Use of living systems for clinical diagnostics by monitoring volatile chemicals

Abstract

Volatile organic compounds (VOCs) emitted via exhaled breath and bodily fluids are indicative of a diseased state within the body and have the potential to be used as a diagnostic tool. The study of VOCs in disease detection is a concept that has seen excellent engineering progress recently, namely via developments of electronic noses that aim to replicate biological olfactory principles through cross-selective electrode arrays and sensors. However, there has yet to be an engineered device that can capture the full breadth, sensitivity, and versatility of biological olfaction. This review summarizes common principles in biological olfaction and provides an overview of recent techniques to incorporate living systems for VOC detection. We discuss the recent advances, strengths, and weaknesses of all three types of living systems-based disease detection approach, which include a) olfactory behavioral detection, b) bioelectronic noses and c) ‘cyborg’ biosensors for disease detection.