VALIDATION OF HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHODS ON 2 SILICA BASE-DEACTIVATED REVERSED PHASES FOR THE DETERMINATION OF CHLOROPROCAINE AND BUPIVACAINE

The separation by HPLC of basic drugs on silica-based reversed phases remains a major problem because of the interaction between the residua l silanol groups of the silica and the amino function of the drug. Thi s paper describes the validation of HPLC methods for the determination of two injectable solutions of basic drugs (two local anaesthetics, c hloroprocaine and bupivacaine), with two commmercial base-deactivated reversed phases. These columns improve the chromatographic performance s without adding a blocking agent to the mobile phase. With a simple a queous-organic mobile phase, these base-deactivated reversed phases gi ve high theoretical plate numbers (N) and small tailing factors. The o ptimized methods show good linearity, precision (RSD < 2%) and accurac y (bias < 2% for dosage forms). The limits of detection and quantitati on are lower than the maximal accepted limits for impurities. These me thods are currently in routine use in stability studies.