Abstract
A validated reversed-phase HPLC method has been developed for quantitative analysis of berberine in Berberis aristata fruits and in a polyherbal formulation. Separation of berberine was achieved on a C-18 column with a mobile phase consisting of a 10-80% acetonitrile gradient in 0.05% aqueous orthophosphoric acid. The flow rate was 1 mL min(-1). Detection was at 266 nm. A sharp, well defined peak was obtained at a retention time of 10.0 +/- 0.4 min. The method was validated in accordance with ICH guidelines for accuracy, precision, robustness, and the limits of detection (LOD) and quantification (LOQ). Results from linear regression analysis were indicative of a good linear relationship (r(2) = 0.998 +/- 0.0011) in a wide concentration range (5-500 mu g mL(-1)). LOD and LOQ were 1.5 and 5.3 mu g mL(-1), respectively. Satisfactory recovery results (94.6-103.1%) were obtained by the method of standard addition. Intra-day, inter-day, and inter-system precision was satisfactory, with relative standard deviation in the range 0.7-1.8%. The berberine content of fruit of Berberis aristata and the herbal formulation were 0.033% and 0.0089% (w/w), respectively. This HPLC method for quantification of berberine can be used for quality control and standardization of several crude drugs and different herbal formulations in which berberine is present as a phyto constituent.