Impedimetric immunoassay for aflatoxin B1 using a cysteine modified gold electrode with covalently immobilized carbon nanotubes

摘要: The authors describe a label-free electrochemical biosensor based on CNTs for picogram range detection of the food carcinogen aflatoxin B1 (AFB1). A gold electrode was modified with cysteine (Cys) self-assembled layer, and carboxyl-functionalized carbon nanotubes were covalently attached to Cys subsequent tethering antibody against AFB1 (anti-AFB1). Topographical images surface acquired by atomic force microscopy throughout modification assay procedure. Upon exposure samples containing AFB1, its binding anti-AFB1 will result in change electrical conductivity. use CNT warrants enhanced properties, charge-transfer resistance (Rct) can be related concentration AFB1. Biosensor selectivity tested using ochratoxin A. displays limit as low 0.79 pg·g−1, response is linear 0.1 20 pg·g−1 range. applied determination contaminated corn flour at concentrations so that they cannot quantified established ELISAs. In our perception, this method represents viable point-of-care probe