Ultrasonic vibration-assisted enhanced antibacterial activity of ZnO/ Chitosan bio-nanocomposite

This work delves into biopolymeric membrane-based piezo-catalyst and its effectiveness towards harmful gram positive (E. faecalis) and gram-negative (E. coli) pathogenic bacteria. Conventionally, piezo electric polymers and their modified nanocomposites have been used to eradicate pathogens by their functionality. Maybe first-time bio-compatible polymer (Chitosan) based nanocomposite (ZnO/Chitosan) has been used in this work. ZnO nanoparticle has been synthesized by hydrothermal technique and prepared hydrogel with Chitosan biopolymer. The nanoparticles and its modified counterparts have been characterized by conventional characterization techniques such as XRD, FTIR, FESEM, EDAX, TGA, UV-Vis, PL, Zeta potential etc. The structural assessment via X-Ray crystallography and FTIR validate the successful preparation of the nanocomposite. Electron microscopy, optical and thermal characterizations are used to probe the underlying physical insights of the specimen under study. A detailed examination also revealed that the catalytic process is accelerated by the production of reactive oxygen species particularly OH* during ultrasonic vibration, validated through Photoluminescence spectroscopy. This intriguing outcome led us to apply the piezo catalytic process-which has a drastic bactericidal impact (almost 96 % for E. faecalis and 98 % for E. coli killing after 20 min) and is developing as a substitute antibacterial method to eliminate pathogenic bacteria.