Development of innovative methodology for determination of 6-thioguanine in whole blood erythrocytes by HPLC–PDA-based technique for medical diagnostics purposes

The HPLC method was developed for the determination of 6-thioguanine (6-TG) in whole blood samples containing red blood cells (RBCs) using 5-bromouracil (5-BU) as internal standard (IS) was developed. A mobile phase consisting of ACN/buffer KH₂PO₄ (3/97, v/v) with 50 µl H₃PO₄ in isocratic flow was used. 6-TG was detected at wavelength 341 nm and 6-BU at 280 nm. Under the chromatographic conditions, both the compounds and the biological background were well separated. A simple and rapid method of releasing 6-thioguanine nucleotides from erythrocytes by perchloric acid and then…