Development and validation of analytical method for estimation of rosmarinic acid in herbal formulation

Rosmarinic acid is a naturally occurring polyphenolic compound. It belongs to class of ester as 3, 4-dihydroxyphenyllactic acid ester of caffeic acid. Rosemary is considered one of the most important sources for the extraction of phenolic compounds with strong antioxidant activity. The present study was designed with an objective to develop and validate a simple, rapid, precise, accurate and specific HPTLC method for the determination of Rosmarinic acid from herbal formulation. High performance thin layer chromatography (HPTLC) method was developed and validated for rapid analysis of determination of Rosmarinic acid. Chromatographic separation was achieved on precoated silica gel HPTLC aluminum plate 60 F254 using toluene: ethyl acetate: formic acid (4:5:1). Detection was performed at 330nm wavelength. The Rf value for Rosmarinic acid was found to be 0.55±5%. Linearity was observed in the concentration range of 200-1200ng/band for Rosmarinic acid. The limit of detection and limit of quantitation were found to be 0.64ng/band and 1.94ng/band respectively for Rosmarinic acid. The method was validated according to the ICH guidelines with respect to precision, accuracy, linearity, robustness and specificity. The developed method can be used for routine quality control analysis of Rosmarinic acid in herbal formulation.