Practical applications usually require solid conductive hydrogels with outstanding mechanical stability for flexible energy storage devices. Herein, a synergistic strategy of acetic acid induction and salting-out is proposed to achieve strong and tough conductive poly(vinyl alcohol) (PVA) hydrogels for flexible solid-state supercapacitors. Acetic acid introduced into the PVA/dimethyl sulfoxide (DMSO) system robbed the hydrogen bonding sites of DMSO bound to the hydroxyl groups of PVA, further encouraging the restoration of intra/inter-chain hydrogen bonds of PVA to form an organic pre-gel. Immersion of the PVA pre-gel in salt solution triggers the salting-out process coupled with solvent exchange, facilitating the structural microdomain densification and homogenization, forming a densely cross-linking network and endowing the synergistic PVA hydrogel with splendid mechanical capabilities (strength of 9.06 MPa, 1763% fracture elongation, and toughness of 85.8 MJ m⁻³). Attributed to the incorporation of ions, the synergistic PVA hydrogel attains satisfactory ionic conductivity (18.02 mS cm⁻¹). The assembled supercapacitor based on synergistic PVA hydrogels and carbon cloth/polyaniline composite electrodes delivers a prominent areal-specific capacitance of 73.13 mF cm⁻² at 0.5 mA cm⁻² and can achieve stable output even under deformation. A practical and efficient avenue for constructing strong tough conductive hydrogels is developed in this work, which has great potential for use in energy storage devices.

In this work, we fabricated porphyrin-loaded shape memory polymer (SMP) film by cross-linking micellar particles prepared by co-assembly of porphyrin compounds and amphiphilic macromolecules formulated by copolymerization of 2-butoxy ethanol (BCS), methyl methacrylate (MMA), butyl acrylate (BA) acrylic acid (AA), and diacetone acrylamide (DAAM). The experimental results revealed that this film was able to respond to the red light in terms of photothermal effect enabled by the porphyrin filler. The photothermal-triggered shape memory behaviors of the film were further examined in detail. It was noteworthy that this material was expected to have potential applications in the biomedical field due to the excellent biocompatibility of the porphyrin filler and the red-light source, which was optimal and safe enough for biomedical treatment.

The recruitment of key cells to regeneration sites is a promising strategy to promote functional wound healing. Dermal fibroblasts exhibit a heterogeneous population of cells during homeostasis and in response to injury. Papillary fibroblasts play central regulatory roles in the regeneration of skin appendages during wound healing. Inspired by the phenomenon where bait for grass carp can attract grouped grass carps to a fishing spot soon, “Grass Carp Fishing” multifunctional hydrogels, that is, codelivery of an antibody of leucine-rich repeats and immunoglobulin-like domains 1 (Lrig1) on the surface of papillary fibroblasts and insulin-like growth factor 1 (IGF1) with recruitment function, can recruit papillary fibroblasts. In the experiments, carboxymethyl chitosan showed positive effects in promoting cell proliferation and neovascularization, while dopamine-grafted gelatin was effective in stabilizing the structure and prolonging the degradation time. The sustained release of Lrig1 antibodies and IGF1 from injectable self-healing multifunctional hydrogels persistently accelerated the migration and proliferation of Lrig1⁺ fibroblasts. The in vivo results from a full-thickness cutaneous wound model showed that injectable self-healing multifunctional hydrogel accelerated wound healing and skin regeneration through the recruitment of Lrig1⁺ papillary fibroblasts in wound tissue. Our findings reveal an injectable self-healing multifunctional hydrogel for regeneration, a promising approach to promoting skin wound healing.

Herein, we report a novel monocarboxylic acid induction strategy to construct tough and thermo-reversible PVA physical gels with high transparency.

Photothermally triggered shape memory polymer materials are usually prepared by dispersing photothermally responsive fillers or compounds into shape memory polymer matrixes through physical blending, while the migration and non-biodegradability of the fillers limit their potential applications (e.g., in the biomedical field). Here, we synthesized a new type of porphyrin-based amphiphilic random copolymer bearing a reactive moiety of carbonyl group by co-polymerizing methyl methacrylate (MMA), butyl acrylate (BA), diacetone acrylamide (DAAM), acrylic acid (AA) and double-bonded vinyl porphyrin monomers, followed by induced self-assembly in aqueous solution to give rise to amphiphilic random copolymer nanoparticles. The nanoparticles were further crosslinked by means of adipic dihydrazide (ADH) to fabricate the photothermally triggered one-component shape memory polymer material. Compared with the most-studied multi-phase/multi-component shape memory polymer materials, the porphyrin moiety, playing the role of a photo-to-heat converter, covalently bonded into the polymer structure would certainly make it more homogeneous and more stable in principle.