In-situ electrochemical synthesis of Ni/Ni(OH)2/molecularly imprinted polymer nanocomposite for high-performance glucose detection

Abstract

This study presents a novel non-enzymatic glucose sensor that synergistically combines the high catalytic activity of nickel hydroxide (Ni(OH)₂) with the selective recognition of molecularly imprinted polymers (MIPs). The sensors were fabricated through an entirely in-situ synthesis directly on the electrode, comprising electrodeposition and oxidation of Ni/Ni(OH)₂ nanoparticles and electropolymerization of a glucose-imprinted MIP layer using pyrrole and 3-aminophenyl boronic acid. The integrated MIP layer significantly enhanced selectivity against common interferents while amplifying glucose sensitivity. The resulting sensor demonstrated a high sensitivity of 1802 μA mM⁻¹ cm⁻² with a linear range from 0.04 to 2.6 mM. Notably, the sensor exhibited remarkable stability, retaining 97.2 % of its original sensitivity after 6 months of room-temperature storage. To extend the linear range, Nafion coatings at two concentrations were applied, achieving ranges up to 0.04–11.6 mM with adjusted sensitivities. This innovative approach, leveraging MIPs to provide selectivity to electrocatalytic nanomaterials, offers a promising strategy for developing high-performance non-enzymatic sensors for glucose and other biomolecules in diabetes monitoring and beyond.