Determination of colchicine in mouse plasma by high performance liquid-chromatographic method with UV detection and its application to pharmacokinetic studies

A simple and sensitive high performance liquid chromatography method with UV detection was described for the determination of colchicine (COL) in mouse plasma. After single-step deproteinization by acetonitrile using berberine hydrochloride as an internal standard (I.S.), solutes were separated on a Diamonsil C-18 column (250 mm X 4.6 mm I.D., 5 mu m particle size) (Dikma), using acetonitrile-0.15% phosphoric acid solution (27 : 73, v/v) as mobile phase (flow-rate 1.0 ml/min); wavelength of the UV detector was set at 350 nm. No interference from any endogenous substances was observed during the elution of COL and internal standard (I.S., berberine hydrochloride). The retention times for COL and I.S. were 11.23 min and 8.82 min, respectively. The limit of quantification was evaluated to be 1.5 ng/ ml and the limit of detection was 0.5 ng/ml. The method was used in the study of pharmacokinetics of COL after intravenous injection (i. v.) and intraperitoneal injection (i.p.). The result indicated that COL disappears from the plasma according to a three compartment open model.