Synthesis of silver nanoparticles using gallic acid-conjugated chitosan derivatives

•Different chitosan derivatives, containing covalently bonded gallic acid were synthesised and characterised.•AgNPs can be simply obtained at mild conditions by using chitosan derivatives as stabilizing and reducing agents.•New water soluble chitosan derivative can lower the cytotoxicity of AgNPs and increase its hemocompatibility and stability. In presented study, various chitosan derivatives containing covalently bounded gallic acid were obtained: chitosan with gallic acid (CG), quaternized chitosan with gallic acid (QCG), and succinylated chitosan with gallic acid (SCG). Chitosan derivatives were used as stabilizing and reducing agents in the synthesis of silver nanoparticles (AgNPs). The dimensional characteristics of nanomaterials were determined by transmission electron (TEM), dynamic light scattering (DLS) and atomic force (AFM) microscopy, antibacterial activity (against E. coli, S. epidermidis), cytotoxicity (HaCaT, Colo 357 cell lines) and hemocompatibility. Among all samples, QCG-AgNPs showed low toxicity in the range of studied concentrations (3.125−100 μg/ml) high stability of nanoparticle for 4 months (according to UV.spectroscopy data) the highest antibacterial activity against S. epidermidis (3.91 μg/ml). The high antibacterial activity, stability, and simplicity of the process of producing AgNPs based on the QCG derivative reveals that a new method for producing modified AgNPs deserves future consideration.