LC SEPARATION AND INDUCED FLUOROMETRIC DETECTION OF RIVASTATIN IN BLOOD-PLASMA

An LC procedure suitable for quantitative analysis of pg ml(-1) concen trations of the HMG-CoA reductase inhibitor rivastatin in blood plasma was developed. The procedure involves an extraction step, chromatogra phy on an ODS column, and fluorometric detection of a post-column phot olytic decomposition product that was isolated and identified. The ach ieved quantitation limit (25 pg ml(-1)) facilitated analysis of relati vely low rivastatin concentrations in plasma that were observed after 100-300 mu g oral doses of rivastatin. At 25 pg ml(-1) concentration t he RSD ranged from 3.6 to 13.5% and mean deviation from the nominal va lue was 8.0%; at 8 ng ml(-1) the RSD range was 0.7-3.6% while the mean deviation was -1.8%. The concentrations obtained with the LC procedur e were compared to the concentrations obtained with a specific but les s sensitive capillary GC method and a radioimmunoassay (RIA) procedure . Concentrations obtained with the HPLC and GC procedures agreed withi n experimental error; the RIA concentrations were about 30% higher.