Determination of sildenafil citrate content by capillary zone electrophoresis / 第二军医大学学报

ABSTRACT

Objective: To establish capillary zone electrophoresis method for determination of sildenafil citrate (Viagra) content in its troche. Methods： Using tetrandrine as internal standard(IS), the electrophoretic separation was achieved with 25 mmol/L borate (pH=7.89) running buffer. And a voltage of 14 kV was applied to the 40 cm×75 μm(i.d) capillary. The analytes were introduced into capillary by siphon (1 s) and determined with on-column monitoring at 214 nm. Results：The determination could be completed within 4 min and the minimum concentration of detection was 5 μg/ml.The analytical results of sildenafil citrate samples demonstrated a good linear relationship within the range of 24-480 μg/ml.The relative standard deviations (RSD) of intra-day was less than 1.58% and that of inter-day was less than 2.46%.The present recoveries were between 95%-105％. Conclusion：The CZE method is accurate, simple, rapid and reliable, so it can be applied to the determination of sildenafil citrate content.