From Sensors to Systems: CMOS-Integrated Electrochemical Biosensors

Novel electronic detection techniques are being increasingly sought as components of highly scalable technologies for high-throughput biosensing applications. Among the techniques being considered, electrochemical detection offers an attractive alternative. Advancement in nanoscale electrochemistry makes this an opportune moment to consider the prospects of its integration with CMOS processes. This paper focuses on the new properties and challenges that emerge from the downscaling of electrode dimensions, focusing, in particular, on redox-cycling-based approaches to nanoscale electrochemical devices. We explore the possibilities of interfacing arrays of such devices with CMOS process technology to create highly parallelized integrated platforms. We cite selective examples to provide a qualitative overview of the general design constraints that attend any system-level integration process. We also discuss several challenges that limit the scalability of such platforms and that need to be overcome to create reliable and robust CMOS-integrated electrochemical biosensing platforms.