CHAPTER 11: BIOSENSORS AND NANOBIOSENSORS

Biosensors, sensing systems that use biological recognition, physicochemical transduction, and companion instrumentation, have been widely used to analyze and quantify different analytes. The application of biological entities to develop selective sensors has grown exponentially since the late 1990s, and the worldwide biosensor industry is now worth billions of dollars and tens of thousands of papers have been published in the area. Biosensors can be applied in medicine, pharmacology, food and process control, environmental monitoring, defense, and security. The biggest market is in the medical area, particularly the glucose biosensors for people with diabetes. The latest trend is to apply biosensors for personalized medicine. The modification of electrode surfaces with biological molecules (enzymes, antibodies, nucleic acids, organelles, whole cells, tissues, etc.) has now evolved with the use of nanostructures. The emergence of nanotechnology promises to enhance the performance of biotransducers through interface engineering. Among the nano-enabled enhancements, we find preferential orientation of biomolecules onto device surfaces, improved bioelectrocatalytic performance, direct electron transfer, and the consequential increased sensitivity and miniaturization. Recently, it has been suggested that amyloids, a class of protein aggregates, originally associated with human diseases, could be used for the bio-nanotechnological applications, particularly in the development of biosensors.

This chapter introduces the concept of biomedical biosensors, discusses the various transduction principles, the various biological agents used in biorecognition, the engineering challenges in fabrication and systems applications, and the new frontier opportunities for both fabrication and applying biosensors.