Determination of imatinib mesylate and related compounds by field amplified sample stacking with large volume sample injection capillary electrophoresis

Imatimib mesylate is a drug for the treatment of gastrointestinal stroma tumor and chronic myelogenous leukemia. In this study, capillary electrophoretic analysis of imatinib mesylate and related compounds was developed. The optimized separation condition was NaH2PO4 (10 mM) aqueous solution containing 5 mM of 2-hydroxypropyl-β-cyclodextrin at a pH of 2.0. The separation could be obtained in less than 20 min when the separation voltage was 20 kV. To enhance the sensitivity, field amplified sample stacking combining with large volume sample injection was adopted. The optimal injection conditions were obtained by using methanol containing 0.5 mM HCl as the sample dilution solution and performing injection at a voltage of 15 kV for 60 s. The linearity ranges of ima amine, N-desmethyl imatinib and imatinib mesylate were 0.005–0.500 μg/ml, and 4-chloromethyl-N-(4-methyl-3-((4-(pyridin-3-yl) pyrimidin-2-yl) amino) phenyl) benzamide was 0.010–0.500 μg/ml, with good linear correlation coefficients (r2 > 0.9900). The intra-day and inter-day relative standard deviations of peak areas were satisfactory. Under the optimized condition, five batches of the synthesized samples were detected and ima amine was found in all the batches. Due to its simplicity, effectiveness and low price, the developed method can be used for quality control analysis of imatinib mesylate.