We present an innovative concept of a screening tool for detecting free microcystin in cyanobacteria using a sandwich immunodetection format, based on Michael addition reaction between α,β-unsaturated carbonyl moiety of microcystin and thiol of coating substance. This proof-of-concept immunoassay was developed using bovine serum albumin as a microcystin-binding model, and was tested with toxic Microcystis samples. The preliminary results indicate that the proposed Michael addition-based immunodetection is promising and can be used as a platform for further development to become a useful tool for free microcystin analysis in various samples in the future.
Keywords: ELISA; Michael addition reaction; Microcystin; free form; sandwich immunoassay.