Functionalization of gold nanospheres and nanorods by chitosan oligosaccharide derivatives

Researchers conducted a study to introduce two new polymers derived from chitosan oligosaccharides for the surface modification of gold nanospheres and nanorods. It was demonstrated that these biopolymers have multiple thiols or oleic acids and primary amine groups. The study demonstrated that the first biopolymer is suitable for complete ligand exchange, while the second biopolymer is useful for partial ligand exchange. It was observed that gold nanorods were sensitive to aggregation after a complete ligand exchange with the first biopolymer and that hydrophobic gold nanospheres were unstable after partial ligand exchange with the second biopolymer. It was also found that these characteristics led the hydrophobic gold nanospheres to be converted into hydrophilic nanoparticles through ligand exchange with the first biopolymer.