Synthesis of conducting molecularly imprinted polymer nanoparticles for estriol chemosensing
Dominik Korol, Anna Kisiel, Maciej Cieplak, Agata Michalska, Piyush Sindhu Sharma, Krzysztof Maksymiuk
Abstract
Herein, electrochemically active molecularly imprinted polypyrrole nanoparticles (PPy NPs) were synthesized with the aid of micelles. Iron(III) p-toluenesulfonate induced polymerization of pyrrole resulting in the imprinting of estriol in growing NPs. Two separate imprinted NPs were prepared with pristine and derivatized pyrrole monomers. Techniques such as scanning electron microscope (SEM), and transmission electron microscope (TEM), confirmed the synthesis of imprinted PPy NPs of ~60 nm in size. NPs prepared with pristine pyrrole showed an imprinting factor of 4.2, while NPs prepared with derivatized pyrrole showed no imprinting. The electrochemical-based transduction allowed for the determination of estriol in the concentration range of 0.5 to 5 µM and 10 to 100 µM with the 0.16 µM limit of detection (LOD). Furthermore, the selectivity of the MIP NP-coated electrode toward estriol and its structural analogs, namely β-estradiol and estrone, was satisfactory.