A. Lommen et al., NUCLEAR-MAGNETIC-RESONANCE CONTROLLED METHOD FOR COUPLING OF FENOTEROL TO A CARRIER AND ENZYME, FOOD AND AGRICULTURAL IMMUNOLOGY, 7(2), 1995, pp. 123-129
Fenoterol is a phenethanolamine with beta-adrenergic agonist activity.
The development of an enzyme immunoassay for fenoterol requires coupl
ing to a carrier (bovine serum albumin, BSA) and an enzyme (horseradis
h peroxidase, HRP). 1,4-Butanediol diglycidyl ether was used as the co
upling agent, providing for a 12-atom spacer. During the coupling proc
edure of the spacer to the protein and fenoterol to the spacer the cou
pling yield was monitored by nuclear- magnetic resonance (NMR). This e
nsured a coupling at desired hapten: protein ratios. The average coupl
ing ratios obtained using this method were 30 moles of fenoterol ol to
1 mole of BSA and 1 mole of fenoterol to 1 mole of HRP. In practice,
this method can be used for the coupling of compounds containing pheno
lic, anilinic, primary amine and thiol groups to proteins. Its major a
dvantage is the real-time NMR quantification of coupling efficiency an
d the option to interrupt the coupling reaction to obtain the desired
hapten:protein ratio.