A nanowell-based molecularly imprinted electrochemical sensor for highly sensitive and selective detection of 17β-estradiol in food samples.

A novel electrochemical sensor was developed combination molecularly imprinted polymers (MIPs) with nanowell technology, and which was utilized for sensitive and selective 17β-estradiol (17β-E2) detection. A nanowell gold film with a thickness of 120 nm and a pore size of ∼20 nm was immobilized onto gold electrode surface to form a nanowell-based electrode. MIPs was then synthesized onto the nanowell-based electrode using electro-polymerization method, and then the nanowell-based MIP electrochemical sensor was formed. This sensor surface exhibited 3D-nanowell structure with higher surface area and enhanced electron-transport ability, while MIPs afford stronger recognition capability with higher selectivity and specificity. Most importantly, the developed sensor was validated for 17β-E2 detection in food samples with larger detection range from 1 × 10-12 to 1 × 10-5 and lower detection limit of 1 × 10-13. Therefore, such nanowell-based MIP electrochemical sensor may be a promising candidate electrochemical sensor for trace pollution detection in food samples.