CHOLESTEROL BIOSENSOR: NON-ELECTROPHORETICALLY DEPOSITED NANO-STRUCTURED CONDUCTING POLYANILINE FILM

ABSTRACT

Conducting polymers have emerged as potential materials for the manufacture of biosensors due to their electrical conductivity, environmental stability, simple and controlled processibility, and biocompatibility. PANI is regarded as special within the conjugated polymer family of conducting polymers because of its straightforward and reversible acid/base doping/dedoping chemistry, which permits control over attributes including free volume, solubility, electrical conductivity, and optical activity. Since they combine the qualities of high surface area materials with low-dimensional organic conductors, NS-PANI (nanotubes, nanorods, and nanospheres) have attracted a lot of scientific attention recently. This is because they may be able to perform better in situations where a large interfacial area between PANI and its surroundings is required. For instance, NS-PANI has been shown to have higher sensitivity and a quicker reaction time than its typical bulk equivalent in biosensor applications. The highly sensitive modulation of electrical conductance/resistance of nano-structures caused by variations in the electrostatic charges from different molecules adsorbing on their surface, which results in the carriers being depleted or accumulating in the "bulk" of nanoscale dimension structures, is thought to be responsible for the observed high sensitivity.

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