Enzyme immunoassay of bradykinin using β-d-galactosidase as a labeling enzyme

摘要: Abstract An enzyme immunoassay of bradykinin, using β- d -galactosidase from Escherichia coli as a labeling enzyme, is described. Bradykinin, conjugated to the with hetero bifunctional type coupling agent, N-(m-maleimidobenzoyloxy)succinimide, was prepared labeled antigen, Antisera against bradykinin were obtained male rabbits immunized linked albumins (ovalbumin or bovine serum albumin) toluene 2,4-diisocyanate l-ethyl-3-(3-dimethylaminopropyl) carbodiimide. These antisera tested for their abilities bind antigen and sensitivities. The antigen-antibody reaction performed in an ice bath 18 hr; this incubated another 4 hr, after addition anti-rabbit IgG antiserum goat (double antibody method) separate bound free antigen; activity precipitate measured fluorogenic substrate. Some showed good sensitivity when assayed by method, having been comparable that radioimmunoassays bradykinin. With 30 pg/tube (0.2 ml) could be measured, standard curve range pg 10 ng kininogen level human plasma determined conversion trypsin heating at 60°. Kininogen levels six subjects agreement those bioassay.