AUTOMATION AND VALIDATION OF THE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC-RADIOIMMUNOASSAY METHOD FOR THE DETERMINATION OF LACIDIPINE IN PLASMA

The automation and validation of the HPLC-radioimmunoassay (RIA) metho d for the determination of lacidipine are reported. The solid-phase ex traction step was automated by the introduction of the ASPEC system. A two-column system was adopted for the HPLC purification. The RIA was converted from heterogeneous to homogeneous by the scintillation proxi mity assay system and automated using an automatic dilution system. Al l characteristics in terms of accuracy, precision, specificity, and li nearity resulted similar to the manual version. The quantification lim it was set to 40 pg/ml. The new version of the method increased the nu mber of samples assayed per month two- to three-fold.