Fabrication and characterization of Ag nanoparticle-embedded kappa-Carrageenan-Sodium alginate nanocomposite hydrogels with potential antibacterial and cytotoxic activities

Hydrogel nanocomposites are attracting increasing attention in field of biology owing to their unique properties. The present work focuses on the fabrication and characterization of novel hydrogel nanocomposite systems in which silver nanoparticles (AgNPs) are embedded in a carrageenan (kappa-CGN)-sodium alginate (SA) hydrogel. The performance of the prepared kappa-CGN-SA hydrogel and kappa-CGN-SA/AgNPs hydrogel nanocomposite was determined by UV-visible spectroscopy, FTIR, XRD, SEM, EDX spectrum, EDX mapping, and TEM analysis. Surface plasmon resonance at 428 nm confirmed the presence of AgNPs in the kappa-CGN-SA hydrogel. The results indicate that AgNPs with an average diameter of 30 nm were uniformly dispersed in the kappa-CGN-SA hydrogel matrix. The amount of Ag+ ion release kinetic from the kappa-CGN-SA hydrogel matrix is very low, showing that AgNPs were well trapped within the kappa-CGN-SA/AgNPs hydrogel nanocomposite. The high antibacterial activity of the kappa-CGN-SA/AgNPs hydrogel nanocomposite was found to be 89.6 +/- 1.4% and 91.4 +/- 2.3% against the gram-positive S. aureus and the gram-negative E. coli, respectively. Moreover, the kappa-CGN-SA/AgNPs hydrogel nanocomposite showed good biocompatibility by the MTT test. The novel kappa-CGN-SA/AgNPs hydrogel nanocomposite low cytotoxicity and antibacterial efficacy is proposed as a potential candidate for biomedical applications.