Abstract
A method for the separatory determination of d-and l-pentazocine in blood plasma by radio-immunoassay has been developed. In order to obtain the optically specific antiserum to l-pentazocine a hapten-carrier conjugate was prepared from l-pentazocine 2'-carboxymethyl ether by coupling with bovine serum albumin (BSA) by the mixed anhydride technique. The antiserum raised against this antigen proved to be highly specific to l-pentazocine by cross-reaction studies with the closely related compounds. The anti-dl-pentazocine antiserum was similarly produced by immunization with dl-pentazocine 2'-carboxymethyl ether-BSA conjugate. These antisera were used for radioimmunoassay where the B/F separation was carried out by the 50% ammonium sulfate method. The amount of the d-enantiomer was estimated indirectly by simultaneous quantitation of the l-enantiomer and total pentazocine. The blood levels of d- and l-pentazocine in man administered an officinal dose of the racemate were determined by the established method.
