ABSTRACT
This work describes a facile fabrication of an efficient electrochemical sensor utilizing sonication-derived Galinstan nanoparticles (Galinstan NPs) interfaced to annealed dirhenium heptoxide (Re2O7) thin-film on Silicon (Si) for the quantitative detection of the most promising acute renal disease biomarker Neutrophil Gelatinase Associated Lipocalin (NGAL). Under optimized preconditions, the anti-NGAL antibodies were immobilized on the Galinstan NPs/Re2O7/Si electrode by carbodiimide crosslinking to detect NGAL. The composition, morphology, and structural properties of the electrode were elucidated by various physical characterizations. The sensor obtained a high sensitivity (0.018 µA-1ng-1ml-1, R2 = 0.99) in differential pulse voltammetry and a minimum detection limit (2.14 ng ml-1) in electrochemical impedance spectroscopy for a wide range of NGAL concentrations (25-650 ng ml-1) with high selectivity and stability. The intensified performance of the sensor was achieved by the summed-up electron transfer from the Re2O7 film to Galinstan NPs and Galinstan NPs to the electroactive reactants. Additionally, the outer 2D gallium oxide (Ga2O3) layer of Galinstan Nps enhanced the redox activities, whereas the metallic core contributed to the magnificent conductivity. The excellent recovery rates of the sensor for different concentrations of NGAL measured in commercial human serum by the standard addition method assured the feasibility of the sensor.