Determination of dopamine and its metabolites in small volumes of rat brain dialysates using small-bore liquid chromatography with electrochemical detection.
A miniaturized liquid chromatographic system with electrochemical detection (LC-ED) was developed and applied to the analysis of dopamine and its metabolites in dialysate samples collected from the rat brain in vivo. An existing LC-ED system was down-scaled using a 1 mm I.D. small-bore column operated at a reduced flow-rate and with an injection volume of 1 microliter. With the small-bore system the limit of detection for dopamine of ca. 0.06 pg was almost 50 times less than with the conventional system, which represents a two-fold improvement in concentration sensitivity. Miniaturization was accomplished with negligible loss in resolution by using a conventional commercial amperometric detector with minor modifications. The results indicate that a number of useful advantages could be realized by the combination of this small-bore LC-ED system and the in vivo brain dialysis method.
D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis; D000818:Animals; D001923:Brain Chemistry; D002853:Chromatography, Liquid; D003956:Dialysis; D004298:Dopamine / Q000032:analysis*; D004563:Electrochemistry; D007202:Indicators and Reagents; D010477:Perfusion; D051381:Rats
D007202:Indicators and Reagents; D015102:3,4-Dihydroxyphenylacetic Acid; D004298:Dopamine