Claudia Schildböck, Stephan Harm and Jens Hartmann
Thiopurine drugs, including Azathioprine and 6-Mercaptopurine (6-MP), are used in clinical practice for more than 50 years. Their bioavailability is strongly patient-dependent. Therefore, closely monitoring of the plasma levels during therapy is recommended. Here, we present a quick and simple High Performance Liquid Chromatography (HPLC) based method for the quantification of 6-MP in human plasma. Samples were deproteinized with methanol to obtain protein concentrations below 2 mg/dL. The method offers a recovery higher than 90% and is precise and linear with a high correlation coefficient and a level of detection.