransmitters in mouse brain tissue by using liquid chromatography coupled electrospray tandem mass spectrometry

A simple and rapid liquid chromatography tandem mass spectrometry method has been developed for the determination of bh4,da,5-ht,ne,ep,glu,and gaba in mouse brain using epsilon-acetamidocaproic acid and isotopically labeled neurotransmitters as internal standards. proteins in the samples were precipitated by adding acetonitrile,and then the supernatants were separated by a sepax polar-imidazole (2.1 mm × 100 mm,i.d.,3 m) column by adding a mixture of 10 mm ammonium formate in acetonitrile/water (75: 25,v/v,300 l/min) for bh4 and da. to assay 5-ht,ne,ep,glu,and gaba; a luna 3 c18 (3.0 mm × 150 mm,i.d.,3 m) column was used by adding a mixture of 1% formic acid in acetonitrile/water (20: 80,v/v,350 l/min). the total chromatographic run time was 5.5 min. the method was validated for the analysis of samples. the calibration curve was linear between 10 and 2000 ng/g for bh4 r 2 = 0.995,10 and 5000 ng/g for da r 2 = 0.997,20 and 10000 ng/g for 5-ht r 2 = 0.994,ne r 2 = 0.993,and ep r 2 = 0.993,and 0.2 and 200 g/g for glu r 2 = 0.996 and gaba r 2 = 0.999 in the mouse brain tissues. as stated above,lc-ms/ms results were obtained and established to be a useful tool for the quantitative analysis of bh4,da,5-ht,ne,ep,glu,and gaba in the experimental rodent brain. © 2014 tae-hyun kim et al.