Liquid Chromatography Determination of Thiopentone in Human Plasma

Abstract

A rapid microprocedure for the liquid chromatographic analysis of thiopentone, an anesthetic, in plasma is described. Reversed-phase liquid chromatography was performed on a microparticulate C18 column using as a mixture of 60% methanol/40% water as mobile phase and UV detection (290 nm). The method used carbamazepine as internal standard and ethyl acetate as extraction solvent. The analytical recovery was 95%; the reproducibility, 6.5%; and the sensitivity limit of detection, 0.2 mg/l. The method has been used in preliminary studies to determine the plasma concentrations in patients receiving thiopentone by the i.v. route. A method using direct injection is described.