Method Development and Validation for the Estimation of Valerenic Acid Content in Valerian Tablets Using RP-HPLC Method

Abstract

Valerian (Valeriana officinalis) has been used from so long as a traditional medicine since it has therapeutic effects such as enhances sleep, acts as an anxiolytic for nervous unrest etc. For determining the dose of herbal formulations and to estimate the quality of dosage form, we need to develop an effective reproducible validated method for the determination of the bioactive molecules essential for the sedative activity of the valerian tablets. So, the primary objective of the present work was to develop an efficient and sensitive method for the determination of valerenic acid content in valerian tablets using reverse-phase high-performance liquid chromatography technique. Since it is RP-HPLC method the column used was Phenomenex C18 Luna® 5 µm (250 x 4.6mm) column. The LC system used was Shimadzu UFLC, Nexera series utilizing a Photo-diode Array detector (SPD-M20A) detector and the software used was LC Solutions. The mobile phase used is acetonitrile: Ortho-phosphoric -acid in the ratio of 97:3 v/v. Ortho-phosphoric acid (gradient mode) employed was of 5% solution with a pH of 3.5. The chromatographic conditions employed are 1ml/min flow rate and absorbances were observed at 220 nm. The selected chromatographic conditions were found to give effective separation of Valerenic acid at 4.4±0.2 min. Validation was carried out for linearity, system suitability, accuracy, precision (intra-day and inter-day), and robustness, the limit of detection and limit of quantification which were found to be within acceptable limits according to ICH Guidelines. Thus, the method proposed was found to be accurate, precise, reproducible and analyte-specific. In this work, based on the observations made from the literature review a relatively best suitable method was developed for the estimation of valerenic acid in valerian tablets with shortened retention time along with better resolution thus, reducing the wastage of solvents and the time of analysis.