Enhancing the Sensitivity of Needle-Implantable Electrochemical Glucose Sensors via Surface Rebuilding:

Objective:Needle-implantable sensors have shown to provide reliable continuous glucose monitoring for diabetes management. In order to reduce tissue injury during sensor implantation, there is a constant need for device size reduction, which imposes challenges in terms of sensitivity and reliability, as part of decreasing signal-to-noise and increasing layer complexity. Herein, we report sensitivity enhancement via electrochemical surface rebuilding of the working electrode (WE), which creates a three-dimensional nanoporous configuration with increased surface area.Methods:The gold WE was electrochemically rebuilt to render its surface nanoporous followed by decoration with platinum nanoparticles. The efficacy of such process was studied using sensor sensitivity against hydrogen peroxide (H2O2). For glucose detection, the WE was further coated with five layers, namely (1) polyphenol (2)glucose oxidase(3) polyurethane (4)catalase, and (5) dexamethasone-releasing poly(vinyl alcohol)/poly(lactic-co-glycolic ...