Production and characterization of antibodies to meperidine

A mepridine-bovine serum albumin (Mep-BSA) conjugate with 15-20 moles of meperidine per mole of BSA was synthesized and characterized. Rabbits immunized with Mep-BSA produced antibodies that were assayed utilizing saturated ammonium sulfate to separate 3H-meperidine (3H-M) bound to antibody from free 3H-M. Antibody specificity was assessed by competitive inhibition studies. The nanomoles of inhibitor required to decrease the binding of 3H-M by 50% were: meperidine .046; meperidine acid, 3.2; alphaprodine, 7.8; dextromethorphan, 20; codeine, 50; and morphine 55. The sensitivity of the assay is approximately 30 ng/ml; sufficient for pharmacokinetic studies of the disposition of meperidine in man.