New Validated Analytical Method for Determination of Simvastatin in Tablet Formulations by RP–HPLC

RP–HPLC method has been developed and validated for the determination of simvastatin (SVS) in pure form and in tablets. Fluvastatin sodium was used as internal standard. The determination was performed on Nucleodur column C8 (250×4.6 mm i.d., 5 µm particle size); the mobile phase consisted of a mixture of phosphate buffer solution (KH2PO4 0.05 M, pH 4.83) and methanol (20:80, v/v), pumped at a flow rate 1.0 mL min−1 . Analyte was monitored by UV detection at 230 nm. The mean retention times for fluvastatin and simvastatin were about 4.40 and 9.00 min, respectively. The method was proved linear in the range of 3.5– 550.0 µg mL-1 and exhibited good correlation coefficient (r>0.9998) and excellent mean recovery (100.71– 102.18%). Very good limit of detection of 0.63 µg mL-1 was found for SVS. The method was validated statistically and by recovery studies for linearity, precision, repeatability, and reproducibility. This method was successfully applied to the determination of simvastatin content in four marketed brands from Syria. A good agreement between this method with the pharmacopoeial method for the determination of simvastatin in some real samples demonstrates that the proposed method is suitable to quantify simvastatin in pharmaceutical formulations.