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Leather with durable and broad-spectrum antimicrobial properties is very attractive in applications to produce diabetic shoes. In this work, gallic acid stabilized silver nanoparticles (GA@AgNPs) were prepared as waterborne finishing agent to be spray-coated on leather surface, with subsequent immobilization onto skin collagen via chromium(III) cross-linking. Such chemical anchoring of AgNPs onto microscaled collagen fibers not only enhanced the hydrophobicity of leather surface but also converted the surface ζ-potential from a positive charge to a negative charge, resulting in the excellent microbial antiadhesive ability of GA@AgNP-coated leather because of its dual-hydrophobic and electrostatic repelling of microbial adhesion. Such GA@AgNP coating also exhibited broad-spectrum antimicrobial activity against Escherichia coli, Staphylococcus aureus, methicillin-resistant S. aureus, and Candida albicans, with killing efficiencies all higher than 99%. Moreover, the killed microbes could be easily released from this anionic GA@AgNP spray coating by simply washing, preserving, and giving long-term antimicrobial activity to leather products. Most of all, the robust immobilization of AgNPs guaranteed the durably antimicrobial activity of such GA@AgNP-coated leather against laundry, perspiration, and mechanical abrasion in real daily use.

Bacterial contamination of cotton dressing can potentially cause wound infection. To solve this problem, stable and uniform decoration of silver nanoparticles (AgNPs) onto cotton fabrics is a promising strategy to endow antibacterial activity to prevent wound infection. Herein, a facile codeposition of polydopamine (PDA)/polyethyleneimine (PEI) was performed on cotton fabrics for uniformly cross-linking gallic acid (GA)-stabilized silver nanoparticles (GA@AgNPs) via Michael addition and hydrogen bonding interactions. The as-prepared GA@AgNPs/PDA–PEI-coated cotton fabrics possessed a negatively charged surface because of the high-density GA on AgNPs, showing low cytotoxicity, hemocompatibility, and hemostatic ability. Because of its stable, uniform, and anionic interface composed of GA@AgNPs, this GA@AgNPs/PDA–PEI coating could effectively resist bacterial adhesion by electrostatic repulsion and also kill the attached bacteria through sustained Ag+ release, exhibiting strong, broad-spectrum, and durable antibacterial activities toward bacteria. Therefore, these GA@AgNPs/PDA–PEI-coated cotton fabrics show great potential for clinical application as antibacterial wound dressings.

The development of biocompatible advanced Fenton-like catalysts with high catalytic activity, good stability, and recyclability using sustainable biosourced materials is of considerable interest yet remains a challenge. Herein, we develop a novel mussel-inspired magnetic cellulose nanocomposite (MCNF/PDA) with carboxylated cellulose nanofibers (CNF) and explore as advanced Fenton-like catalysts to effectively degrade organic dyes and antibiotics. The MCNF/PDA nanocomposites were prepared by anchoring Fe3O4 nanoparticles to CNFs via chemical deposition followed with PDA coatings. The composites exhibit an excellent degradation activity toward methylene blue (MB) in a wide pH range of 2–10 in the presence of H2O2 and have a maximum degradation capacity of 2265 mg/g. Moreover, the MCNF/PDA nanocatalysts are highly stable and can be easily regenerated. After four cycles, it can still achieve the removal rate as high as 95%. In addition, the MCNF/PDA nanocatalysts also demonstrate an excellent degradation performance to the antibiotic tetracycline. This work provides new insights into fabricating biocompatible cellulosic-based advanced Fenton catalysts with sustainable biomass-derived materials to efficiently remove organic pollutants from wastewater.