A simple and sensitive HPLC-UV method for quantitation of lovastatin in human plasma: application to a bioequivalence study.

An available, simple, sensitive, and rapid method has been developed for determination of the 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitor, lovastatin in human plasma. The analytical procedure involves a one-step liquid-liquid extraction method using atorvastatin as internal standard. Chromatographic separation was carried out on a reversed phase C(18) column using a mixture of 0.05 M phosphate buffer (pH 7) and acetonitrile (44.5 : 55.5, v/v) as mobile phase with UV detection set at 238 nm. The total run time of analysis was 6 min with the retention time of lovastatin being 4.3 min. A complete set of analytical method validation tests were carried out on the method. Accordingly, the method was linear in the wide range of 1-100 ng/ml. The limit of detection (LOD) and limit of quantification (LOQ) for lovastatin were 0.5 and 1 ng/ml, respectively. The method was shown to be precise with average within-run and between-run variations of 10.45+/-6.88 and 8.68+/-5.13%, respectively. The average within-run and between-run accuracy of the method throughout its linear range was 113.33+/-3.98 and 105.72+/-5.07%, respectively. The mean relative recovery of lovastatin from human plasma by the developed method was 88.61+/-7.00%. The applicability of the method in real pharmacokinetic situations was evaluated successfully during a bioequivalence study in 14 fasting healthy male volunteers.