Development and characterization of a capillary electrophoresis instrument with laser-induced fluorescence detection for on-line monitoring of glutamate in vivo via microdialysis

Abstract

To elucidate the roles of key neurochemicals in the metabolic suppression of Arctic ground squirrels, a technique is required that is capable of on-line, in vivo, high temporal resolution, quantitative detection of neurotransmitters. A capillary electrophoresis instrument has been built that is coupled to microdialysis by flow-gated injection. Primary amines recovered in vivo via microdialysis are derivatized on-column by cyanide-catalyzed formation of fluorescent isoindoles with naphthalene-2,3-dialdehyde for laser-induced fluorescence detection. The system is capable of detecting base-line glutamate in vivo in 15-second intervals.