Magnetic microactuator embedded electrochemical sensing platform towards on-demand sensor cleaning

Reliable, time-resolved detection of biochemical markers is critical for providing actionable healthcare data. Biosensors can track various clinically relevant biomarkers to inform clinicians to make data-driven decisions. However, the notorious effects of complex fluids limit the lifetime of biosensors by fouling the active sensing sites, hindering their long-term functionality. Biomaterials with passive antifouling capabilities have been developed to minimize the effects of biofouling. However, these attempts can only delay the unavoidable outcome of fouling accumulation, which still limits long-term device functionality. Here, we present a novel class of biosensor capable of self-clearing their sensing surface that can avoid and actively remove biofoulants from the electrode surfaces. The active anti-biofouling modality consists of an electrochemical sensing platform embedded with magnetic microactuators previously proven to disrupt protein attachment and blood clot formation. In this study, we characterize the static and dynamic mechanical responses of the torsional thin-film magnetic microactuators. We confirm its protein-clearing capabilities using fluorescent bovine serum albumin. To quantify the advantages of magnetic actuation using electrochemical techniques, we conducted cyclic voltammetry and electrochemical impedance spectroscopy experiments. We believe this work presents a pivotal step towards enabling a truly longitudinal and continuous monitoring of multiple analytes in complex in vivo environment for a truly personalized medicine.