Determination of β-agonists in urine by an enzyme immunoassay based on the use of an anti-salbutamol antiserum

Abstract

An enzyme immunoassay (EIA) method for β-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 β-agonists, the present assay is promising for the simultaneous determination of salbutamol, clenbuterol, mabuterol, terbutaline, cimaterol and probably also other β-agonists with a tert-butyl or isopropyl group at the extremity of the aliphatic side chain of the molecule.