Rapid determination of atenolol in human plasma and urine by high-pressure liquid chromatography

A rapid, specific, high-pressure liquid chromatographic determination of atenolol in plasma and urine was developed. This method employs the high sensitivity of fluorescence detection together with selective extraction and reversed-phase chromatography to measure concentrations as low as 20 ng of drug/ml of plasma with a coefficient of variation of 3.91%. The assay is specific enough to be valid in the presence of plasma and urine substances. The detection limit (i.e., three times baseline noise) is 3 ng/ml.