What question did this study set out to answer?

The research aims to create a hydrogel that controls antimicrobial release and improves infection management by adapting to pH changes.

March 28, 2026Open Access

pH-gated antimicrobial hydrogel with conformational adaptation for precision therapeutic release

YKYoung-Jun KimChonnam National University SSS.O. ShinDankook University YLYesung LeeDankook University

Key Points

The research aims to create a hydrogel that controls antimicrobial release and improves infection management by adapting to pH changes.
Developed a pH-sensitive hydrogel using 1-vinyl imidazole and N-isopropylacrylamide
Performed experiments on bacterial infections using patient-derived oral biofilms
Evaluated effects on wound healing in skin infections with methicillin-resistant S. aureus
Conducted metagenomic profiling to assess microbiome shifts
Significantly reduced bacterial populations of S. mutans and S. aureus compared to controls
Maintained cytocompatibility with human fibroblasts
Achieved faster wound closure with reduced bacterial load in MRSA-infected models
Promoted a balanced microbial community by preserving health-associated taxa

Abstract

Abstract Precision antimicrobial delivery at infection sites is limited by uncontrolled drug leakage under physiological conditions and mechanical fragility under repeated loading. These limitations undermine therapeutic efficacy while imposing off-target toxicity. Here, we introduce a pH-gated antimicrobial hydrogel engineered to autonomously gate antimicrobial release through conformational switching at constant physiological temperature. By incorporating 1-vinyl imidazole (VIm) as a pH-sensitive comonomer into a mechanically reinforced N-isopropylacrylamide (NIPAAm)–1,4-divinyloxybutane (DVB) network, the resulting NIPAAm–DVB–VIm (NDV) hydrogel adopts a collapsed, low-permeability state at neutral pH that suppresses baseline silver fluoride (AgF) leakage, then undergoes protonation-driven network expansion under pathological acidification to accelerate drug transport without external stimulation. This molecular gating mechanism maintains cytocompatibility in human gingival fibroblasts while achieving pronounced log-scale bacterial reductions against S. mutans and S. aureus compared with non-responsive controls. We systematically evaluated microbiome shifts from dysbiosis toward a more balanced community state in a dental caries model established with patient-derived oral biofilms, where metagenomic profiling revealed that acidic eluates preferentially depleted cariogenic taxa while preserving health-associated commensals, thereby supporting microbiome rebalancing. We extended this microbiome-conscious infection-control strategy to methicillin-resistant S. aureus ( MRSA )-infected full-thickness skin wounds, where topical application of the hydrogel accelerated wound closure, reduced bacterial burden, dampened pro-inflammatory cytokine expression, and partially recovered microbial diversity toward a more balanced ecological state. By coupling pH-autonomous control with mechanical durability, this pH-gated NDV hydrogel provides a strategy for selective, microbiome-conscious infection management across oral and cutaneous pathologies.

اسأل الذكاء الاصطناعي

Bookmark

View Full Paper