Persistent wound infections have been a therapeutic challenge for a long time. Current treatment approaches are mostly based on the delivery of antibiotics, but these are not effective for all infections. Here, we report the development of a sensitive pH-responsive hydrogel that can provide controlled, pH-triggered release of silver nanoparticles (AgNPs). This delivery system was designed to sense the environmental pH and trigger the release of AgNPs when the pH changes from acidic to alkaline, as occurs due to the presence of pathogenic bacteria in the wound. Our results show that the prepared hydrogel restricts the release of AgNPs at acidic pH (pH = 4) but substantially amplifies it at alkaline pH (pH = 7.4 and pH = 10). This indicates the potential use of the hydrogel for the on-demand release of Ag+ depending on the environmental pH. In vitro antibacterial studies demonstrated effective elimination of both Gram-negative and positive bacteria. Additionally, the effective antibacterial dose of Ag+ showed no toxicity towards mammalian skin cells. Collectively, this pH-responsive hydrogel presents potential as a promising new material for the treatment of infected wounds.

中文翻译：

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pH 响应“智能”水凝胶可将银纳米粒子控制输送至感染伤口


长期以来，持续性伤口感染一直是治疗的挑战。目前的治疗方法主要基于抗生素的输送，但这些方法并不是对所有感染都有效。在此，我们报告了一种敏感 pH 响应水凝胶的开发，该水凝胶可以提供可控的、pH 触发的银纳米粒子 (AgNP) 释放。该输送系统旨在感测环境 pH 值，并在 pH 值从酸性变为碱性时（由于伤口中存在病原菌而发生这种情况）触发 AgNP 的释放。我们的结果表明，制备的水凝胶在酸性 pH 值（pH = 4）下限制了 AgNP 的释放，但在碱性 pH 值（pH = 7.4 和 pH = 10）下显着增强了它的释放。这表明水凝胶可用于根据环境 pH 值按需释放 Ag+。体外抗菌研究表明可有效消除革兰氏阴性和阳性细菌。此外，有效抗菌剂量的Ag+对哺乳动物皮肤细胞没有显示出毒性。总的来说，这种 pH 响应性水凝胶具有作为治疗感染伤口的有前途的新材料的潜力。