UC San Diego

Over the last two decades, the field of electrochemical sensors has seen rapid growth in its functionality, accuracy, and miniaturization. There is a growing use of different nanostructures for enhancing the electrochemical detection, the integration of electrochemical sensing platforms with wearable bioelectronic technology, and multiplexed sensing with various biomarkers found in saliva, sweat, tears and ISF. The nanostructure of focus is microneedles, spread out on three different surfaces of electrodes: the working electrode, the reference electrode, and the counter electrode. These surfaces will consist of three main components that will be tested for electrochemical activity: the substrate roughness, the metallic coating, and the electrode layer interface thickness. This paper will be focusing on the interactions between the metallic coating adhesion between the layers to best optimize the performance and life of the sensor. Specifically, this paper will investigate different sputtered layer thicknesses of the electrode metals and its adhesion onto its PMMA or PLA substrate. This will be accomplished in three phases: cyclic voltammetry, physical adhesion promoters via the use of a 3D print and CNC machine, and sputtering methods and protocols to help determine coating breakdown and rate of immobilization.