Chapter 6 - Types of monitoring biosensor signals

Abstract

Biosensors are devices that combine biorecognition elements (bioreceptors) and transducers for qualitative and quantitative analysis of a variety of targets (analytes). There are various types of biosensors depending on the biorecognition elements and transducers used in them. Biosensors convert biochemical signals into measurable physiochemical signals, which are proportional to the concentration of a particular target or set of targets. These signals can be monitored by direct and indirect detection methods. In a direct detection mode, no label is used for recognition, and the target is directly detected. In contrast, to detect a target in an indirect detection mode, a secondary labeled ligand is required. Direct detection modes are simple, fast, and cost-effective, whereas in indirect detection modes, a labeled secondary molecule is needed, and the detection is more complicated. In spite of this disadvantage, indirect detection modes are very sensitive and present lower detection limits than direct detection modes do.