(291c) Gold Leaf Electrodes for Affordable Biosensing

The COVID-19 pandemic illustrated the urgent need for rapid and sensitive point-of-care (POC) diagnostics. Electrochemical biosensors are ideal for POC diagnostics due to their sensitivity, portability and rapid turnaround times. Gold is a common substrate for electrochemical biosensors because it can readily be modified with thiolated biomolecules. However, the high cost of gold is prohibitively expensive, making it unsuitable for accessible and affordable POC tests. To make gold electrodes more accessible, we developed gold leaf electrodes that are affordable and can be made without any specialized equipment. The thinness of the gold leaf makes our electrodes nearly an order of magnitude cheaper than their commercially available counterparts; the purity of the gold leaf allows them to outperform their commercially available counterparts, which use dopants that interfere with assay performance. We have paired our gold leaf electrodes with CRISPR-based assays to detect multiple pathogens, including human papillomavirus (HPV) from clinical samples. In doing so, we have demonstrated that these electrodes are a platform technology that can be adapted to detect nearly any infectious disease.