DETERMINATION OF BETA-AGONISTS IN URINE BY AN ENZYME-IMMUNOASSAY BASED ON THE USE OF AN ANTI-SALBUTAMOL ANTISERUM

An enzyme immunoassay (EIA) method for beta-agonists has been developed using an antiserum raised in rabbits by immunization against 3-O-salbutamol succinate coupled to bovine serum albumin. Horse radish peroxidase coupled to the same salbutamol derivative was selected as tracer. The dose of salbutamol which caused 50% binding inhibition was 16.8 pg per well and the limit of detection of the EIA directly performed on diluted urine was 0.14 ng ml- 1 in urine (when the variability of blank values in samples from untreated animals was taken into account). Owing to the large cross reactivities of the antibodies with a number of beta-agonists, the present assay is promising for the simultaneous determination of salbutamol, clenbuterol, mabuterol, terbutaline, cimaterol and probably also other beta-agonists with a tert-butyl or isopropyl group at the extremity of the aliphatic side chain of the molecule.