Determination of Six Thioguanine Nucleotides in Human Red Blood Cells Using Solid-Phase Extraction Prior to High Performance Liquid Chromatography

Abstract

A sensitive and rapid assay for the 6 thioguanine nucleotides (6TGN), major intracellular active metabolite of 6 Mercaptopurine, in human Red Biood Cells (RBCs) was developed. This assay is based on the hydrolysis of 6TGN to 6 Thioguanine (6TG) followed by a solid-phase extraction prior to HPLC analysis. A KROMASIL-C18 column was used to separate. Analytical recovery for 6TGN was 58 % (coefficient of variation 6 %). The limit of detection was 25 pmol per 8.10⁸ RBCs The assay was linear within the range 25–1600 pmol per 8.10^s RBCs. The advantage of this technique is that it does not require any toxic solvant. This assay may contribute to monitoring the patient's compliance in leukemic children undergoing 6 Mercaptopurine therapy.