Fabrication and Characterization of PANI/Ag Nanocomposites Voltammetric Sensor for Foodborne Bacteria

Introduction: Foodborne diseases are caused by consuming contaminated foods and/or beverages. Methods: Traditional detection methods for foodborne bacteria are sluggish and laborious. In this study, room temperature voltammetric sensors with low cost, specific, rapid and easy detection were fabricated using Polyaniline (PANI) and silver (Ag) nanoparticles. PANI films were coated on to the Indium Tin Oxide (ITO) glass substrate using electrochemical deposition technique. PANI surface was modified using Ag nanoparticles prepared by reduction method as Ag is one of the most powerful disinfectants against microbes. Both surface electron microscopy (SEM), X-ray diffraction (XRD) technique revealed the presence of Ag nanoparticles in the composites. The peaks observed in Fourier Transform Infrared Spectroscopy (FTIR) and optical absorption spectra are characteristics to PANI/Ag nanocomposites. Results: The antibacterial activities of the PANI/Ag nanocomposites were evaluated against Escherichia coli (E. Coli) (NCIM 2065), Staphylococcus aureus (S. aureus) (NCIM 2079) and Bacillus cereus (B. cereus) (NCIM 2106) using disk diffusion method. The composites showed better antibacterial activity due to the presence of Ag in comparison to pure PANI films. Conclusion: The sensor current for composites was found to increase with the presence of all the microbes. The sensitivity of the sensor was higher for E. coli bacteria among the other bacterial strains.