VALIDATION OF A HPLC METHOD FOR ATENOLOL DETERMINATION IN HUMAN PLASMA
An HPLC method with fluorescence detection for atenolol determination in human plasma was developed and validated, using metoclopramide as internal standard. After protein precipitation with perchloric acid, atenolol was separated at 30 °C on a C18 column, 150 mm x 4.6 mm, 5 µm. The mobile phases consisted of a mixture of acetonitrile:sodium dihydrogen phosphate 40 mM, pH 3 with phosphoric acid 85%, 10:90 (solvent A), and acetonitrile (solvent B). The elution was made in gradient mode: 0-4 min 0%B, 4-8 min 30% B, 8-13 min 0%B, at 1 ml/min. The excitation and emission wavelengths were Ex/Em = 235/ 315 nm for 7.5 min, and 309/356 until 13 min. The method was linear between 10-1000 ng/ml, with an accuracy and precision of -8.6¸6.3 %, being between -18.7% and 9.8% at lower limit of quantification. The method was applied for atenolol determination in human plasma after oral administration of 100 mg atenolol.