Development of RP-HPLC-DAD method for quantitative analysis of quercetin and piperine in botanical extracts

A simple, effective, and fast reversed-phase high-performance liquid chromatographic method was devised to separate and quantitatively determine quercetin and piperine in herbal extract. the analytes were eluted on the Intersil C18 ODS column (150 mmx4.6 mm, 5 mu m) as a stationary phase with a gradient elution technique. The mobile phase was composed of a mixture of water (with 0.1% formic acid) and methanol (with 0.1% formic acid) and the gradient program of 30 minutes was optimized. The mobile phase flow rate was adjusted to 1 mL min-1 for 20 mu L injection volume. The eluents were detected by the PDA detector at 342 nm wavelength. At the optimized chromatographic conditions, the developed method was validated for the parameters including system suitability, specificity, linearity, accuracy, precision, and robustness per the ICH Q2(R1) guidelines. The developed method was applied for the determination of quercetin and piperine in the prepared herbal extract.