MoS₂@PDA@Ag/PVA Hybrid Hydrogel with Excellent Light‐Responsive Antibacterial Activity and Enhanced Mechanical Properties for Wound Dressing

Abstract

Hydrogel is an ideal wound dressing material because of its 3D network structure, which is similar to that of the extracellular matrix. However, it is a challenge to design antibiotic-free hydrogels with both antibacterial activity and enhanced mechanical strength. In this study, a polyvinyl alcohol (PVA) hybrid hydrogel incorporated with molybdenum disulfide@polydopamine@silver (MoS 2 @PDA@Ag) is prepared for rapid killing of bacteria under irradiation with near-infrared (NIR) light. The interpenetration of MoS 2 -based nanoparticles and PVA molecular chain significantly improves the mechanical property of the hydrogel. The hydrogels demonstrate an excellent photothermal effect and antibacterial activity, and the photocatalytic properties are considerably enhanced by Ag doping. The hydrogel exhibits favorable antibacterial activity after irradiation with 808 nm NIR light for 15 min due to the synergistic effect of reactive oxygen species and hyperthermia. Meanwhile, in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay further demonstrated that all hydrogels are nontoxic when their effects are examined against mouse fibroblasts (L929) cells. In addition, the MoS 2 @PDA@Ag/PVA hydrogel can promote wound healing compared with the pure PVA hydrogel, demonstrating its significant potential in mitigating bacterial infection of wounds.

2D nanomaterial-based 3D network hydrogels for anti-infection therapy

“…101 Similarly, Tang's group prepared a MoS 2 @P-DA@Ag/PVA antibacterial hydrogel by freeze-thaw cycling, and the as-prepared hydrogel killed bacteria by PTT. 102 Fig. 9a indicates the self-healing ability of PSCMo hydrogels.…”

“…By combining PTT and PDT, MoS 2 can generate ROS and transform light into heat, and combination treatment of PTT and PDT produces more ROS. 102 In recent years, antibacterial hydrogels based on MoS 2 , including PDMoT, MoS 2 @CNT, MoS 2 @PDA@Ag/PVA, Ag 3 PO 4 /MoS 2 , CuS@MoS 2 , and CFMG hydrogels, were proven to produce ROS ( OH and O 2 ) after PTT stimulation. 48,49,85,100,102,132 In 2021, Fan's group reported that by combining PTT and PDT, the PVA/Dex/MoS 2 @TA/Fe nanozyme-anchored multifunctional hydrogel (PDMoT) group had a lower abundance of E. coli and S. aureus compared with that of the PVA/Dex (PD) and PVA/Dex/MoS 2 (PDMo) groups.…”

“…102 In recent years, antibacterial hydrogels based on MoS 2 , including PDMoT, MoS 2 @CNT, MoS 2 @PDA@Ag/PVA, Ag 3 PO 4 /MoS 2 , CuS@MoS 2 , and CFMG hydrogels, were proven to produce ROS ( OH and O 2 ) after PTT stimulation. 48,49,85,100,102,132 In 2021, Fan's group reported that by combining PTT and PDT, the PVA/Dex/MoS 2 @TA/Fe nanozyme-anchored multifunctional hydrogel (PDMoT) group had a lower abundance of E. coli and S. aureus compared with that of the PVA/Dex (PD) and PVA/Dex/MoS 2 (PDMo) groups. The PDMoT + H 2 O 2 + NIR indicated excellent antibacterial ability with an inhibition rate of nearly 100% against both E. coli and S. aureus, owing to the combined effects of the PODlike activity of MoS 2 @TA/Fe to generate OH, GSH loss, and the hyperthermia induced by MoS 2 @TA/Fe.…”

In situ light‐activated materials for skin wound healing and repair: A narrative review

“…Comparatively, an intermediate healing rate was observed with their hydrogel without irradiation, hydrogel alone, or hydrogel with nanosheets without irradiation 114 . Yan et al prepared a PVA hydrogel incorporating molybdenum disulfide (MoS 2 )‐polydopamine‐AgNPs (7.5 mg/mL), observing that MoS 2 and polydopamine enhanced the strength of their PVA hydrogels 110 . The authors investigated a mixed microbial wound infection model in Kunming mice, wherein both S. aureus and Escherichia coli were inoculated into full‐thickness wounds prior to application of their hydrogels followed by 15 min of 808‐nm in situ light activation 110 .…”

Peptide-Based Double-Network Hydrogels for Melanoma Treatment and Wound Healing Promotion

“…Owing to the good biocompatibility, biofunctional diversity, and responsiveness of peptide hydrogels, − the three-dimensional network of self-assembled peptide supramolecular structures, anticancer strategies involving peptide hydrogels have great potential, either as drug carriers or as anticancer drugs being delivered to target cancer cells. − Especially in the case of malignant melanoma, it would be perfect if the ACP hydrogels could serve as mechanically supportable surgical dressings for the direct treatment of tumors, preventing tumor recurrence, and promoting sizable wound healing following surgery. For large wounds or lesions near the joints, ACP hydrogels with superior mechanical properties such as tensile and mechanical stability are particularly needed to avoid the negative effects of movement. − Unfortunately, most current viscoelastic peptide hydrogels are too soft for the surgical dressing purpose. , Therefore, it is important to improve the mechanical properties of ACP hydrogels.…”