Advances in the use of functional composites of β-cyclodextrin in electrochemical sensors.

β-Cyclodextrin (β-CD) possess a hydrophobic inner cavity and a hydrophilic exterior surface. They exhibit excellent inclusion properties with the guest molecules that match cavity size, and β-CD-based materials drew widespread attention in electrochemical sensors. The hydroxy groups at the edge of the cavity can form hydrogen bonds and undergo electrostatic and dipole-dipole interactions with other molecules. This review (with 109 refs.) reveals β-CD-based detection mechanisms from the viewpoint of the size/shape-fit concept, and summarizes the current state of multiple electrochemical sensors based on the use of β-CD and functionalized β-CD such as carboxymethyl-β-CD, mono-(6-ethanediamine-6-deoxy)-β-CD, hydroxypropyl-β-CD, thio-β-cyclodextrin, and others. Graphical abstract Schematic diagram of cyclodextrin inclusion complex formation in aqueous solution, represents water molecules, represents guest molecule.