Gas chromatographic-mass spectrometric determination of etomidate in mousebrain

A simple, rapid and reliable method was developed to determine the concentr ation of etomidate [ethyl-1-(1-phenylethyl)-1 H-imidazole-5-carboxylate] in mouse brain tissue by gas chromatography-mass spectrometry (GC-MS). Ethyl 5-amino-1-phenyl-4-pyrazolecarboxylate was used as internal standard (IS) a nd liquid-liquid extraction using ethyl ether as the solvent. The method de monstrated excellent recovery (93%) and a linear calibration range of 50-25 00 ng/0.2 g. Intra-day accuracy and precision had an error and coefficient of variation of less than 8.7% and 4.2%, respectively. The limit of detecti on was 1 ng in mouse brain. Our results suggest that this new method is sui table for the quantitative analysis of etomidate in mouse brain tissue. (C) 2000 Elsevier Science Inc. All rights reserved.