Injectable Adhesive Self-Healing Multiple-Dynamic-Bond Crosslinked Hydrogel with Photothermal Antibacterial Activity for Infected Wound Healing

Abstract

The development of multifunctional injectable adhesive hydrogels with self-healing capacity, shape adaptability, on-demand removability, and excellent photothermal antibacterial activity to promote bacteria-infected wound healing is highly recommended in practical applications. In this work, an injectable adhesive self-healing multiple-dynamic-bond crosslinked hydrogel was formed by a multiple-dynamic-bond crosslinked network of dynamic borate/didiol interactions, hydrogen bonding, and Schiff base bond. The introduction of Mussel-inspired catechol groups into the hydrogels could endow tissues with adhesive properties, and the hydrogel could adhere well to the skin under water with good shape adaptability under bent and twisted states. The mechanical and adhesive properties improved through the introduction of borate/didiol interactions into the catechol-modified hydrogel with dynamic Schiff base crosslinking at low cost and easy preparation, and the adhesive hydrogel could be removed without second damage to the wound. Moreover, polydopamine nanoparticles (PDA NPs) were introduced into the hydrogels through Schiff base reactions between the quinone group on PDA NPs and the primary amine in glycol chitosan (GC), resulting in an efficient photothermal antibacterial activity with uniformly dispersed PDA NPs in the hydrogel. And the hydrogels illustrated good cytocompatibility and hemocompatibility. Finally, they could be injected to fully fill irregular wounds and significantly promote bacteria-infected wound healing by reducing the inflammatory response, accelerating collagen deposition, and promoting blood vessel reconstruction. Therefore, this demonstrated their superiority in serving as multifunctional dressings for treating a bacteria-infected wound.

A Metal Ion and Thermal-Responsive Bilayer Hydrogel Actuator Achieved by the Asymmetric Osmotic Flow of Water between Two Layers under Stimuli

“…The swelling behavior of the hydrogels [ 35 , 36 ] was measured in deionized water or metal ion solutions. Vacuum-dried samples were carefully weighed prior to immersion in deionized water, 0.6 mol/L NaCl aqueous solution, 0.6 mol/L CaCl 2 aqueous solution, 0.6 mol/L NiCl 2 aqueous solution, 0.6 mol/L AlCl 3 aqueous solution, 0.6 mol/L FeCl 3 aqueous solution, 0.6 mol/L CrCl 3 aqueous solution, and 0.6 mol/L CeCl 3 aqueous solution at room temperature.…”

Injectable Antibacterial Gelatin-Based Hydrogel Incorporated with Two-Dimensional Nanosheets for Multimodal Healing of Bacteria-Infected Wounds

“…Recently, photothermal therapy (PTT) has attracted great interest in the treatment of bacteria-accompanied wounds . Under near-infrared (NIR) light irradiation, a high local temperature (>50 °C) generated by the NIR-active wound dressing or nanosystem kills bacteria. , This is mainly due to physical damage (thermal destruction) to bacteria and on-demand drug release when an antimicrobial drug is used. Among the photothermally active materials, manganese dioxide (MnO 2 ) nanosheets intrinsically exhibited high photothermal conversion capability for highly efficient PTT .…”

“…Injectable hydrogels, with superior moisture retention capacity, biocompatibility, and wound exudate absorption characteristic, have been extensively used as the most attractive wound sealant with shape adaptability to cover asymmetric wounds. , Many drugs, antioxidants, photothermal/photodynamic agents, and hemostatic agents, can be loaded within 3-dimensional and porous structures using the dressings to accelerate wound healing processes in multiple aspects . The treatment of infected wounds with a single CDT, PTT, or gas therapy (GT) on the basis of hydrogels has been widely described; however, these monotherapies have significant limitations.…”

Dynamic reversible adhesives based on crosslinking network via Schiff base and Michael addition

“…26 Obviously, the choice of reaction substrate and the type of reaction chosen are important guidelines for the preparation of multifunctional adhesives. The preparation of multifunctional adhesives by Michael addition reaction [27][28][29][30][31] and Schiff base reaction [32][33][34][35][36] synthesis becomes an attractive solution.…”