Analysis of neuroactive amino acids from microdialysate samples by fluorescence detection using a modification of the 6‐aminoquinolyl‐<i>N</i>‐hydroxysuccinimidyl carbamate method

Abstract

A sensitive and rapid reversed-phase high-performance liquid chromatographic method using pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) and fluorescence detection is reported. By directly derivatizing microdialysate samples with AQC, an automatic and rapid simultaneous measurement of aspartate, serine, glutamate, glycine and histidine was developed. Excellent linearity (r2 > or = 0.998) was achieved for the standard mixture used for the validation experiments. Within-day and between-day precision was less than 6.2%, and the accuracy ranged from 95 to 105.2% in standards. This method is suitable for single run analysis of a high number of small volume microdialysate samples from rat hippocampus. Amino acids from microdialysate samples were quantified with RSD for reproducibility below 2%, and at approximately 0.1% for retention time.