title: Analysis of 6-mercaptopurine in human plasma with a high-performance liquid chromatographic method including post-column derivatization and fluorimetric detection.
abstract: A relatively simple assay with improved reliability and sensitivity for measuring levels of 6-mercaptopurine in human plasma is presented. After extraction of the compound and the added internal standard with phenyl mercury acetate, samples were separated by ion-pair reversed-phase high-performance liquid chromatography. On-line the analytes were oxidized to fluorescent products and detected in a flow-fluorimeter. The within-day coefficient of variation was 3.8% at a concentration of 25 ng/ml. The lower detection limit was 2 ng/ml when 1.0 ml of plasma was used. Mercaptopurine concentration versus time curves of two subjects after a single oral dose of azathioprine are shown.
mesh_terms: D001379:Azathioprine / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005470:Fluorometry; D006801:Humans; D015122:Mercaptopurine / Q000097:blood*; D013997:Time Factors
chemical_list: D015122:Mercaptopurine; D001379:Azathioprine