Detection of gamma-aminobutyric acid in a living rat brain using in vivo microdialysis-capillary electrophoresis/mass spectrometry.

Coupling of in vivo microdialysis with capillary electrophoresis/mass spectrometry (MD-CE/MS) was demonstrated. A microdialysis probe was inserted in the striatum of a rat brain and gamma-aminobutyric acid (GABA) in the brain was detected by CE/MS without any chemical treatment of the sample. MD-CE/MS is expected to be a useful technique for analyzing brain substances, because of the relatively small damage it causes to a living structure and the high selectivity of the analytical technique.