Flexible patch with printable and antibacterial conductive hydrogel electrodes for accelerated wound healing

doi:10.1016/j.biomaterials.2022.121479

Biomaterials

Volume 285, June 2022, 121479

https://doi.org/10.1016/j.biomaterials.2022.121479 Get rights and content

Abstract

Electrical stimulation can facilitate wound healing with high efficiency and limited side effects. However, current electrical stimulation devices have poor conformability with wounds due to their bulky nature and the rigidity of electrodes utilized. Here, a flexible electrical patch (ePatch) made with conductive hydrogel as electrodes to improve wound management was reported. The conductive hydrogel was synthesized using silver nanowire (AgNW) and methacrylated alginate (MAA), with the former chosen as the electrode material considering its antibacterial properties, and the latter used due to its clinical suitability in wound healing. The composition of the hydrogel was optimized to enable printing on medical-grade patches for personalized wound treatment. The ePatch was shown to promote re-epithelization, enhance angiogenesis, mediate immune response, and prevent infection development in the wound microenvironment. In vitro studies indicated an elevated secretion of growth factors with enhanced cell proliferation and migration ability in response to electrical stimulation. An in vivo study in the Sprague-Dawley rat model revealed a rapid wound closure within 7 days compared to 20 days of usual healing process in rodents.

Graphical abstract

A flexible electrical patch (ePatch) with conductive hydrogel was designed to accelerate wound healing. The conductive hydrogel contains silver nanowire and methacrylated alginate, which endow antibacterial efficacy and printability to the ePatch. Healing speed was promoted in a Sprague Dawley rat-based wound model.

Section snippets

Credit author statement

Canran Wang: Methodology, Investigation, Validation, Writing - Original Draft. Xing Jiang: Methodology, Investigation, Validation, Writing - Original Draft. Han-Jun Kim: Methodology, Investigation, Validation, Writing - Original Draft. Shiming Zhang: Methodology, Investigation. Xingwu Zhou: Investigation. Yi Chen: Investigation. Haonan Ling: Investigation. Yumeng Xu: Investigation. Zhaowei Chen: Investigation. Moyuan Qu: Investigation. Li Ren: Investigation. Jixiang Zhu: Investigation. Alberto

Preparation and characterization of AgNW-MAA ink

Conductive hydrogel has been investigated for a variety of medical applications. They are generally composed of conductive nanomaterials and organic binders [52]. In our study, MAA was chosen as the organic binder, and AgNW was selected as the conductive nanomaterial [53,54]. AgNWs and MAA were synthesized and characterized by scanning electron microscope (SEM) and nuclear magnetic resonance (NMR), respectively (Fig. S1, S2). As shown in Fig. S1, the synthesized AgNWs had a large

Conclusion

In summary, we have developed a flexible ePatch based on conductive hydrogel for accelerated wound healing. Conductive AgNW used in the hydrogel conferred antibacterial properties to the ePatch. Moreover, clinically used alginate hydrogel endowed the ePatch with good biocompatibility and printability. The double-crosslinked network enhanced the mechanical strength of the conductive hydrogel. By delivering EF to the wound, our ePatch was shown to boost the expression of growth factors by NIH 3T3

Materials

Polyvinylpyrrolidone (PVP360, Mw ≈ 360,000 g mol⁻¹), silver nitrate, sodium chloride, sodium alginate (A2033, medium viscosity), 2-Aminoethyl methacrylate hydrochloride (AEMA, 900,652), polydimethylsiloxane (PHR1518, PDMS) and calcium chloride (C1016) were purchased from Sigma-Aldrich. Fibronectin and polyimide tapes were supplied by Thermofisher Scientific.

Synthesis of the silver nanowire

AgNW was synthesized by reducing silver nitrate according to previous report. Briefly, 1 g of polyvinylpyrrolidone was mixed with 14 mg

Data availability

The experimental data required to reproduce the findings from this study will be made available to interested investigators upon request.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgment

The authors acknowledge funding from the National Institutes of Health (EB024403, EB023052, GM126831, and HL140618).

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¹: These authors contributed equally to this work.

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Flexible patch with printable and antibacterial conductive hydrogel electrodes for accelerated wound healing

Abstract

Graphical abstract

Section snippets

Credit author statement

Preparation and characterization of AgNW-MAA ink

Conclusion

Materials

Synthesis of the silver nanowire

Data availability

Declaration of competing interest

Acknowledgment

Chem. Eng. J.

Trends Biotechnol.

Am. J. Obstet. Gynecol.

Am. J. Surg.

Biosens. Bioelectron.

Trends Cell Biol.

Bioact. Mater.

Trends Immunol.

Trends Immunol.

J. Tissue Viability

Matter

NPG Asia Mater.

Adv. Drug Deliv. Rev.

Biomaterials

Int. J. Biol. Macromol.

J. Eur. Ceram. Soc.

Biotechnol. Adv.

Biochem. Biophys. Res. Commun.

Chem. Eng. J.

J. Pharmacol. Toxicol. Methods

J. Am. Col. Certif. Wound Spec.

Acute and impaired wound healing: pathophysiology and current methods for drug delivery, part 1: normal and chronic wounds: biology, causes, and approaches to care

Adv. Skin Wound Care

Negative pressure wound therapy for open traumatic wounds

Cochrane Database Syst. Rev.

Bioactive anti-inflammatory, antibacterial, antioxidative silicon-based nanofibrous dressing enables cutaneous tumor photothermo-chemo therapy and infection-induced wound healing

ACS Nano

Antimicrobial host defence peptides: functions and clinical potential

Nat. Rev. Drug Discov.

Challenges in the treatment of chronic wounds

Adv. Wound Care

Growth factors with enhanced syndecan binding generate tonic signalling and promote tissue healing

Nat. Biomed. Eng.

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Sci. Transl. Med.

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JAMA

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Sci. Adv.