Assay of 6-thioinosinic acid and 6-thioguanine nucleotides, active metabolites of 6-mercaptopurine, in human red blood cells

doi:10.1016/0378-4347(87)80340-7

Journal of Chromatography B: Biomedical Sciences and Applications

Volume 423, 1987, Pages 169-178

https://doi.org/10.1016/0378-4347(87)80340-7 Get rights and content

Abstract

A highly sensitive reversed-phase high-performance liquid chromatographic assay, with ultraviolet detection, for 6-thioinosinic acid and the 6-thioguanine nucleotides (6TGNs) was developed. The 6TGNs are major red blood cell metabolites of the immunosuppressive agent azathioprine and the cytotoxic drugs 6-thioguanine and 6-mercaptopurine. The assay is based on the specific extraction, via phenyl mercury adduct formation, of the thiopurine released on acid hydrolysis of the thionucleotide metabolite. Red blood cell 6TGN concentrations in eighteen leukaemic children receiving chronic 6-mercaptopurine chemotherapy were measured and compared to a previously published spectrophotofluorometric assay. Linear regression analysis gave r = 0.991; P < 0.001; y = 40 + 0.94x.

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Assay of 6-thioinosinic acid and 6-thioguanine nucleotides, active metabolites of 6-mercaptopurine, in human red blood cells

Abstract

Anal. Biochem.

Lancet

J. Chromatogr.

J. Chromatogr.

Anal. Biochem.

J. Chromatogr.

Biochem. Pharmacol.

J. Chromatogr.

Cancer Res.

J. Pharm. Pharmacol.

Cancer Res.