(Invited) Tailoring 2D Materials As Artificial Enzymes for Developing Electrochemical Biosensors

Abstract

There is a significant need for development of low-cost and portable diagnostics for non-invasive monitoring of biochemical markers. Among various biosensors, electrochemical sensors are at the forefront of point of care diagnostics, due to simple and real-time readout, low cost, high sensitivity, and portability, as evident from the dominance of enzymatic glucose sensors in the healthcare sector.(1) Despite their significant success, one of the main challenges with enzyme-based sensors is the limited (or none) choice of enzymes for analytes beyond glucose and their incompatibility with device engineering processes.(2)Over the past few years, there have been significant advances in flexible sensors, printed electronics, and wireless devices based on graphene and other 2D materials.(2–5) Being atomically thin, with high surface-to-volume ratio, 2D materials are extremely sensitive to surface perturbation, making them suitable for highly sensitive and selective electrochemical sensors. Moreover, their physical, electronic, and electrochemical properties can be modified via doping, defects, and heterostructures to enable new functionalities for biochemical sensing. We have recently made significant progress in developing non-enzymatic electrochemical sensors based on 2D materials and hybrids as ‘artificial enzymes’, with special focus on device scalability and ease of fabrication. In this regard, we have studied the role of substrate in material-analyte interface characteristic,(6) the effect of post-deposition low-temperature annealing of 2D inks on material-analyte interaction, and the importance of defect configuration in tuning the material-analyte band alignment.(7) In this talk, I will present our recent progress and undergoing research in this area.