Determination of thioproline in plasma using high performance liquid chromatography

The determination of thioproline in plasma of cancer patients, using high performance liquid chromatography (HPLC) is reported. As column support, a silica-bonded cation exchanger was used. Detection was performed at 205 nm. The detection limit of the method was 5 X 10(-6) M and the linear dynamic range was over 500. No sample clean-up procedure was necessary other than deproteinization of the plasma. The method was applied to the measurement of plasma drug levels in 3 patients, part of a clinical trial testing the effectiveness of thioproline as an anti-cancer agent.