Development and validation of novel rp-hplc method for the simultaneous estimation of ellagic acid and quercetin in an ayurvedic formulation

Abstract

Objective: To develop a novel, accurate, precise and linear reverse phase high performance liquid chromatographic (RP-HPLC) method for simultaneous qualitative and quantitative estimation of ellagic acid and quercetin in an ayurvedic formulation and validate as per international conference on harmonization (ICH) guidelines. Methods: In the present work, good chromatographic separation was achieved isocratically using a shim-pack HPLC C18 column (4.6 x 250 mm, 5µm) and a mobile phase consisting of 0.02 M potassium dihydrogen orthophosphate buffer (pH adjusted to 3.5 with orthophosphoric acid) and acetonitrile in the ratio 60:40, at flow rate of 1.2 ml/min and column temperature maintained at 35 °C. The effluents obtained were monitored at 255 nm with UV-visible detector. Results: The retention time of ellagic acid and quercetin were found to be 1.65 min and 2.94 min respectively. Linearity of ellagic acid and quercetin were tested in the range of 6-14 ppm and 3-11 ppm respectively. The correlation coefficient for ellagic acid and quercetin were 0.997 and 0.993 respectively. The high recovery values (98 %-102 %) indicate a satisfactory accuracy. The low percent relative standard deviation (% RSD) values in the precision study reveals that the method is precise. Conclusion: The developed method is novel, simple, precise, rapid, accurate and reproducible for simultaneous quantitative estimation of ellagic acid and quercetin in an ayurvedic formulation. Hence the developed method can be used for quantitative analysis and quality control of extracts and commercial samples of other plant species and formulation containing these two markers.