An Overview of Chitosan-Based Composites Containing Silver or Zinc Oxide Nanoparticles: Antimicrobial and Antibacterial Properties, and Biomedical Perspectives

Chitosan-derived antibacterial and antifungal agents: a review of recent strategies for activity enhancement

Investigating silver- and gold-functionalized electrospun PHBV fibers as dual-action antimicrobial and immunomodulatory biomaterials

Electrospun poly-based fibers functionalized with silver and gold nanoparticles demonstrated an excellent balance of safety, cytocompatibility, and antibacterial performance, making them promising candidates for biomedical applications that require both inflammation control and antimicrobial protection.

Design of ZnO-Based Nanomaterials and Nanocomposites for Antibacterial Applications.

Additive enhancement of biodegradability and antibacterial performance in thermoplastic starch/chitosan films incorporating oregano essential oil and silver-zinc oxide nanoparticles.

This study presents a novel thermoplastic starch-chitosan composite film, enhanced with oregano essential oil and silver-zinc oxide (Ag-ZnO: 1%) nanoparticles, designed to overcome the limitations of conventional biopolymer packaging. The synergistic combination of these additives significantly improved mechanical strength (tensile strength: 72.86 to 98.72 MPa), stiffness (Young's modulus), and reduced water uptake by up to 25% compared to unmodified controls. Rigorous biodegradation tests under UV, soil, and aqueous conditions demonstrated accelerated environmental breakdown, with up to 39.53% weight loss after one month under UV exposure. Antimicrobial assays showed inhibitory activity against the tested microorganisms, with inhibition zones of 42 mm against Staphylococcus aureus and 33 mm against Escherichia coli. These results highlight the multifunctional advantages of integrating biopolymers, essential oils, and nanometallic agents, and support a rational strategy for developing sustainable food-packaging materials with improved physical, degradative, and antimicrobial performance.

SYNERGISTIC EFFECT OF CHITOSAN AND NANOCRYSTALLINE CELLULOSE ON THE ANTIMICROBIAL ACTIVITY OF ELECTROSPUN POLYLACTIC ACID (PLA) NANOFIBERS

Objective The world is accelerating to find alternative antimicrobial materials due to the rapid development of antibiotic-resistant bacteria. Electrospinning of polymeric nanofibers can provide an attractive platform of developing bioactive surfaces with improved antibacterial functionality. Purpose: The research aimed to determine how the molecular weight of chitosan as well as the incorporation of nanocrystalline cellulose (NCC) affected the morphology and antibacterial activity of polylactic acid (PLA)-based electrospun nanofibers. Methods: Nanofibers were prepared through needle electrospinning method.  The morphological properties of the prepared nanofibers were determined by the use of the scanning electron microscopy (SEM). PLA was blended with two molecular weights of chitosan (7.5kDa and 15 kDa) in 8.5wt% concentration with or without NCC in the concentration of 8.5 wt% as well. The ASTM E2149-13a dynamic contact method was used to assess the anti-bacterial action against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Results: Results showed that the low molecular weight chitosan (7.5 kDa) formed smooth and uniform nanofibers (average diameter =169-180 nm), and chitosan of high molecular weight (15 kDa) formed beads with less homogeneous structures. Formulations with chitosan showed good antibacterial properties with growth inhibition of most strains tested being complete or almost complete in 1 hour. When NCC was added, there was an improvement in the fiber morphology and an increase inits antibacterial activity, especially with the 7.5 kDa chitosan formulation, which is indicating a synergist effect. In comparison, PLA or PLA/NCC fibers in the absence of chitosan exhibited low or ineffective antibacterial activity. Conclusion: The optimized Cs/NCC/PLA nanofibers, especially the one that contained low molecular weight chitosan, had a smoother and more uniform nanofibers and high spectrum antibacterial activity. The combination of chitosan and NCC boosts surface activity and membrane disruption of bacteria, which points to the possibility of using these composite nanofibers in biomedical applications as wound dressings and antimicrobial coating.

Antibacterial chitosan/silver nanoparticles films for food packaging: A review.

Chitosan is a renewable, biodegradable, and film-forming polysaccharide with intrinsic antibacterial activity, making it a promising matrix for food packaging applications. The introduction of silver nanoparticles (AgNPs) can further enhance the antibacterial performance of chitosan films, thereby improving their effectiveness in food packaging applications. Nevertheless, the antibacterial activity of the fabricated chitosan/AgNPs films largely depends on the formation, dispersion, and availability of AgNPs within the chitosan matrix. This review summarizes recent progress in chitosan/AgNPs films, focusing on fabrication strategies, antibacterial activity, and food preservation applications. There are two major fabrication strategies for the preparation of chitosan/AgNPs films, such as the one-pot synthesis (AgNPs are directly formed in situ within the chitosan matrix) and the two-step synthesis (AgNPs are pre-synthesized and then blended with the chitosan matrix). The antibacterial activity of the chitosan/AgNPs films can be regulated by adjusting the relative content and particle size of the incorporated AgNPs. Chitosan/AgNPs films are currently being applied for various food packaging applications, such as fruits, meats, seafood, and bakery foods. Overall, this review can provide guidance for the controllable preparation of chitosan/AgNPs films and the optimization of their antibacterial activity, thereby laying the foundation for their development as active food packaging materials.