Electrochemically Co-Deposited Au-Pt Bimetallic Nano-Clusters for Highly Catalytic Glucose Detection

Bimetallic nanoparticles (NPs) have been attention as attractive electrode materials owing to their unique and synergetic properties in many fields, especially in healthcare sensing platforms. Among them, Au-Pt bimetallic nano-clusters (NCs) are considered to be superior for their marked catalytic activity. We have confirmed this by comparing these bimetallic nanoclusters with dendritic Au (DenAu) NPs in glucose sensing applications.<br/>Since high standards like a broad range and a low limit of detection with utmost selectivity are primary concerns, the demand for materials with exceptional catalytic activity has been raised. Herein, we have fabricated the sensor by co-depositing the Au-Pt NCs onto the patterned seed Au layer at optimal agitation rates and applied potential, it was characterized by its properties (interfacial impedance, cyclic voltammogram, and response to the various glucose concentrations) compared to DenAu. During electrochemical deposition, the optimal growth conditions for Au-Pt NCs and DenAu were -0.1 V for 1000 sec (stirring rate of 1000 rpm) and -0.07 V for 400 sec, respectively, which were relatively low potential as well as fast deposition time.<br/>As a result, the sensor with Au-Pt NCs and DenAu showed remarkably high charge density yields of 309.21 μA/cm² and 73.74 μA/cm², respectively, while the sensor with plane Au electrode exhibited a charge density yield of 2.37 μA/cm². Moreover, they showed extremely enhanced interfacial impedance values of 1.3 kΩ (Au-Pt NCs), and 5.6 kΩ (DenAu) at 0.1Hz compared to that of 92.5 kΩ (plane Au) Consequently, Au-Pt NCs are considered to be an optimal candidate for the highly catalytic glucose detection.<br/>By virtue of the heightened catalytic activity of bimetallic NCs, our sensor with Au-Pt (NCs) could detect various concentrations of glucose at a wide range from 1 to 10000 μM without any use of a mediator. While considering the sensitivity and limit of detection (LOD), Au-Pt nano-clusters (NCs) exhibit exceptional sensitivity of 1715.46 μA m M^-1cm^-2and a very low limit of detection of 1.5 μM, comparably, DenAu shows 678μA m M^-1cm²sensitivity and 6 μM limit of detection.<br/>In the near future, the Au-Pt bimetallic nano-clusters (NCs) will be integrated into various sensing platforms (e.g., immuno-sensing, fuel-cell application, and electro-chromic system application, etc.), and their practical feasibility will be investigated.