Determination of atenolol in human urine by using HPLC

A simple high-performance liquid chromatography method has been developed for determination of atenolol in human urine. The method was validated on Ace C-18 column using fluorescence detection. The mobile phase consisted of methanol/water (50:50, v/v) containing 0.1% trifluoroacetic acid. Fluorescence detection was performed at 276 nm (excitation) and 296 nm (emission). The calibration curve was linear between the concentration range of 5-150 ng/mL. Intra- and inter-day precision values for atenolol in human urine were less than 6.09, and accuracy (relative error) was better than 5.50%. The extraction recoveries of atenolol from human urine were between 93.0 and 98.8%. The limits of detection and quantification of atenolol were 1.5 and 5 ng/mL, respectively. Also, the method was successfully applied to a patient with hypertension who had been given an oral tablet of 50 mg atenolol.