Many applications proposed for functional nanofibers require their assembly into a monolithic cellular structure. The ability to maintain structural integrity upon large deformation is essential to ensure a macroscopic cellular material that functions reliably. However, it remains a great challenge to achieve high elasticity in three-dimensional (3D) nanofibrous networks. Here, we report a strategy to create fibrous, isotropically bonded elastic reconstructed (FIBER) aerogels with a hierarchical cellular structure and superelasticity by combining electrospun nanofibers and the freeze-shaping technique. Our approach allows the intrinsically lamellar deposited electrospun nanofibers to assemble into elastic bulk aerogels with tunable porous structure and wettability on a large scale. The resulting FIBER aerogels exhibit the integrated properties of ultralow density (<30 mg cm(-3)), rapid recovery from 80% compression strain, superhydrophobic-superoleophilic wettability, and high pore tortuosity. More interestingly, the FIBER aerogels can effectively separate surfactant-stabilized water-in-oil emulsions, solely using gravity, with high flux (maximum of 8140 ± 220 L m(-2) h(-1)) and high separation efficiency, which match well with the requirements for treating the real emulsions. The synthesis of FIBER aerogels also provides a versatile platform for exploring the applications of nanofibers in a self-supporting, structurally adaptive, and 3D macroscopic form.

Immediate hemorrhage control and anti-infection play important roles in the wound management. Besides, a moist environment is also beneficial for wound healing. Hydrogels are promising materials in urgent hemostasis and drug release. However, hydrogels have the disadvantage of rapid release profiles, leading to the exposure to high drug concentrations. In this study, we constructed hybrid hydrogels with rapid hemostasis and sustainable antibacterial property combining aminoethyl methacrylate hyaluronic acid (HA-AEMA) and methacrylated methoxy polyethylene glycol (mPEG-MA) hybrid hydrogels and chlorhexidine diacetate (CHX)-loaded nanogels. The CHX-loaded nanogels (CLNs) were prepared by the enzyme degradation of CHX-loaded lysine-based hydrogels. The HA-AEMA and mPEG-MA hybrid hydrogel loaded with CLNs (labeled as Gel@CLN) displayed a three-dimensional microporous structure and exhibited excellent swelling, mechanical property, and low cytotoxicity. The Gel@CLN hydrogel showed a prolonged release period of CHX over 240 h and the antibacterial property over 10 days. The hemostasis and wound-healing properties were evaluated in vivo using a mouse model. The results showed that hydrogel had the rapid hemostasis capacity and accelerated wound healing. In summary, CLN-loaded hydrogels may be excellent candidates as hemostasis and anti-infection materials for the wound dressing application.

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Developing permanent antibacterial and rapid hemostatic wound dressings with excellent biocompatibility is urgently needed and has always gained great attention. Here, a series of amino acid-derived pseudoprotein consisting of poly­(ester amide) (PEA)-based hydrogel dressings and three types of cationic short peptides (RGDK, RRRFK, and RRRFRGDK) are prepared. Compared with the antibacterial segments containing hydrogel scaffolds, the method of peptide modification of surface possesses the minimal usage of antibacterial moiety due to the effective contacting wound spots. Direct peptide RRRFRGDK (P3) conjugation to the hydrogel surface through an amidization reaction can enhance the antibacterial and hemostatic abilities with no or minimal outer appearance and inner morphology damage to the original hydrogels. The P3-functionalized hydrogel (Gel-g-P3) presents excellent water uptake capacity, robust mechanical strength, enzymatic biodegradation, good hemocompatibility, and cytocompatibility. Moreover, the Gel-g-P3 hydrogel has better adhesion capacities of blood cell and platelet and exhibits shorter hemostasis time in the mouse-liver injury model. Finally, the wound healing performance is evaluated in vivo using an infected wound model. The results show that the Gel-g-P3 hydrogel has accelerated the wound healing process, implying that the peptide-functionalized PEA-based hydrogels can be used as hemostasis agents and wound dressings for infected wounds.

Since bacterial infections seriously threaten human's health, considerable attention is devoted to the design of nanoscale antibacterial materials. Among them, metal nanoparticles cannot meet the requirements of durable antibacterial effects and are harmful to biological environments. In this study, environmentally friendly nanogels with durable antibacterial and antiadhesion properties are prepared by copolymerization of styrene, polycaprolactone‐hydroxyethyl methacrylate, and polyhexamethylene guanidine hydrochloride methacrylate. The resultant nanogels possess regular spherical morphologies with the size of about 200 nm. The nanogels exhibit a strong ability to kill bacteria and the mechanism is different from that of conventional antibacterial agent loaded nanoparticles. In addition, anti‐infection experiments explored by a wound model confirm the nanogels have the capability to prevent infection. Furthermore, the nanogels grafted on the surface of cotton fibers display good thermal stability, which is essential for finishing of fabrics. The cotton fabrics finished with nanogels can prevent the adhesion of bacteria by enhancing the hydrophobicity and the bacteriostatic rate. The antibacterial fabrics against Staphylococcus aureus and Escherichia coli are still more than 86% active after 50 times of mechanical washing. The biocompatible nanogels are unleachable from the antibacterial fabrics which demonstrate that they are ideal candidates for durable and environmental‐friendly nanoscaled antimicrobial materials.

A well-defined six-armed star triblock copolymer s-(PDEA62-b-PMMA195-b-PPEGMA47)6 was synthesized by the core-first ATRP method. The star triblock copolymer shows pH-tunable self-assembly behavior. Interestingly, the reversible vesicle–micelle transition could be achieved by simply adjusting the surrounding pH.

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A multifunctional composite filter combined with nanocrystalline MnO2 and a PE/PP bicomponent fiber by introducing corona charge technology has been fabricated and exhibited excellent filtration, adsorption and catalytic abilities in air pollutant abatement.