Bacterial infection causes wound inflammation and makes angiogenesis difficult. It is urgent to develop effectively antibacterial and pro-vascularizing dressings for wound healing. The hydrogel is developed with pH-responsive drug-releasing microcarriers which were loaded with vascular endothelial growth factor (VEGF) that promotes angiogenesis and actively respond to wound pH for control and prolong VEGF release. The surfaces of the microcarriers were coated with polydopamine which can reduce the silver nanoparticles (AgNPs) in situ, and dynamically crosslink with the polyacrylamide, which forms a stable slow-release system with different release behavior for the VEGF and AgNPs. The hydrogel inhibited bacterial formation and accelerated wound healing. With the hydrogel dressing, 83.3% ± 4.29% of the wound heals at day 7, which is 40.9% ± 8.5% higher than the non-treatment group in defect infected model. The antibacterial properties of hydrogel down-regulate early inflammation-related cytokines, and the release of VEGF in the middle and late phases of wound healing in response to pH changes promotes angiogenesis and up-regulate the expression of angiogenesis-associated cytokine. The sequential release of antibacterial agents and pro-vascularizing agents in response to the change in wound microenvironmental cues facilitate temporally controlled therapy that suites the need of different wound healing phases. Collectively, the hydrogel loaded with multifunctional microcarriers that enable controlled release of AgNPs and VEGF is an effective system for treating infected wounds.

细菌感染会导致伤口发炎并使血管生成变得困难。迫切需要开发有效抗菌和促血管化的伤口愈合敷料。水凝胶采用 pH 响应药物释放微载体开发，这些微载体载有血管内皮生长因子 (VEGF)，可促进血管生成并积极响应伤口 pH 值以控制和延长 VEGF 释放。微载体表面涂有聚多巴胺，可原位还原银纳米粒子 (AgNPs)，并与聚丙烯酰胺动态交联，形成稳定的缓释系统，对 VEGF 和 AgNPs 具有不同的释放行为。水凝胶抑制细菌形成并加速伤口愈合。使用水凝胶敷料，83.3% ± 4.29% 的伤口在第 7 天愈合，即 40.9% ± 8。缺陷感染模型比非治疗组高5%。水凝胶的抗菌特性下调早期炎症相关细胞因子，在伤口愈合的中后期响应pH变化释放VEGF促进血管生成并上调血管生成相关细胞因子的表达。响应于伤口微环境线索的变化而顺序释放抗菌剂和促血管形成剂促进了适合不同伤口愈合阶段需要的时间控制疗法。总的来说，载有多功能微载体的水凝胶能够控制 AgNPs 和 VEGF 的释放，是治疗感染伤口的有效系统。水凝胶的抗菌特性下调早期炎症相关细胞因子，在伤口愈合的中后期响应pH变化释放VEGF促进血管生成并上调血管生成相关细胞因子的表达。响应于伤口微环境线索的变化而顺序释放抗菌剂和促血管形成剂促进了适合不同伤口愈合阶段需要的时间控制疗法。总的来说，载有多功能微载体的水凝胶能够控制 AgNPs 和 VEGF 的释放，是治疗感染伤口的有效系统。水凝胶的抗菌特性下调早期炎症相关细胞因子，在伤口愈合的中后期响应pH变化释放VEGF促进血管生成并上调血管生成相关细胞因子的表达。响应于伤口微环境线索的变化而顺序释放抗菌剂和促血管形成剂促进了适合不同伤口愈合阶段需要的时间控制疗法。总的来说，载有多功能微载体的水凝胶能够控制 AgNPs 和 VEGF 的释放，是治疗感染伤口的有效系统。并且在伤口愈合的中后期响应pH变化释放VEGF促进血管生成并上调血管生成相关细胞因子的表达。响应于伤口微环境线索的变化而顺序释放抗菌剂和促血管形成剂促进了适合不同伤口愈合阶段需要的时间控制疗法。总的来说，载有多功能微载体的水凝胶能够控制 AgNPs 和 VEGF 的释放，是治疗感染伤口的有效系统。并且在伤口愈合的中后期响应pH变化释放VEGF促进血管生成并上调血管生成相关细胞因子的表达。响应于伤口微环境线索的变化而顺序释放抗菌剂和促血管形成剂促进了适合不同伤口愈合阶段需要的时间控制疗法。总的来说，载有多功能微载体的水凝胶能够控制 AgNPs 和 VEGF 的释放，是治疗感染伤口的有效系统。响应于伤口微环境线索的变化而顺序释放抗菌剂和促血管形成剂促进了适合不同伤口愈合阶段需要的时间控制疗法。总的来说，载有多功能微载体的水凝胶能够控制 AgNPs 和 VEGF 的释放，是治疗感染伤口的有效系统。响应于伤口微环境线索的变化而顺序释放抗菌剂和促血管形成剂促进了适合不同伤口愈合阶段需要的时间控制疗法。总的来说，载有多功能微载体的水凝胶能够控制 AgNPs 和 VEGF 的释放，是治疗感染伤口的有效系统。