Developing Molecular Imprinted Layers As Electro-Analytical Probes for Dydrogesterone Determination

Dydrogesterone is a synthetic derivative of female sex hormone whose structure and pharmacological action is similar to progesterone. This drug is used in various conditions including lack of endogenous, hormone replacement therapy and others. The increasing use of dydrogesterone as synthetic hormone also demands its rapid and accurate analysis in biological as well as environmental bodies. In this perspective, we developed molecular imprinted polymer (MIPs) coatings as recognition element for electro-analytical determination of dydrogesterone. Imprinted polymers are synthesized by self-organization of monomer chains around template structure keeping high percentage of cross-linker. Dydrogesterone-imprinted polymer gel is synthesized by free radical polymerization taking methacrylic acid and methyl methacrylate (functional co-monomers), ethyleneglycol dimethacrylate (cross-linker) and dydrogesterone (template). The non-imprinted polymer layer was taken as control material i.e. synthesized using the same polymer composition without introducing template. Following spin coating method, the developed polymeric gel was integrated with interdigital electrodes (IDEs) i.e. patterned on printed circuit board. IDEs fabricated with imprinted as well as non-imprinted polymer layer, respectively were connected to impedance analyzer. The subsequent shift in capacitive values of imprinted and non-imprinted layers was determined respectively as function of dydrogesterone concentration. The shift in capacitive values for imprinted layer was higher than the non-imprinted one. As the imprinted layer offers geometrical as well as chemical adaptation sites and upon fitting in these cavities the charge transfer between two electrode fingers is reduced which results in higher capacitance shift. On the other hand, the non-imprinted layer lack such functionality and offer only non-specific binding thus, leads to lower capacitive shifts. These results suggest that imprinted layers integrated with IDEs can be suitably used for dydrogesterone determination in complex matrices.