13: Biosensors

Biosensors are analytical devices that convert biological actions into electrical signals to quantify them. In this chapter, biosensors that make use of the specificity of biological processes are described, that is, the recognition of enzymes for their substrates or other ligands, antibodies for their antigens, lectins for carbohydrates and nucleic acids or peptide nucleic acids for their complementary sequences. Biosensor science is interdisciplinary, bringing together chemistry, physics, biology, electronics and engineering to solve real-world analytical problems such as the sudden great need to test for coronavirus in the 2020–21 pandemic.