Hemin as a peroxidase substitute in mimetic enzyme immunoassay for hepatitis B surface antigen
- 化学化工－已发表论文 
A novel mimetic enzyme immunoassay method was developed for the determination of hepatitis B surface antigen(HBsAg) in solution. Hemin, a horseradish peroxidase substitute, was used as a labelling reagent to catalyze the reaction of thiamine, a new fluorogenic substrate, with hydrogen peroxide at pH 8.5. In the sandwich immunoassay, anti-HBsAg antibody was coated on a 96-well plate(polystyrene), which first reacted with standard HBsAg solution, and then further reacted with the fixed amount of hemin-labelled anti-HBsAg. After the two-step immunoreaction, the immunochemically adsorbed hemin-anti-HBsAg conjugate moiety was determined by measuring the fluorescence produced in a solution containing thiamine and hydrogen peroxide. The flourescence intensity was directly proportional to the concentration of HBsAg. The calibration graph far HBsAg was linear over the range 2.5 similar to 500 ng/well with a detection limit of 2.5 ng/well.