Development and Validation of a Novel Stability Indicating RP-HPLC Method for the Estimation of Entecavir in Tablet Formulation

Abstract

A precise and selective RP-HPLC method has been developed for the estimation of
entecavir in tablet dosage form. A Phenomenox C18 (250 x 4.6 mm i.d., particle size 5 µm)
column with, water (pH 3.0 adjusted by glacial acetic acid) and acetonitrile (95:5) was
employed as mobile phase. The flow rate of 1 mL/min was used and the effluents were
detected at 254 nm. The retention time was found to be 7.724 min. The method was further
validated for linearity, accuracy, precision, and robustness where the method was found to
be linear over the range concentration range of 5-30 μg/mL, accurate (recovery of about
99.2% with % RSD of <2), highly precise (% RSD of <2 in both intra-day and inter-day study),
and robust enough to deliver accurate results. Forced degradation studies of entecavir were
performed under neutral, acidic, alkaline conditions along with photolysis and oxidative
conditions, where the drug exhibited degradation and various peaks were monitored.
Highest degradation was observed under basic condition. Thus, this simple method will
help in determination of entecavir and the result of degradation studies will help in both
qualitative and quantitative determination of degraded products and may prove beneficial
in quality control of drug.