A novel biosensing of histamine based on liquid crystal through dielectric and electro-optical approaches

Abstract

The effects of histamine on blood vessels play a key role in immune response at the time of physical damage or some allergic reaction. The prevalent measurement methods for the detection of histamine are amperometric and capacitive biosensor techniques. Here, we present an easy fabrication and optimization studies of a novel liquid crystal (LC) based biosensor capable of detecting histamine level. The proposed biosensor is based on the orientational transition of nematic LC (NLC), 4′-octyl-4-biphenylcarbonitrile by enzymatic reaction of biomolecules. The sensing mechanism is based on homeotropic-to-planar configurational change of long molecular axes of LC when diamine oxidase/histamine was immobilized on the pretreated glass substrate. The developed LC-based histamine biosensor provides a good optical and dielectric response at a detection limit of 20 mg/L–500 mg/L.