Monitoring excitatory amino acid release in vivo by microdialysis with capillary electrophoresis-electrochemistry.
Capillary electrophoresis (CE) with electrochemical detection (ED) was used to determine extracellular levels of aspartate, glutamate and alanine in samples from the frontoparietal cortex of the rat which were obtained by microdialysis. The method was used to monitor the effect on the overflow of the excitatory amino acids aspartate and glutamate of an influx of high concentrations of potassium ion. Samples were derivatized with naphthalenedialdehyde-cyanide prior to analysis. Detection limits for aspartate and glutamate were 80 and 100 nM, respectively. CE-ED is extremely useful for the analysis of microdialysis samples because of the very small sample volumes required by this analytical technique. The use of ED provides the requisite sensitivity and allows verification of peak purity by voltammetry.
O'Shea
T J
TJ
Center for Bioanalytical Research, University of Kansas, Lawrence 66047.
Weber
P L
PL
Bammel
B P
BP
Lunte
C E
CE
Lunte
S M
SM
Smyth
M R
MR
D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D001923:Brain Chemistry; D003956:Dialysis; D004563:Electrochemistry; D004586:Electrophoresis; D007202:Indicators and Reagents; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
D000596:Amino Acids; D007202:Indicators and Reagents; D011188:Potassium