Fabrication of Nontoxic Reduced Graphene Oxide Protein Nanoframework as Sustained Antimicrobial Coating for Biomedical Application

Abstract

Bacterial colonization on medical devices is a major concern in the healthcare industry. In the present study, we report synthesis of environmental sustainable reduced graphene oxide (rGO) on the large scale through biosynthetic route and its potential application for antibacterial coating on medical devices. HRTEM image depicts formation of graphene nanosheet, while DLS and ζ potential studies reveal that in aqueous medium the average hydrodynamic size and surface charge of rGO are 4410 ± 116 nm and -25.2 ± 3.2 mV, respectively. The Raman, FTIR, and XPS data suggest in situ conjugation of protein with rGO. The as-synthesized rGO protein nanoframework exhibits dose-dependent antibacterial activity and potential of killing of 94% of Escherichia coli when treated with 80 μg/mL of rGO for 4 h. The hemolytic and cytotoxicity studies demonstrate that rGO protein nanoframework is highly biocompatible at the same concentration showing significant antimicrobial properties. The rGO coated on the glass surface obtained through covalent bonding exhibits potent antibacterial activity. Antibacterial mechanism further demonstrates that rGO-protein nanoframework in dispersed state (rGO solution) exerts bactericidal effect through physical disruption accompanied by ROS-mediated biochemical responses. The rGO subsequently entering into the cytoplasm through the damaged membrane causes metabolic imbalance in the cells. In sharp contrast, physical damage of the cell membrane is the dominant antibacterial mechanism of rGO in the immobilized state (rGO coated glass). The obtained results help indepth understanding of the antibacterial mechanism of the biosynthesized rGO and a novel way to develop nontoxic antibacterial coating on medical devices to prevent bacterial infection.

Zn‐incorporation with graphene oxide on Ti substrates surface to improve osteogenic activity and inhibit bacterial adhesion

“…Numerous efforts devoted to clarify the antibacterial pathway of GO and its derivatives, including physical damage of the cell membrane and oxidative stress (production of ROS) (Chen et al, ; Choudhary et al, ; Shen et al, ). Notably, the mechanism of GO‐induced oxidative stress was most widely recognized (Chen et al, ).…”

Functionalized Graphene Derivatives: Antibacterial Properties and Cytotoxicity

“…Graphene, a single layer of sp 2 -hybridized carbon atoms arranged in a honeycomb two-dimensional (2-D) crystal lattice, exhibits excellent chemical-physical, biochemical [2], mechanical, and engineering properties, extremely useful for several applications in sensors [3] and optoelectronic devices [4], environmental monitoring tools [5], food quality control [6], and medical devices [7]. With particular regard to the fields of application that include food quality control and medicine field applications, the antibacterial features [8] and the biocompatibility properties toward the real matrixes (as food or normal human cell lines, organic tissue, and blood) represent a key point that nanomaterials must possess. There are several cases of study, described in literature by interesting review articles concerning the improved antibacterial activity [9] and the increased biocompatibility [10] properties, exhibited by the graphene derivatives.…”

Vertically Aligned Graphene Coating is Bactericidal and Prevents the Formation of Bacterial Biofilms

“…Depending on the application, as long as a predominantly vertical alignment of the flakes can be achieved on the surface, sufficient antibacterial effects can probably be attained with a simpler coating method. The potential of graphene in biomedicine is far from being fully realized, due to the unexplored potential risks linked to the use of graphene and its derivatives . Graphene flakes in solution mainly represent an environmental and health hazard associated with free diffusion.…”