CONDUCTING POLYMER BASED SENSOR EMBEDDED WITH BIMETALLIC Ni-Ag FOR DETECTION OF E. Coli IN WATER

Abstract

Conducting polymers can be suitable materials for microbe sensor because of the intrinsically conducting characteristic. Polyaniline (PANI) is found to be the most promising conducting polymer. The nanocomposite of PANI and bimetallic Ni-Ag was synthesized via sol-gel method. PANI-Ni-Ag thin films were deposited onto glass substrate using spin-coating technique. The films were characterized using XRD, AFM, TEM and UV-Vis spectroscopy. The performance of the sensor was conducted using I V measurement to obtain the changes in the current before and after the exposure to E. coli bacteria in water. The peaks in XRD pattern confirmed the presence of Ni and Ag crystallite in face-centered cubic structures. AFM images indicate the increase of PANI- Ni-Ag surface roughness films while the concentration of Ni increased. TEM image shows the spherical silver and nickel nanoparticles. The resonance plasma band from UV-Vis spectroscopy is located at around 472 nm to 484 nm. I–V measurements show that the presence of E. coli has increased the current change of the films. From the sensitivity performance, the increase of Ag concentration in the samples has increased the sensitivity of the sensor.