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We believe that this design strategy as well as our RSF/HPAAm DN gel will provide a new route for achieving high performance RSF-based gels with new functionalities.Zwitterionic hydrogels, as highly hydrated and soft materials, have been considered as promising materials for wound dressing, due to their unique antifouling and mechanical properties. While the viscoelasticity and softness of zwitterionic hydrogels are hypothetically essential for creating adaptive cellular niches, the underlying mechanically regulated wound healing mechanism still remains elusive. To test this hypothesis, we fabricated zwitterionic poly(sulfobetaine methacrylate) (polySBMA) hydrogels with different elastic moduli prepared at different crosslinker contents, and then applied the hydrogels to full-thickness cutaneous wounds in mice. In vivo wound healing studies compared the mechanical cue-induced effects of soft and stiff polySBMA hydrogels on wound closure rates, granulation tissue formation and collagen deposition. Collective results showed that the softer and more viscoelastic hydrogels facilitated cell proliferation, granulation formation, collagen aggregation, and chondrogenic ECM deposition. Such high wound healing efficiency by the softer hydrogels is likely attributed to stress dissipation by expanding the cell proliferation, the up-regulation of blood vessel formation, and the enhanced polarization of M2/M1 macrophages, both of which would provide more oxygen and nutrients for cell proliferation and migration, leading to enhanced wound repair. This work not only reveals a mechanical property-wound healing relationship of zwitterionic polySBMA hydrogels, but also provides a promising candidate and strategy for the next-generation of wound dressings.To address the difficult challenge of realizing macroscopic supramolecular assembly (MSA) of high-modulus hydrogels, we propose a strategy of introducing a flexible spacing coating to improve the surface compliance for efficient MSA, which holds promise to develop versatile MSA methods for fabricating hydrogel-based tissue scaffolds, and to provide insight into the MSA mechanism.We report a simple and reliable approach to fabricate composite hydrogel sheets with spatially patterned regions of plasmonic gold nanoparticles using a combination of contact printing and diffusion-controlled galvanic replacement reaction. NSC 309132 molecular weight In response to near-infrared laser irradiation, the localized increase in temperature induced the controlled shape deformation of the composite hydrogels, due to the combined effect of photothermal heating of the loaded gold nanoparticles and the thermal responsiveness of the hydrogel matrix. The same hydrogel can be designed to exhibit different modes of shape deformation depending on the direction of light irradiation, which has rarely been reported previously. The composite hydrogels may find applications in biomedicine and soft robots.Self-shaping hydrogels have received increasing attention due to their promising applications in soft robotics and biomedical fields. Here we report the fabrication of photo- and thermo-responsive composite hydrogels with heterogeneous structures and corresponding programmed deformations under stimulation. These composite gels were developed by photolithographic polymerization to form patterned non-responsive polyacrylamide gels and then thermal polymerization to form responsive poly(N-isopropyl acrylamide) gels containing photo-thermal agents in the interspace between the preformed non-responsive gels. Upon heating or near-infrared (NIR) light irradiation, the composite hydrogels with heterogeneous structures showed programmed bending, folding, and twisting deformations. Localized actuation or step-wise deformations were achieved by selective or sequential irradiations of NIR light on the specific regions of the composite hydrogels. This strategy should be suitable for other photo-responsive hydrogels with potential applications in diverse fields.Molecular dynamics (MD) is currently one of the preferred techniques employed to understand hydrogelation processes for its ability to include large amounts of atoms in computational calculations, since substantial amounts of solvent molecules are involved in gel formation. MD studies have helped to rationalize experimental outcomes that in many occasions were not well understood based on experimental observations. Additionally, MD has been used to study changes in gel physical properties triggered by variations in reaction conditions or gelator structures. Changes in many physical properties were understood using MD, including molecular diffusion, hydrogel swelling and volume transitions. All the examples gathered in this review might help the reader to discover the current state of the art in MD studies carried out to study hydrogelation processes as well as the pioneering studies that paved the way to introduce MD in the field of gels.Self-healing is one of the most fundamental properties of living tissues that allows them to withstand repeated damage. Self-healing hydrogels, which can spontaneously recover themselves after being ruptured, result in enhanced lifetimes for materials and open up a fascinating direction in materials science. Host-guest interactions have been widely used in the construction of self-healing hydrogels. We have emphasized the preparation and biomedical applications of self-healing hydrogels assembled by host-guest interactions, focusing on hosts of cyclodextrins and cucurbit[n]urils with various guests and tailored structures. The applications of self-healing hydrogels in biomedical fields such as drug delivery, encapsulation of cells and tissue engineering and 3D printing as well as interfacial adhesion were also summarized. At the end of this review, we propose the current challenges and future perspectives in this developing area.Hydrogels have been applied across a wide range of biomedical applications due to their versatility, but more recently have garnered interest as materials in bioelectronics due to the capacity to tailor their mechanical and biological properties. Hydrogel coatings in particular have been used to impart softness at the bionic device interface, deliver therapeutics and control cell interactions through presentation of peptides and growth factors. Additionally, the use of dynamic hydrogel properties has been harnessed as shuttles for the implantation of flexible electrode arrays. In all of these applications, the hydrogel must be designed not only to provide the desired performance, but also have no unexpected impacts on the surrounding tissues, such as extensive swelling that can compress the cells at the interface. Appropriate selection and design of hydrogel systems for bioelectronics requires an understanding of the physical, chemical and biological properties of hydrogels as well as their structure-property relationships.