Injectable Double‐Crosslinked Adhesive Hydrogels with High Mechanical Resilience and Effective Energy Dissipation for Joint Wound Treatment

Abstract

Due to the moist environment and inevitable movement, efficient wound closure and healing of vulnerable joint skin remains a great challenge. Herein, a poly(γ‐glutamic acid)‐crosslinked amino‐functionalized PEGylated poly(glycerol sebacate) (γ‐PGA/PEGS‐NH2) adhesive hydrogel is reported. PEGS‐NH2 and γ‐PGA not only forms covalent amide bonds with biological tissue surfaces to achieve strong moist adhesion but also establishes a stable chemically crosslinked network in bulk hydrogels to resist deformation. Furthermore, bioinspired gallic acid‐modified chitosan (CS‐GA) is introduced to enhance moist adhesion via multiple hydrogen bonds and establish a dynamic physically crosslinked network to dissipate energy. Consequently, this adhesive hydrogel strongly adheres to moist biological tissue, showing an adhesion six times higher than that of fibrin glue and comparable to that of strong cyanoacrylate glue. Moreover, benefiting from high mechanical resilience and effective energy dissipation, 200 cycles of loading–unloading mechanical tests conducted under an adhesive state and a full‐thickness rat skin incision model applied on a dynamic nape further confirmed the desirable dynamic tissue adhesion and wound healing performance. Combining the above ideal features with their good injectability and shape‐adaptability to complex contours, such adhesive hydrogels are demonstrated to be promising candidates for joint wound closure and healing in moist and dynamic physiological environment.

Tough, Instant, and Repeatable Adhesion of Self‐Healable Elastomers to Diverse Soft and Hard Surfaces

“…For the lap‐shear test, the sample was cut into a 20 × 20 mm 2 square with a thickness of 10 mm, and the testing velocity was 10 mm min −1 . The adhesion strength ( τ s ) was defined as the maximum tensile force ( F max ) per nominal contact area as τ s = F max / wl , [ 58 , 59 ] where w and l are the width and length of the contact area, respectively. The corresponding energy release rate was calculated as G = ( F/w ) 2 /(4 Eh ), [ 47 ] where E , h , and w are the elastic modulus, thickness, and width of elastomers, respectively.…”

A starch-regulated adhesive hydrogel dressing with controllable separation properties for painless dressing change

“…Since hydrogel dressings may experience more frequent movement at the joints, hydrogels need to have good mechanical properties. 35 The mechanical properties of HAVS hydrogels were quantified with both tensile and compressive testing at room temperature. The HAVS-0 hydrogel without MAS showed satisfying mechanical properties with 0.07 MPa rupture stress and 540% strain at rupture, which was mainly formed by hydrogen bonding and electrostatic interactions between the polymer molecular chains.…”

“…Good adhesive properties are necessary for a hydrogel dressing, which helps to immobilize and protect the wound. 35 However, a hydrogel dressing with a strong adhesive force can easily cause secondary damage to the wound in the process of replacement, because it is not easy to separate from the wound. Therefore, the preparation of hydrogel dressings with controllable separation properties has great significance in the application of wound dressings.…”

An Overview on Recent Progress of the Hydrogels: From Material Resources, Properties, to Functional Applications

“…[46] Additionally, by reducing diffusion of matrix metal precursors in the solution, metal nanoparticles can also be loaded in the preparation of hydrogels. [47][48][49] Hydrogel nanocomposite materials consists of polymer hydrogels and organic nanoparticles embedded in the hydrogel matrixes, [48,[50][51][52][53] which have attracted great attention owing to their distinctive inorganic and organic hybrid structures and the excellent mechanical properties in aspects of elasticity, [54,55] toughness, [56][57][58] viscosity, [59,60] and so on. In the process of hydrogels (the conversion of low viscosity solution to hydrogels), technologies such as microfluidic are allowed to prepare hydrogels with arbitrary geometry.…”