Mussel-inspired adhesive antioxidant antibacterial hemostatic composite hydrogel wound dressing via photo-polymerization for infected skin wound healing.

Mussel-inspired adhesive antioxidant antibacterial hemostatic composite hydrogel wound dressing via photo-polymerization for infected skin wound healing

Biomaterials capable of transmitting signals over longer distances than those in rigid electronics can open new opportunities for humanity by mimicking the way tissues propagate information. For seamless mirroring of the human body, they also have to display conformability to its curvilinear architecture, as well as, reproducing native-like mechanical and electrical properties combined with the ability to self-heal on demand like native organs and tissues. Along these lines, a multifunctional composite is developed by mixing silk fibroin and reduced graphene oxide. The material is coined "CareGum" and capitalizes on a phenolic glue to facilitate sacrificial and hierarchical hydrogen bonds. The hierarchal bonding scheme gives rise to high mechanical toughness, record-breaking elongation capacity of ≈25 000%, excellent conformability to arbitrary and complex surfaces, 3D printability, a tenfold increase in electrical conductivity, and a fourfold increase in Young's modulus compared to its pristine counterpart. By taking advantage of these unique properties, a durable and self-healing bionic glove is developed for hand gesture sensing and sign translation. Indeed, CareGum is a new advanced material with promising applications in fields like cyborganics, bionics, soft robotics, human-machine interfaces, 3D-printed electronics, and flexible bioelectronics.

The Manufacture of Unbreakable Bionics via Multifunctional and Self-Healing Silk-Graphene Hydrogels.

The objective of this study was to develop an effective, potential wound dressing, which was constructed with a composite hydrogel of poly(vinyl alcohol) (PVA), carboxymethyl chitosan (CMC) and tannic acid (TA) by cryogenic treatment and freeze-drying method. The as-prepared TA-crosslinked PVA/CMC hydrogels exhibited interconnected pore structure with the mean pore size of roughly 3.7 μm. We found that the compressive strength and stiffness of composite hydrogel increased when the TA component was introduced. However, the PVA/CMC-TA hydrogel possessed obviously lower swell property than that of the TA-free PVA/CMC hydrogel. We also found that the TA addition significantly improved the antibacterial capacity of the as-prepared hydrogel. Moreover, the inhibition zone test showed that the antibacterial activity of PVA/CMC-TA against S. aureus bacteria was greater than that against E. coli. The biological results indicated that the PVA/CMC-TA hydrogel exhibited good cytocompatibility to natural human dermal fibroblasts. In summary, our PVA/CMC-TA composite hydrogel exhibited promising mechanical and antibacterial properties, which showed great potential application as wound healing materials.

Mechanical and antibacterial properties of tannic acid-encapsulated carboxymethyl chitosan/polyvinyl alcohol hydrogels

https://doi.org/10.1016/j.bioactmat.2022.02.034

Multi-crosslinking hydrogels with robust bio-adhesion and pro-coagulant activity for first-aid hemostasis and infected wound healing

Tannic acid-reinforced methacrylated chitosan/methacrylated silk fibroin hydrogels with multifunctionality for accelerating wound healing.

For the fabrication of engineered tissue constructs by three-dimensional (3D) bioprinting technology, the cell viability will be significantly affected by the shear stress during extrusion process and the exposure of light for cross-linking. Microgels with independently controlled compartments were demonstrated to provide protection for cells encapsulation. Here, we proposed to prepare the core-shell structured microgels for cells encapsulation to prevent the cell damage from the shear stress in extrusion-based 3D printing processes. The core-shell structured microgels with core layer of type I collagen and shell layer of alginate were prepared using a one-step innovational microfluidics technology through a multichannel microfluidic device. In the microfluidic parameters, acetic acid concentration and flow rate ratios of water phase to oil phase were found to evidently affect the morphology of microgels and viability of encapsulated cells. Methacrylated silk fibroin (SilMA) and methacrylated gelatin (GelMA) were synthesized and blended with cell-laden microgels as bioinks to fabricate the 3D-printed constructs. The increasing content of SilMA would decrease the pore size and increase the compression property of SilMA/GelMA hydrogels. Importantly, the microgels-containing SilMA/GelMA construct ensure the improved cell proliferation as compared to the SilMA/GelMA counterpart. Furthermore, the in vivo experiments demonstrated that Microgels-15%SilMA/GelMA construct exhibited good biocompatibility and better bone formation performance compared with 15%SilMA/GelMA construct. Therefore, the strategy of preparing cell-laden microgels based on microfluidic technology to improve the survival rate of cells in the bioprinting process can be available and effective in development of tissue engineered constructs.

Ningwen Chai

Papers

Tannic acid-reinforced methacrylated chitosan/methacrylated silk fibroin hydrogels with multifunctionality for accelerating wound healing.

Construction of 3D printed constructs based on microfluidic microgel for bone regeneration