Fabrication of bacterial cellulose/polyaniline/single-walled carbon nanotubes membrane for potential application as biosensor.

Electrically conductive polymeric membranes of BC with polyaniline (PAni) were fabricated through ex situ oxidative polymerization. PAni was densely arrayed along BC fibers and SWCNTs were uniformly distributed in the composites as confirmed by field emission scanning electron microscopy (FE-SEM). Fourier transform-infrared (FT-IR) spectra of the composite membranes exhibited characteristic peaks for specific functional groups of PAni and SWCNTs besides BC. X-ray diffraction (XRD) analysis indicated the presence of specific peaks for BC, PAni, and SWCNTs in the composites. The conjugated backbone of PAni and SWCNTs contributed to improve the degradation temperatures from 232°C for BC to 260°C, 302°C, and 310°C for BC-PAni, BC-PAni/SWCNTs-I (0.05mg/mL), and BC-PAni/SWCNTs-II (0.1mg/mL) composites, respectively. The electrical conductivity of BC was enhanced to 1.04×10-3S/cm, 4.64×10-3S/cm, and 1.41×10-2S/cm upon doping with PAni, and 0.05mg/mL and 0.1mg/mL SWCNTs, respectively in dry state which was further increased to 4.02×10-2S/cm, 3.03×10-2S/cm, 5.93×10-1S/cm, and 7.36×10-1S/cm, respectively in PBS solution. These membranes can potentially be used for applications requiring biocompatibility and electrical conductivity such as biological and chemical sensors.