Composites Containing Fullerenes and Polysaccharides: Green and Facile Synthesis, Biocompatibility, and Antimicrobial Activity

By use of a green and simple ionic liquid, butylmethylimidazolium chloride (BMIm(+)Cl(-)) as a sole solvent, we developed a novel, green, and simple method to synthesize biocompatible composites containing polysaccharides (cellulose (CEL), chitosan (CS), and gamma-cyclodextrin (gamma-TCD)) and fullerene derivatives (amino-C-60 and hydroxy-C-60). The composites obtained (100%CEL, 100%CS, [CEL+gamma-TCD] and [CS+gamma-TCD]) readily adsorb amino-C-60 and hydroxy-C-60. Kinetics and adsorption isotherm results indicate that the fullerene derivatives physically adsorbed onto the surface of the CEL-based composites and subsequently desorbed from the composites when they were soaked in water. Conversely, because both fullerene derivatives strongly adsorbed onto the surface and subsequently diffused into the pores within the matrix of the CS-based composites, it was possible to synthesize (CS+amino-C-60), (CS+hydroxy-C-60), (CS +gamma-TCD+amino-C-60), and (CS+gamma-TCD+hydroxyl-C-60) composites. Microbial assay results show that adding gamma-TCD, amino-C-60, and/or hydroxyl-C-60 to CS substantially increases the composite's ability to reduce the growth of antibiotic-resistant bacteria such as Vancomycin-resistant Enterococcus (VRE). Biocompatibility assays indicate that hydroxy-C-60 and amino-Co are not cytotoxic to humans when encapsulated into CS composites. Taken together, the (CS+gamma-TCD+fullerene) composites are well suited for various applications ranging from dressing to treat chronically infected wounds to nonlinear optics, biosensors, and therapeutic agents.