Determination of estrone using biotin-streptavidin complex

Estrone (E-1) was bound to bovine serum albumin (BSA) to get a complete ant igen (E-1 - BSA). A monoclonal antibody (McAb) specific for E-1 was then pr oduced by cell fusion after BALB/c mouse had been immunized with E-1 - BSA. Analysis revealed that anti - E-1 McAb (El - McAb) was of the IgG1 type, a nd its molecular weight was 164 000 daltons. The affinity constant of E-1 - McAb reacting with coated complete antigen was 8.2 x 10(8) L/mol. Biotin - streptavidin complex was used for the determination of E-1. The calibratio n curve of free E-1 covered a range of 10 similar to 10 000 pg/mL.