Ion pairing RP-HPLC analytical methods for simultaneous estimation of simvastatin and its â-hydroxy acid

Abstract

Sensitive HPLC assay methods for Simvastatin (SV), a hypolipidemic agent, and its corresponding â-hydroxy acid (SVA), were developed and validated for their simultaneous estimation in solutions of various studies. HPLC separations were achieved on (i) C₈ Lichrocart® Lichrosphere® (ii) CN Lichrocart® Lichrosphere® and (iii) C₁₈ Phenomenex® columns. The eluents were monitored by diode array detector at 240 nm. Retention times were: SV, 8-9; and SVA, 5.5-6 min. The lower limit of detection of both SV and SVA on C₁₈ column was 0.05 μg/ml and on C₈ and CN columns was 0.1 μg/ml. Reproducibility of the method were determined by inter and intra assay precision (< 6%).