Synthesis of viral-like lignin/Ag nanoparticles with spiky surfaces for antibacterial and antioxidant applications.

The components and engineered structures of nanomaterials significantly influence their properties and functionalities. Inspired by the effective interfacial interactions between natural viruses and host cells, we developed a novel virus-like lignin/silver (Ag) nanoparticle with a spiky surface designed for antibacterial and antioxidant therapies. This study comprehensively examined the antibacterial performance of these composite materials with different morphologies against E. coli and S. aureus. It is worth noting that their rough surfaces enhanced bacterial adhesion, and reduced the effective interaction distance between ROS, Ag+, and bacteria, thereby significantly enhancing the antimicrobial activity. In vitro, results demonstrate the minimum inhibitory concentrations of virus-like lignin/silver (Ag) nanoparticles against S. aureus (Gram-positive) and E. coli (Gram-negative) are 1.95 μg/mL and 3.9 μg/mL, respectively. According to the international standard ISO 2009 "Biological Evaluation of Medical Devices", F1-LNS@Ag-60 has higher biosafety compared to colloidal Ag NPs. Additionally, the radical clearance rate of F1-LNS@Ag-x for ABTS· + reaches 88.9 %, indicating substantial potential for wound dressing applications. Furthermore, evaluations of masks reveal that these nanoparticles can effectively eliminate bacteria on the mask surface within 30 min, highlighting their promising potential in personal protection. The concepts and design for modulating the structure of these virus-like nanoparticles hold considerable promise for developing novel, environmentally friendly, and highly efficient lignin-based antibacterial materials to address antibiotic overuse.