Determination of free aspartic acid enantiomers in rat brain by capillary electrophoresis with laser-induced fluorescence detection

Quantification of aspartic acid enantiomers in rat brain by using a chiral capillary electrophoresis procedure is described. Amino acids were pre-colu mn derivatized with naphthalene-2,3-dialdehyde. Enantiomeric separation was achieved by micellar electrokinetic chromatography in the presence of meth anol and beta -cyclodextrin as chiral selector. The chiral separation was c oupled with laser-induced fluorescence detection. Contents Of D- and L-aspa rtic acids in rats at different stages of growth (from I day before birth t o 90 days after birth) were determined. D-Aspartic acid was detected in all the brain tissue samples tested, but at different levels. In the cerebrum of rats I day before birth, D-aspartic acid was found to be at the highest concentration of 81 nmol/g wet tissue. The level of D-aspartic acid in rat brain falls rapidly after birth, while the L-aspartic acid level increases with age, (C) 2001 Elsevier Science B.V. All rights reserved.