Green Synthesis of Chitosan-Coated Silver Nanoparticles (Ch-AgNPs): Harnessing Nature for Sustainable and Safe Nanomaterial Production

Abstract

The production of silver nanoparticles (AgNPs) using green synthesis methods promotes the use of environmentally friendly materials and facilitates a more sustainable production process by reducing environmental impact. In addition, combining the metal nanoparticles with biopolymers are getting important to enhance the safety profiles of formulations to determine the biological activities. With this concept, AgNPs were synthesized by green synthesis method from Betula spp. tree branches as reported previously by us and in current study, synthesized AgNPs were coated by one of biopolymer. Herein, Chitosan was used as capping and stabilizing agent. Characterization of the biosynthesized silver nanoparticles (AgNPs) and Chitosan coated silver nanoparticles (Ch-AgNPs) were evaluated with various techniques. Through this analysis, it was elucidated that the phenolic compounds present in Betula extract and Chitosan played dual roles as both reducing and capping agents, facilitating the formation of Ch-AgNPs. Particular size analysis by dynamic light scattering (DLS) and scanning electron microscopy (SEM) indicated that the Ch-AgNPs ranged from 49 to 118 nm in size, with a narrow size distribution. X-Ray Differentiation (XRD) patterns confirmed the high crystallinity of the resulting particles. Fourier transform infrared (FTIR) analysis further supported these findings, revealing the involvement of phenolic compound extracts in both the formation and stabilization of AgNPs. Additionally, FTIR confirmed the surface modification of AgNPs by chitosan. The efficiency of surface modified Ch-AgNPs was compared with uncoated AgNPs for their antimicrobial activity, antiproliferative efficiency and biocompatibility. Cell culture studies demonstrated that AgNPs were less toxic to L929 cells while maintaining effective cytotoxicity against HT-29 cells. Moreover, surface modification with chitosan enhanced the toxicity of AgNPs against HT-29 cells Furthermore, the first synthesized and evaluated Ch-AgNPs with this study from Betula extract, exhibited potent antimicrobial activity against both Gram-positive and Gram-negative bacteria. Our findings indicate that novel synthesized Ch-AgNPs formula may present a biocompatible and safety approach for further anticancer and antimicrobial studies.