More natural more better: triple natural anti-oxidant puerarin/ferulic acid/polydopamine incorporated hydrogel for wound healing.

During wound healing, the overproduction of reactive oxygen species (ROS) can break the cellular oxidant/antioxidant balance, which prolongs healing. The wound dressings targeting the mitigation of ROS will be of great advantages for the wound healing. puerarin (PUE) and ferulic acid (FA) are natural compounds derived from herbs that exhibit multiple pharmacological activities, such as antioxidant and anti-inflammatory effects. Polydopamine (PDA) is made from natural dopamine and shows excellent antioxidant function. Therefore, the combination of natural antioxidants into hydrogel dressing is a promising therapy for wound healing. Hydrogel wound dressings have been developed by incorporating PUE or FA via PDA nanoparticles (NPs) into polyethylene glycol diacrylate (PEG-DA) hydrogel. This hydrogel can load natural antioxidant drugs and retain the drug in the gel network for a long period due to the presence of PDA NPs. Under oxidative stress, this hydrogel can improve the activity of superoxide dismutase and glutathione peroxidase and reduce the levels of ROS and malondialdehyde, thus preventing oxidative damage to cells, and then promoting wound healing, tissue regeneration, and collagen accumulation. Overall, this triple antioxidant hydrogel accelerates wound healing by alleviating oxidative injury. Our study thus provides a new way about co-delivery of multiple antioxidant natural molecules from herbs via antioxidant nanoparticles for wound healing and skin regeneration.

Ou Q ，Zhang S ，Fu C ，Yu L ，Xin P ，Gu Z ，Cao Z ，Wu J ，Wang Y ... -  《JOURNAL OF NANOBIOTECHNOLOGY》

Polydopamine/puerarin nanoparticle-incorporated hybrid hydrogels for enhanced wound healing.

Zhang S ，Ou Q ，Xin P ，Yuan Q ，Wang Y ，Wu J ... -  《-》

Reduced polydopamine nanoparticles incorporated oxidized dextran/chitosan hybrid hydrogels with enhanced antioxidative and antibacterial properties for accelerated wound healing.

Hydrogels with antioxidative and antibacterial properties have emerged as potential dressings for accelerated wound healing. Herein, a series of reduced polydopamine nanoparticles (rPDA NPs) incorporated oxidized dextran/chitosan hybrid hydrogels have been designed for wound healing due to their excellent antioxidative property and antibacterial activity. The physicochemical properties as well as the antioxidative activities of the hydrogels were carefully characterized. The results demonstrated rPDA NPs have better antioxidative activity than the untreated PDA NPs. And the rPDA NPs incorporated oxidized dextran/chitosan hybrid hydrogels had excellent antioxidative properties to protect cells against external oxidative stress. Besides, the hydrogels also showed antibacterial ability to protect the wound against infections. In vitro and in vivo investigations concluded that rPDA NPs incorporated oxidized dextran/chitosan hybrid hydrogels could be served as an effective dressing for accelerated wound healing.

Fu Y ，Zhang J ，Wang Y ，Li J ，Bao J ，Xu X ，Zhang C ，Li Y ，Wu H ，Gu Z ... -  《-》

"All-in-one" self-healing and injectable cationic guar gum hydrogel dressing functionalized by bioactive complexes composed of natural small molecules.

Reducing the risk of wound infection is an urgent issue health priority. Antibacterial polysaccharide-based hydrogels have attracted great attention for infectious wounds, attributed to their safe antimicrobial performance and natural non-toxicity and biodegradability advantages. In this study, the "all-in-one" self-adaptive and injectable cationic guar gum (CG)-based polysaccharide hydrogels (FA-TOB/CG) loaded with bioactive complexes were developed for infectious wound healing. The constructed antioxidant and antibacterial ferulic acid (FA)-tobramycin (TOB) bioactive complexes (FA-TOB) were used as the cross-linking agent and introduced into the CG matrix to construct the FA-TOB/CG hydrogel with a three-dimensional porous structure. The sterilization rates of FA-TOB/CG hydrogel against S. aureus and E. coli reached 98 % and 80 % respectively. In addition, the FA-TOB/CG also exhibits enhanced antioxidant performances (DPPH: > 40 %; ABTS: > 90 %; ·OH: > 50 %). More importantly, FA-TOB/CG hydrogel also showed the ability to sustain the release of FA and TOB. These superiorities of the FA-TOB/CG hydrogel enabled it to provide a moist wound environment and promote wound healing by eliminating bacteria, modulating the local inflammatory response, and accelerating collagen deposition and vascular regeneration. Thus, this study may enlarge a new sight for developing multifunctional dressings by incorporating bioactive complexes into polysaccharide hydrogels for infected wounds.

Wang Y ，Yang M ，Yang Z ，Jiao J ，Zhao Z ，Liu Y ... -  《-》

Study the effect of different concentrations of polydopamine as a secure and bioactive crosslinker on dual crosslinking of oxidized alginate and gelatin wound dressings.

Alginate hydrogels are commonly used in wound care due to their ability to maintain a moist environment, absorb fluids, and aid wound healing. However, their stability and mechanical properties can sometimes limit their effectiveness. This study explores a new approach by creating a dual network system of oxidized alginate and gelatin hydrogel crosslinked with polydopamine in a single step, with the goal of improving the mechanical properties of these hydrogels. The unique aspect of this research is the comprehensive examination of different polydopamine concentrations in dual crosslinking systems. First, alginate was modified with sodium periodate to create additional active groups on its backbone, and various polydopamine concentrations were then tested to assess their impact on the dual crosslinking network and hydrogel properties. The study involved a range of tests, including FTIR, H-NMR, SEM, gelation time, rheology, adhesion, antioxidant activity, swelling ratio, weight loss, drug release, and cell viability. The addition of polydopamine was found to enhance the crosslinking density (0.859 × 109 mol.cm-3). Additionally, the results indicated improvements in properties such as reduced weight loss, enhanced antioxidant and adhesive qualities, and better mechanical properties (2240 kPa). However, the optimal concentration of polydopamine must be determined to achieve the best properties for a wound dressing. Excessive polydopamine can increase the space between polymer chains, leading to a reduction in crosslinking density and storage modulus. Nevertheless, it can also increase the swelling ratio, degradation rate, pore size, porosity, antioxidant activity, and dopamine release. Therefore, identifying the optimal concentration for a functional hydrogel is crucial. Notably, the hydrogel containing 0.5 mg.mL-1 polydopamine exhibited outstanding cell viability (108 % on the third day), swelling capacity (480 %), storage modulus (2240 kPa), gelation time (3 min), antioxidant activity (42.27 %), and skin adherence (11 kPa), making it an optimal choice for advanced wound management. According to the findings, it is emphasized that the application of this particular hydrogel expedites wound healing, as indicated by wound closure and histological studies. ABBREVIATIONS.

Kashi M ，Nazarpak MH ，Nourmohammadi J ，Moztarzadeh F ... -  《-》