Graphene oxide-based nanocomposites (GO-chitosan and GO-EDTA) for outstanding antimicrobial potential against some Candida species and pathogenic bacteria

Abstract

To obtain the synergistic antimicrobial potential of nano-composites conjugated with graphene oxide (GO), an alternative approach was developed throughout the hybridization of chitosan (CS) or ethylene diamine tetraacetic acid (EDTA) with GO. The synthesized GO-nanocomposites were identified by XRD, HRTEM, SEM, FTIR, Zeta potential, and Raman spectroscopy. The antimicrobial activity of GO, GO-CS, and GO-EDTA was investigated against some pathogenic bacteria and Candida sp. Results showed that nano-composites looked flattened and clear, with some lines and folds on the exterior part. SEM images show the basic morphology of GO which owns remarkable holes, crevasses, and indeclinable internal structure. GO-EDTA and GO-CS possess a promising antimicrobial activity against all pathogenic microbes. In-vitro ZOI result verified that they exhibited activity against Escherichia coli (22.0 mm for GO-EDTA and 11.0 mm for GO-CS), Staphylococcus aureus (15.0 mm for GO-EDTA and 10.0 mm for GO-CS) and Candida albicans (22.0 mm for GO-EDTA and 16.0 mm for GO-CS). Microbial cells may be ultimately-damaged when they interact with GO-based nanocomposites due to different mechanisms such as oxidative and membrane stress and wrapping isolation. This work provides revolutionary GO-nanocomposites for increasing the antimicrobial activity against some pathogenic microbes with a cost-effective and eco-friendly approach.

Keywords: Antimicrobial activity; Candida albicans and chitosan; GO-based nano-composites; Reaction mechanism.