Alginate-based composite sponge containing silver nanoparticles synthesized in situ

Silver-based biomaterials have been developed in a variety of bactericidal applications, especially for wound dressings. In this study, silver nanoparticles (AgNPs) were synthesized in a sodium alginate solution and then the composite sponge containing AgNPs was prepared from the nanocolloid solution. The alginate-stabilized AgNPs had the mean negative zeta potential of -52.5 mV, suggesting that the surface charge prevents the nanoparticles from aggregating through electrostatic repulsion. The alginate-AgNPs composite sponge had a highly enhanced antimicrobial activity compared to the alginate sponge. In spite of excellent cytocompatibility of the alginate sponge, the viability of the cell treated with the alginate-AgNPs composite sponge extract decreased to 86% of the control. The amount of proinflammatory cytokines released from macrophages treated with the alginate-AgNPs composite sponge was reduced. For the preparation of AgNPs-embedded composites, alginate can be a potential candidate stabilizing AgNPs and providing synergistic antimicrobial and antiinflammatory activities with AgNPs.