Development, characterization and antimicrobial properties of silver nanoparticles loaded chitosan-alginate sponges for biomedical application

In this study chitosan/alginate (Ch/Alg) composite scaffolds were prepared using a freeze-drying method and loaded with various concentrations of silver nanoparticles (AgNPs). Structural, chemichal composition as well as biocompatibility and antibacterial properties were studied focused to biomedical application. Formation of polyelectrolyte complexes between chitosan and sodium alginate increases the mechanical resistance of the scaffold as well as porous morphology of the sample which is crucial for cell culture applications and results in the formation of a material characterized by good structural integrity. As-cast materials demonstrate high biocompatibility profile but AgNPs-loaded scaffold demonstrate minor cell inhibitory potencial. The early silver ion release during material degradation can affect cell viability, cell adhesion and proliferation. AgNPs in concentration of 6 × 10⁻⁵ g/mL significantly improves the antibacterial effect of sponges Alg/Ch/NaHCO₃ (2:2:1), Alg/Ch/NaHCO₃ (1:3:1) and Ch/NaHCO₃ (1:1) against Gram-negative bacteria. Graphic abstract: [Figure not available: see fulltext.]