Selective detection of estradiol using a molecularly imprinted self-assembled monolayer on gold surface

Abstract

Molecularly imprinted polymer (MIP) was synthesized to selectively detect estrogen-like chemicals depending on their shapes and binding characteristics to Estrogen Receptor (ER) active site. MIP was synthesized on self-assembled monolayer (SAM) formed by thiol-acrylate photopolymerization on Surface Plasmon Resonance (SPR) chip. The imprinting factor was calculated based on the shift of SPR angle at which the excitation of surface plasmons by light was minimum level. The imprinting factor, 4.3, was calculated by angle shift by SPR, which showed higher imprinting factor than the previous studies. We also validated the specificity of molecularly imprinted polymer loaded gold chip and compared the binding ability to estrogenicity known by in-vivo and in-vitro biological test. Molecular imprinting reflected the whole surface characteristics including three dimensional shape, types and location of functional groups, and distribution of interaction forces such as hydrogen bonding and van der Waals interaction. Therefore, MIP binding response could provide more insight on structure and estrogenic activity. Another purpose was to provide the basic data for future development of EDC screening array chip to find out various hormone activities at once.