A gas chromatographic method for measuring 6-mercaptopurine in serum

✍ Scribed by D.G. Bailey; T.W. Wilson; G.E. Johnson

• Publisher: Elsevier Science
• Year: 1975
• Tongue: English
• Weight: 517 KB
• Volume: 111
• Category: Article
• ISSN: 1873-3778
• DOI: 10.1016/s0021-9673(00)99279-3

✦ Synopsis

A method is presented for the measurement of 6-mercaptopurine (6-MP) in serum. Serum samples containing the drug were treated with dithioerythritol and saturated with ammonium carbonate. 6-MP was then extracted from the serum with a mixture of isopropanol-ethyl acetate (I:], v/v) containing 0.1 'A, ethanethiol. The solvent was evaporated, the residue dissolved in dilute hydrochloric acid, washed with chloroform, and extracted with ethyl acetate. 6-MP was derivatizcd with trimethylanilinium hydroxide and measured gas chromatographically. The sulfhydrylprotecting reagents, dithiocrythritol and ethancthiol, were added to prevent the decomposition of G-MP. The extraction and clean-up method rccovcred 723 rfi: 2% (S.E.) of the G-MP present. Tracer amounts of [8-*JC]-G-MP served as the internal standard during the extraction part of the method. Thcophylline was used as the internal standard during the gas chromatographic analysis. The standard curve obtained from the gas chromatograph was linear between 0.5 and 20 [/g/ml of 6-MP. Serum samples were stored .in the freezer for two weeks witllout significant loss of drug. No interference was encountered from normal strum constituents or xanthines. such as caffeine or theophyllinc added to strum.