Charge‐Transfer Polymeric Hydrogels with Self‐Healing, Injectable, Thermosensitive, Adhesive, and Antibacterial Properties for Diabetic Wound Healing

Abstract

Charge transfer (CT) complexes are self‐assembled structures with a variety of attractive properties, but little is known about their performance in the construction of polymeric hydrogels. Herein, a series of hydrogels (CT‐hydrogels) with CT complex are designed and synthesized. The CT complex, consisting of pyranine derivative (sodium 8‐((4‐vinylbenzyl)oxy)pyrene‐1,3,6‐trisulfonate, VB‐HPTS) and viologen derivative (1‐methyl‐1′‐(4‐vinylbenzyl)‐[4,4′‐bipyridine]‐1,1′‐diium chloride iodide, VB‐MV), serves as the cross‐linker, and N‐(2‐hydroxyethyl)acrylamide is used as the backbone monomer. The CT complex allows CT‐hydrogels to have rapid self‐healing property, injectability, thermosensitivity, good adhesive strength on skin, and excellent antibacterial performance against both Gram‐negative and Gram‐positive bacteria. In addition, they have good biocompatibility and long‐term stability in both ambient and aqueous environments, showing potential application as wound dressing. Their performance in diabetic wound healing displays high wound healing rate, effectively inhibits inflammatory infiltration, and promotes neovascularization as compared with commercial wound dressings. The results of this study suggest that the multifunctional CT‐hydrogels are of great value in wound healing, and show a promising future to design hydrogels with CT complexes.

Bioinspired Polyacrylic Acid‐Based Dressing: Wet Adhesive, Self‐Healing, and Multi‐Biofunctional Coacervate Hydrogel Accelerates Wound Healing

“…Angiogenesis is another beneficial event for wound healing since new blood vessels can provide the necessary supply of nutrients and oxygen for tissue reconstruction and metabolic waste transport. [ 68 , 69 ] Immunofluorescence staining of CD31 was carried out to assess angiogenesis in the regenerated tissue (Figure 7D ). The red fluorescent signal (CD31) of the control group was the lowest.…”

Thermo-Chemical Cues-Mediated Strategy to Control Peptide Self-Assembly and Charge Transfer Complexation

“…Further, the fluorophore tethered peptide provides excellent opportunities for designing charge transfer (CT) complexes with high conductivity and charge carrier densities toward organic nanowires in electronic and optoelectronic nanodevices. − Typically, the low solubility of the CT components such as pyrene limits its formation in aqueous media and is known in solid-phase reactions or self-assembly in nonpolar solvents. There are some recent reports on CT interactions due to the encapsulation of fluorophores, morphological transitions, and organogels from pyrene, naphthalenediimide (NDI), or tetrathiafulvalene tethered peptides. − Recently, there have been efforts to form CT complexes in aqueous medium as the high charge mobility during the formation of the CT complex exhibits antimicrobial behavior, presumably due to the perturbation of the electrochemical potential of the bacterial cell membrane, leading to bacterial death. − Moreover, this may provide an alternative strategy to mitigate bacterial multidrug resistance, while the toxicity of the CT components to the normal cells remains a concern. In that regard, self-assembled peptide nanostructures incorporating the CT components are biocompatible and mitigate the solubility issues while retaining antimicrobial properties.…”

Viologen Cross-Linked Chitosan Hydrogel as Biobased Antiseptic Surface-Coating Materials

“…We have selected an alkylated quaternary pyridinium derivative, commonly known as viologen. − Viologen has been massively used owing to its multifaceted properties (ionic conductivity, photochromic and electrochromic properties, antibacterial properties, and so on). Its backbone has been included in dendrimers, polymers, and covalent organic framework, and more recently, it has been also embedded in hydrogels and/or grafted on other related nanostructures. − In most cases, these materials showed electro-sensitive properties ( e.g. , conductive hydrogels suitable for transdermal bioelectronics devices, wound dressing, electro-stimulated drug delivery, etc.)…”

“…, conductive hydrogels suitable for transdermal bioelectronics devices, wound dressing, electro-stimulated drug delivery, etc.) coupled to good antibacterial activity, with a more intriguing structure–reactivity relationship. ,,− ,− In a complementary fashion, mechanically tailorable double network chitosan-based hydrogels have also emerged as multitask functional biomaterials. − …”