Abstract:

The detection of small molecules mainly employs competitive immunoassay format due to their single epitopes
that cannot be simultaneously recognized by two antibodies, which has limited the application of the sandwich immunoassay
in the detection of small molecules. In recent years, the successful application of novel recognition receptors, such as
biosynthetic antigen, nanobody, anti-idiotypic antibody, has opened up a new field of small molecule immunoassay
technology. In this paper, an overview of the latest development and application of these approaches is presented from the
perspective of recognition receptors. Furthermore, future development trend is also discussed.

Key words: small molecules, immunoassay, recognition receptor