Photonic double-network hydrogel dressings for antibacterial phototherapy and inflammation regulation in the general management of cutaneous regeneration.

The treatment of festering pathogenic bacteria-induced skin wounds with increased inflammation is an ongoing challenge. The traditional antibacterial photothermal therapy always results in localized hyperthermia (over 50 °C), which inevitably delays tissue recovery. To address this serious issue, we devise a novel photonic hydrogel by integrating urchin-like Bi2S3 nano-heterojunctions (nano-HJs) into double-network hydrogels for infected skin regeneration. The synergy of NIR-triggered heat and ROS enables the hydrogels to achieve a rapid germicidal efficacy against bacteria within 15 min at mild temperature (below 50 °C). In vitro cell analysis results revealed that the photonic hydrogels exhibit superior cytocompatibility even after NIR illumination. More importantly, an in vivo study demonstrated that the photonic hydrogel dressings have a robust ability of accelerating contagious full-thickness wound regeneration through debriding abscesses, eliminating pathogens, improving collagen deposition, promoting angiogenesis, and adjusting the inflammation state. This photonic hydrogel system provides a general management strategy for the remedy of infectious wounds, where the incorporation of nano-HJs endows the hydrogels with the photodisinfection ability; in addition, the multifunctional hydrogels alleviate the damage from overwhelming heat towards surrounding tissues during phototherapy and steer the inflammation during the process of tissue regeneration. Accordingly, this work highlights the promising application of the photonic hydrogels in conquering refractory pathogen-invaded infection.

MXene-Based Hydrogels Endow Polyetheretherketone with Effective Osteogenicity and Combined Treatment of Osteosarcoma and Bacterial Infection.

After an osteosarcoma resection, the risks of cancer recurrence, postoperative infection, and large bone loss still threaten patients' health. Conventional treatment relies on implanting orthopedic materials to fill bone defects after surgery, but it has no ability of destroying residual tumor cells and preventing bacterial invasion. To tackle this challenge, here, we develop a novel multifunctional implant (SP@MX/GelMA) that mainly consists of MXene nanosheets, gelatin methacrylate (GelMA) hydrogels, and bioinert sulfonated polyetheretherketone (SP) with the purpose of facilitating tumor cell death, combating pathogenic bacteria, and promoting osteogenicity. Because of the synergistic photothermal effects of MXene and polydopamine (pDA), osteosarcoma cells are effectively killed on the multifunctional coatings under 808 nm near-infrared (NIR) irradiation through thermal ablation. After loading tobramycin (TOB), the SP@MX-TOB/GelMA implants display robust antibacterial properties against Gram-negative/Gram-positive bacteria. More importantly, the multifunctional implants are demonstrated to have superior cytocompatibility and osteogenesis-promoting capability in terms of cell replication, spreading, alkaline phosphatase activity, calcium matrix mineralization, and in vivo osseointegration. Accordingly, such photothermally controlled multifunctional implants not only defeat osteosarcoma cells and bacteria but also intensify osteogenicity, which hold a greatly promising countermeasure for curing postoperative tissue lesion from an osteosarcoma excision.

Two-dimensional MXene/cobalt nanowire heterojunction for controlled drug delivery and chemo-photothermal therapy.

Two-dimensional (2D) MXene nanomaterials have explored as a great potential candidate for tumor therapy during recent decades, especially for photothermal therapeutic applications. However, MXene-based drug-carriers cannot be elaborately controlled in cancer therapy. To solve the problem, a heterostructured titanium carbide-cobalt nanowires (Ti3C2-CoNWs) nanocarrier is developed for synergetic anticancer with magnetic controlling ability, dual stimuli-responsive drug release, and chemo-photothermal therapy. The structure, drug loading/release behavior, magnetic controlling capacity, photothermal performance, and synergistic therapeutic efficiency of the Ti3C2-CoNWs nanocarrier heterojunction are investigated. The heterostructured Ti3C2-CoNWs nanocarrier exhibits excellent photothermal conversion efficiency under 808 nm laser irradiation and high drug loading ability (225.05%). The doxorubicin (DOX) release behavior can be triggered by acid pH value (4-6) or near-infrared (NIR) irradiation. The Ti3C2-CoNWs nanocarrier heterojunction with synergistic chemo-photothermal therapeutic effect exhibits strong lethality for cancer cells than that of chemotherapy or photothermal therapy (PTT) alone. Therefore, Ti3C2-CoNWs nanocarrier heterojunction will be a promising choice for improving the efficiency of cancer treatment.