Comparison of Luminescent Immunoassays Using Biotinylated Proteins of Aequorin, Alkaline Phosphatase and Horseradish Peroxidase as Reporters

Abstract

We compare aequorin, alkaline phosphatase and horseradish peroxidase as reporters for luminescent immunoassays using α-fetoprotein (AFP) as a model analyte. Biotinylated aequorin was prepared from mutated aequorin containing a reactive cysteine residue by chemical conjugation. The measurable range of AFP using this biotinylated aequorin was 0.02–200 ng/ml, with a lower background level than the other biotinylated enzymes tested.