title: Reversed-phase high-performance liquid chromatography analysis of 6-thioguanine applicable to pharmacologic studies in humans.
abstract: 6-thioguanine (6TG) and its metabolites were analyzed in human plasma with a reversed-phase high-performance liquid chromatographic methods. 6TG and related compounds were extracted from plasma with an equal volume of 2 N perchloric acid at a 50-100% recovery efficiency. The neutralized extracts were chromatographed on a muBondapak C18 column by two separate isocratic conditions. 6TG, 6-thiouric acid, 6-thioxanthine, 6-thioguanosine, and 6-methylthiouric acid were analyzed with 0.01 M sodium acetate, pH 3.5-10% methanol as the mobile phase and 340 nm for detection. 6-Methylthioguanine and three unknown metabolites were separated with acetate-25% methanol and 310 nm detection. One of the unknowns was identified as 6-methylthioguanosine. External standard calibration was used for quantitation. The 6TG detection limit was 0.8 nmol/ml in plasma.
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D013866:Thioguanine / Q000097:blood* / Q000378:metabolism / Q000652:urine
chemical_list: D013866:Thioguanine