3.1.2.2. Chitosan-Based Electrochemical Nucleic Acid
Biosensors:
Chitosan-based DNA biosensors are formulated by surface fixing of
biotinylated probe DNA by its anionic phosphate to cationic amino group
of chitosan either by covalent bonding or affinity conjugation. This
sensor was used to detect Gonorrhea (a sexually transmitted illness), as
reported by Singh et al, (2011). Another application of chitosan-based
nucleic acid biosensor was used for detecting Salmonella typhi by
immobilizing ss DNA of infectious agent on graphene oxide/chitosan/ITO
nanocomposite (Singh et al., 2013). Complementary, noncomplementary, and
one base mismatch sequences may all be distinguished by the biosensor.
For the detection of E. coli 0157:H7, a comparable electrochemical DNA
biosensor was created by immobilizing SS E. coli DNA using a graphene
oxide chitosan hybrid nanocomposite (Xu et al., 2017).