(Invited) Barcode-Based Biorecognition for Electrochemical and Photoelectrochemical Biosensing

Biosensors are devices that combine biorecognition with signal transduction to analyze biologically-relevant targets. In order for these devices to be used in disease management, clinical decision making, and health monitoring, they must deliver sufficient sensitivity, specificity, and speed at the point-of-care and rely on minimal sample processing. This work is focused on developing integrated biorecognition and signal transduction strategies for enhancing the performance metrics of biosensors. Barcode-based biorecognition systems translate analyte capture to the release of specific signal transducing barcodes. We have focused on developing barcode-based systems that are compatible with photoelectrochemical and electrochemical readout for targeting proteins and nucleic acids. These systems translate molecular recognition elements using functional nucleic acids and antibody-DNA complexes for releasing an electroactive or a photoelectrochemical DNA barcode. We have combined these barcode-based systems with nanostructured electrochemical transducers for increased signal-to-noise-ratio and sensitivity. By combining barcode-based biorecognition with electrochemical readout, we have developed handheld biosensors for clinical analysis of urinary tract infections. We have also used these strategies for detecting prostate cancer biomarkers. Integration of barcode-based biorecognition with photoelectrochemical readout presents a new modality for biosensing and opens the route for ultrasensitive and programmable biosensing.