Synthesis Characterization of Nanostructured Conducting Polymers NSCP and Application in Biosensors

Abstract

Synthesis of nanostructured conducting polymers (NSCPs) is an option to improve the processibility and conductivity of conducting polymers. A series of nanostructured conducting polyanilines (NSPANI) have been synthesized using single and composite structure directing agents (SDA). The structure directing agents include sodium dodecyl sulphonate (SDS), sodium dodecylbenzene sulphonate (SDBS) and camphor sulphonic acid (CSA). The NSPANI nanodispersions have been characterized by UV-visible, FTIR, TEM, Scanning electron microscopy (SEM), Dynamic light scattering(DLS), AFM. The glucose (based on glucose oxidase, GOx), hydrogen peroxide (based on horseradish peroxide, HRP) and cholesterol (based on cholesterol oxidase, ChOx) biosensors have been attempted based on the cast film (prepared from the best NSPANI (PANI2) and response studies have been conducted photometrically. To further enhance the electro catalytic activity and stability of NSPANI film, a nanocomposite dispersion (NSPANI-AuNP-GR) based on NSPANI (S1I2), gold nano particles (AuNP) and graphene nanosheets (GR) has been developed using insitu polymerization. The surface morphology, chemical structure, thermal stability and electroactivities of NSPANI-AuNP-GR nanocomposite have been investigated by UV-visible spectroscopy, Fourier transform Raman spectroscopy (FT-Raman), Thermo gravimetric analysis (TGA), Transmission electron spectroscopy (TEM), Scanning electron microscopy (SEM), Atomic force microscopy (AFM), X-ray diffraction (XRD) pattern and conductivity measurements. In this regard, the effect of multienzyme system along with electrodeposited nanocomposite film has been exploited to develop a cholesterol biosensor to get a synergistic effect. The developed cholesterol biosensor has also been found to be reusable, reliable, stable and highly sensitive and can be successfully tested on blood serum samples to evaluate the free cholesterol. newline