Crosslinking Chitosan with Silver-Sulfur Doped Graphene Quantum Dots: An Efficient Antibacterial Nanocomposite Hydrogel Films

Polysaccharides are among the most potent materials for wound dressing construction. In this study, antibacterial flexible hydrogel films were prepared through a novel crosslinking of biopolymeric chitosan (CS) with silver-sulfur doped graphene quantum dots (Ag@S-GQD). To end this, S-GQDs were first synthesized from citric acid and 3-mercaptopropionic acid via a direct pyrolysis method at 200 degrees C. Then, S-GQDs were used as a reducing agent for in-situ forming Ag nanoparticles toward the synthesizing Ag@S-GQD nanoparticles. They were incorporated within the biopolymeric CS matrix in different concentrations and hydrogel films were constructed via a simple casting method. Different techniques were considered to characterize and confirm the structure and properties of the constructed films. The results of the in-vitro cytotoxicity and antibacterial studies showed that the prepared nanocomposite, CS/Ag@S-GQD, has a good cytocompatibility toward Human skin fibroblast (HFF-1) cells (cell viability remained over similar to 90% even after 48 h of incubation) and considerable antibacterial activity against various gram-negative and positive bacterial strains (from 0.2 +/- 0.1 to 0.8 +/- 0.1 cm inhibition zone). The obtained results recommended this nanocomposite as a potential wound dressing. [GRAPHICS] .

Automated summary

In this study, antibacterial flexible hydrogel films were prepared by crosslinking biopolymer chitosan (CS) with silver-sulfur doped graphene quantum dots (Ag@S-GQD), which are among the most potent materials for wound dressing construction.