Antibacterial hydrogels for skin infected wounds: frontier approaches as antibiotic alternatives therapy

Skin wound infections are common and clinically challenging. Conventional antibiotic therapies are increasingly ineffective because of escalating bacterial resistance, highlighting the urgent need for alternative treatment strategies. Antibacterial hydrogels, multifunctional polymeric materials that integrate moisturizing, drug delivery, controlled release, and wound-healing properties, have emerged as highly promising candidates for managing infected wounds. Based on their underlying antimicrobial mechanisms, these systems can be broadly classified into three main categories: chemical, physical, and biological antibacterial hydrogels, which achieve bactericidal efficacy through drug release, physical disruption, or modulation of the host microenvironment and immune responses, respectively. Of tremendous significance is the advent of stimuli-responsive intelligent hydrogels, which provides new opportunities for achieving precise and efficient antibacterial therapy. This review systematically summarizes the material selection, design strategies, and representative advances in antibacterial hydrogels, with particular emphasis on their core mechanisms, strengths, and limitations, aiming to offer theoretical foundations and research perspectives for the rational optimization and clinical translation of next-generation antibacterial hydrogels.