Nickel Oxide and Graphene Oxide Incorporated Molecular Imprinted Coatings for Electrochemical Recognition of Acetylcholine

Abstract

Herein, we synthesized molecular imprinted polymer (MIP) coatings containing nickel oxide (NiO) nanoparticles and graphene oxide (GO) for enhanced electrochemical recognition of acetylcholine. The preparation of NiO nanoparticles is carried out by polyol’s method whereas GO was made by modified Hummer’s scheme. Four different sensor coatings i.e., pristine-MIP, NiO-MIP, GO-MIP, and NiO-GO-MIP were prepared and integrated with screen-printed interdigital capacitors (IDCs), respectively for capacitive sensing of acetylcholine. Among all these sensor devices, NiO-GO-MIP layer coated IDC exhibited the highest capacitance shifts (ΔC) for acetylcholine. Additionally, the NiO-GO-MIP coated IDCs showed at least three times higher sensor response for acetylcholine as compared to dopamine and xanthine suggesting high selectivity of the receptor layer. It was noticed that the sensor response of two weeks old NiO-GO-MIP coated IDCs was similar to that of freshly coated IDCs which indicates that developed sensor coating is stable and robust that can be used for extended times without losing recognition performance.