Injectable scaffolds are of great interests for skin regeneration because they can fill irregularly shaped defects through minimally invasive surgical treatments. In this study, an injectable hydrogel from biopolymers is developed and its application as wound dressings is examined. Gelatin-based hydrogels were successfully prepared at body temperature upon blending with low content of gellan, and the synergetic effect on the gel formation was carefully characterized through rheological methods. The electrostatic complexation between gelatin and gellan was confirmed to contribute a continuous hydrogel network. The obtained blend hydrogel demonstrates remarkable shear-thinning and self-recovering properties. For antibacterial purpose, tannic acid was incorporated into the blend hydrogel. In addition, tannic acid-loaded blend hydrogel was verified to accelerate the wound healing on the mice model, significantly than the control groups. Thus, this paper presents a facile approach without chemical modification to construct injectable gelatin-based hydrogels, which have great potential as a wound dressing or tissue scaffold at body temperature.

Hydrogel electrolytes have spurred the development of flexible energy storage devices by endowing them with liquid-like ion transport and solidlike mechanical elasticity. However, traditional hydrogel electrolytes always lose these functions in climate change because the internal water undergoes freezing and/or dehydration. In this work, a flexible supercapacitor (OHEC) is assembled based on the organohydrogel electrolyte (OHE) and activated carbon electrode material. The OHE is composed of PAMPS/PAAm doublenetwork hydrogel soaked from 4 m LiCl/ethylene glycol and exhibits good conductivities (1.9 and 22.9 mS cm −1 at −20 and 25 °C, respectively). The OHEC exhibits broad temperature adaptability (from −20 to 80 °C) and extraordinary resistance to mechanical damage (above 100 kg crushing). The OHEC avoids the polarization at low temperatures and retains 77.8% capacitance retention after storage at −20 °C for 30 days. Without extra sealed packaging, the OHEC maintains remarkable cycling stability (only 8.7% capacitance decay after 10 000 cycles) and retains 77.3% capacitance at 80 °C after 56 h. The outstanding anti-drying performance and improved interfacial compatibility of OHEC account for the good durability in the hightemperature environments. Additionally, other salts (such as LiClO 4 , NaCl, and KCl) with favorable solubility in ethylene glycol can also serve in OHEs for wide temperature range supercapacitors.

A new solvent system (an ethylene glycol solution of LiCl) is designed to prepare a robust organohydrogel with high flexibility and conductivity across a wide temperature range.

Peroxide-decorated Ti3C2Tx plays a role as an initiator for free-radical polymerization and leads to new opportunities for intelligent optoelectronic devices.

Nanoencapsulation is a promising method to improve the bioavailability of tea polyphenol (TPP). In this work, we adopted a green process to develop a new kind of complex coacervation core micelles (C3Ms) based on biopolymers for efficient tea polyphenol delivery. First, gelatin-dextran conjugate was synthesized using Maillard reaction. Then the C3Ms were produced by mixing gelatin-dextran conjugate with TPP. Variable factors on the self-assembly of the C3Ms were investigated. Under optimal conditions, the obtained C3Ms are of nanosize (average 86 nm in diameter) with narrow distribution. The formation of the C3Ms is attributed to hydrophobic interaction and hydrogen bonding instead of electrostatic interaction. Transmission electron microscope (TEM) and scanning electron microscope (SEM) results showed that C3Ms have a spherical shape with core-shell structure. ζ-Potential measurement suggested that the core is composed of gelatin with TPP, whereas the shell is composed of dextran segments. The encapsulation efficiency of the C3Ms is pH-independent, but the loading capacity is controllable and as high as 360 wt % (weight/weight of protein). In addition, the C3Ms show sustained release of TPP in vitro. MTT assay revealed that the C3Ms have comparable or even stronger cytotoxicity against MCF-7 cells than free TPP.