Determination of pentacaine, trans-2-(1-pyrrolidinyl)cyclohexyl-3-pentyloxycarbanilate hydrochloride, in biological samples by gas chromatography/mass spectrometry.
A quantitative and selective method has been developed for the determination of a novel local anaesthetic compound pentacaine, trans-2-(1-pyrrolidinyl)cyclohexyl-3-pentyloxycarbanilate hydrochloride, in biological samples. After ion pair extraction from 1 M HCl into 1,2-dichloroethane, pentacaine and a structurally related internal standard were derivatized to prevent thermal decomposition in the gas chromatograph. An on-column methylation technique with trimethylanilinium hydroxide was used. Determination was performed by gas chromatography/mass spectrometry (GC/MS) with selected ion monitoring. Interferences by endogenous lipophilic constituents were avoided by including an n-hexane wash before the ion pair extraction. This wash step did not reduce the drug recoveries. The method gave linear results over a concentration range of 5-100 ng ml-1 with a coefficient of variation less than 10% at 5 ng pentacaine ml-1. Specimens of plasma, whole blood, urine as well as in vitro preparations such as hepatic microsomes were successfully analysed.
Stefek
M
M
Benes
L
L
Kovácik
V
V
D000779:Anesthetics, Local / Q000032:analysis*; D000818:Animals; D002219:Carbamates / Q000032:analysis* / Q000097:blood / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D008862:Microsomes, Liver / Q000032:analysis; D051381:Rats
D000779:Anesthetics, Local; D002219:Carbamates; C010618:pentacaine