Determination of lisinopril using anion exchange chromatography with integrated pulsed amperometric detection

A rapid and practical method for direct detection of lisinopril in anion exchange chromatography (AEC) has been developed with integrated pulsed amperometric detection (IPAD). Dionex AS18 (250 mm × 2 mm) and AG18 (50 mm × 2 mm) columns and 40 mmol/L NaOH solution were used for separation. Multi-step potential waveform parameters were optimized to maximize the signal-to-noise ratio (S/N). Utilizing the optimized waveform, the repeatability (intra-day) precision and intermediate (inter-day) precision were obtained with relative standard deviation (RSD) of 0.74, 0.93, respectively. The limit of quantification (LOQ) and limit of detection (LOD) were found to be 0.37, 0.12 ng/mL, respectively, with the correlation coefficient of 0.9998 over concentration range 0.01–1 μg/mL. The present method was successfully applied to the determination of lisinopril in human plasma. The recoveries of plasma sample spiked by 0.2 μg/mL, 0.8 μg/mL lisinopril were 98.31–103.23% with RSD of 1.41%, 0.61%, respectively.