Highly Stretchable, Adhesive, Biocompatible, and Antibacterial Hydrogel Dressings for Wound Healing

Abstract

Treatment of wounds in special areas is challenging due to inevitable movements and difficult fixation. Common cotton gauze suffers from incomplete joint surface coverage, confinement of joint movement, lack of antibacterial function, and frequent replacements. Hydrogels have been considered as good candidates for wound dressing because of their good flexibility and biocompatibility. Nevertheless, the adhesive, mechanical, and antibacterial properties of conventional hydrogels are not satisfactory. Herein, cationic polyelectrolyte brushes grafted from bacterial cellulose (BC) nanofibers are introduced into polydopamine/polyacrylamide hydrogels. The 1D polymer brushes have rigid BC backbones to enhance mechanical property of hydrogels, realizing high tensile strength (21–51 kPa), large tensile strain (899–1047%), and ideal compressive property. Positively charged quaternary ammonium groups of tethered polymer brushes provide long‐lasting antibacterial property to hydrogels and promote crawling and proliferation of negatively charged epidermis cells. Moreover, the hydrogels are rich in catechol groups and capable of adhering to various surfaces, meeting adhesive demand of large movement for special areas. With the above merits, the hydrogels demonstrate less inflammatory response and faster healing speed for in vivo wound healing on rats. Therefore, the multifunctional hydrogels show stable covering, little displacement, long‐lasting antibacteria, and fast wound healing, demonstrating promise in wound dressing.

Hydrogel tapes for fault-tolerant strong wet adhesion

“…After gradually forming covalent linkages, the hydrogel tapes show an increased adhesion strength of ~1268 J m -2 , outperforming many reported bioadhesives. [50][51][52][53][54][55] We further demonstrate the feasibility of using the hydrogel tapes as tissue sealants and adhesives for soft and implantable devices both in vitro and in vivo. Finally, we show that the hydrogel tapes are biocompatible, degradable and suitable for various biomedical applications.…”

Materials and Cytokines in the Healing of Diabetic Foot Ulcers

“…In addition to promise in treating excessive scarring, the generation of stretchable, adhesive dressings with inherent antibacterial activity can also be used to treat irregular, deformed, or dynamic surfaces. [ 177 ] Yang et al. developed a new hydrogel, containing both poly(diallyl dimethyl ammonium chloride) cationic bacterial cellulose and polydopamine/polyacrylamide, in which the presence of catechol groups promotes surface adhesion of the material, the cellulose component improves mechanical properties and quaternary ammonium groups increase antibacterial efficacy.…”

“…developed a new hydrogel, containing both poly(diallyl dimethyl ammonium chloride) cationic bacterial cellulose and polydopamine/polyacrylamide, in which the presence of catechol groups promotes surface adhesion of the material, the cellulose component improves mechanical properties and quaternary ammonium groups increase antibacterial efficacy. [ 177 ] This nanofibrous matrix shows both self‐healing and stretching (ten times its initial length), and can reversibly recover its original shape under compressive loading. [ 177 ] Impressively, this composite hydrogel can be directly adhered to glass, plastic, human or porcine skin, and could be successfully placed on dynamic surfaces such as bending joints with no retraction or rupture of the material, and no disruption of adherence during repeated stretching.…”

“…[ 177 ] This nanofibrous matrix shows both self‐healing and stretching (ten times its initial length), and can reversibly recover its original shape under compressive loading. [ 177 ] Impressively, this composite hydrogel can be directly adhered to glass, plastic, human or porcine skin, and could be successfully placed on dynamic surfaces such as bending joints with no retraction or rupture of the material, and no disruption of adherence during repeated stretching. [ 177 ] In an in vivo infected wound healing model, the authors noted their material promoted early wound closure, little inflammatory response, and stimulated collagen deposition.…”

“…[ 177 ] Impressively, this composite hydrogel can be directly adhered to glass, plastic, human or porcine skin, and could be successfully placed on dynamic surfaces such as bending joints with no retraction or rupture of the material, and no disruption of adherence during repeated stretching. [ 177 ] In an in vivo infected wound healing model, the authors noted their material promoted early wound closure, little inflammatory response, and stimulated collagen deposition. [ 177 ] This and similar types of multifunctional hydrogel dressings offer significant advantages as therapeutics to treat DFUs in dynamic and active areas, with open wound beds or exposed to contamination.…”