Two-dimensional TiO nanosheets with photothermal effects for wound sterilization

Sprayable, thermosensitive hydrogels for promoting wound healing based on hollow, porous and pH-sensitive ZnO microspheres

A solvothermal method and the subsequent heat treatment process were developed to fabricate hollow ZnO particles with hierarchical pores on a large scale. The as-obtained hollow, porous ZnO microspheres with tunable sizes, high specific surface areas, pH sensitivity, antibacterial properties, and high adsorption capacities showed significant advantages for drug delivery. Sprayable hydrogels containing hollow, porous ZnO microspheres and curcumin nanoparticles (CNPs) were prepared to accelerate wound healing. The water-dispersed CNPs promoted both the migration of fibroblasts and angiogenesis and an aqueous solution of Pluronic F127 (a temperature-sensitive phase-change hydrogel material) was shown to be an effective choice for medical dressings. The experimental data suggest that hollow, porous ZnO microspheres can be loaded with additional CNPs to achieve continuous long-term therapeutic effects.

Synthesis, structure, theoretical calculation and antibacterial property of two novel Zn(II)/Ni(II) compounds based on 3, 5-dichlorosalicylaldehyde thiocarbamide ligand

Two new compounds namely [Zn(L1)phen]31 and Ni(L1)phen(MeOH) 2 (L1 = 3, 5-dichlorosalicylaldehyde thiosemicarbazone) were synthesized by the slow evaporation method at room temperature. The structure of ligand L1 was determined using 1H NMR and 13C NMR spectra. X-ray single crystal diffraction analysis revealed that compounds 1-2 can form 3D supramolecular network structures through π···π stacking and hydrogen bonding interactions. The DFT calculation shows that the coordination of ligand and metal is in good agreement with the experimental results. Hirshfeld surface analysis revealed that H…H and Cl…H interactions were the predominant interactions in compounds 1-2. Energy framework analysis indicated that dispersion energy played a dominant role in the energy composition of compounds 1-2. The inhibitory effects of compounds 1-2 against Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA) were tested using the paper disk diffusion method (1: E. coli: 18 mm, MRSA: 17 mm, 2: E. coli: 15 mm, MRSA: 16 mm). Ion releasing experiments were conducted to assess the ion release capacity of compounds 1-2 (Zn2+, 4 days, 38.33 µg/mL; Ni2+, 4 days, 29.12 µg/mL). Molecular docking demonstrated the interaction modes of compounds 1-2 with UDP-N-acetylenolpyruvoylglucosamine reductase (MurB) and dihydrofolate reductase (DHFR) in bacteria, involving hydrophobic, stacking, hydrogen bonding and halogen bonding interactions. The generation of reactive oxygen species (ROS) in bacteria under the presence of compounds 1-2 were evaluated using a fluorescent dye known as dichlorodihydrofluorescein diacetate (DCFH-DA). Potential antibacterial mechanisms of compounds 1-2 were proposed.

Recent Progress in antibacterial hydrogel coatings for targeting biofilm to prevent orthopedic implant-associated infections

The application of orthopedic implants for bone tissue reconstruction and functional restoration is crucial for patients with severe bone fractures and defects. However, the abiotic nature of orthopedic implants allows bacterial adhesion and colonization, leading to the formation of bacterial biofilms on the implant surface. This can result in implant failure and severe complications such as osteomyelitis and septic arthritis. The emergence of antibiotic-resistant bacteria and the limited efficacy of drugs against biofilms have increased the risk of orthopedic implant-associated infections (OIAI), necessitating the development of alternative therapeutics. In this regard, antibacterial hydrogels based on bacteria repelling, contact killing, drug delivery, or external assistance strategies have been extensively investigated for coating orthopedic implants through surface modification, offering a promising approach to target biofilm formation and prevent OIAI. This review provides an overview of recent advancements in the application of antibacterial hydrogel coatings for preventing OIAI by targeting biofilm formation. The topics covered include: (1) the mechanisms underlying OIAI occurrence and the role of biofilms in exacerbating OIAI development; (2) current strategies to impart anti-biofilm properties to hydrogel coatings and the mechanisms involved in treating OIAI. This article aims to summarize the progress in antibacterial hydrogel coatings for OIAI prevention, providing valuable insights and facilitating the development of prognostic markers for the design of effective antibacterial orthopedic implants.