电活性水凝胶作为心肌组织工程的有希望的方法已经引起了广泛的兴趣。然而,时空特异性调节个体病理过程和实现无毒生物吸收的挑战仍然存在。在这里,受整个梗塞后病理过程的启发,通过反应性氧化物(ROS)敏感的二硫键和光敏交联反应,开发了一种可注射的导电生物可吸收黑磷纳米片(BPNS)负载的水凝胶(BHGD)。重要的是,按时间顺序编程的BHGD水凝胶可以在炎症过程中实现分级调节,增殖性,和心肌梗死(MI)的成熟期。更多细节,在早期梗塞期间,BHGD水凝胶能有效降低MI区的ROS水平,抑制细胞氧化应激损伤,并促进巨噬细胞M2极化,为受损心肌修复创造良好的环境。同时,ROS响应结构可以保护BPNS免受降解,并在MI微环境下保持良好的导电性。因此,BHGD水凝胶在MI区域具有组织匹配的模量和电导率,促进心肌细胞成熟和电信号交换,补偿受损的电信号,并在成熟期促进梗塞区的血管化。更重要的是,水凝胶的所有成分都降解为无毒物质,对重要器官没有不利影响。总的来说,所提出的负载BPNS的水凝胶为MI的临床治疗提供了可扩展且安全的选择.
Electroactive hydrogels have garnered extensive interest as a promising approach to myocardial tissue engineering. However, the challenges of spatiotemporal-specific modulation of individual pathological processes and achieving nontoxic bioresorption still remain. Herein, inspired by the entire postinfarct pathological processes, an injectable conductive bioresorbable black phosphorus nanosheets (BPNSs)-loaded hydrogel (BHGD) was developed via reactive oxide species (ROS)-sensitive disulfide-bridge and photomediated cross-linking reaction. Significantly, the chronologically programmed BHGD hydrogel can achieve graded modulation during the inflammatory, proliferative, and maturation phases of myocardial infarction (MI). More details, during early infarction, the BHGD hydrogel can effectively reduce ROS levels in the MI area, inhibit cellular oxidative stress damage, and promote macrophage M2 polarization, creating a favorable environment for damaged myocardium repair. Meanwhile, the ROS-responsive structure can protect BPNSs from degradation and maintain good conductivity under MI microenvironments. Therefore, the BHGD hydrogel possesses tissue-matched modulus and conductivity in the MI area, facilitating cardiomyocyte maturation and electrical signal exchange, compensating for impaired electrical signaling, and promoting vascularization in infarcted areas in the maturation phase. More importantly, all components of the hydrogel degrade into nontoxic substances without adverse effects on vital organs. Overall, the presented BPNS-loaded hydrogel offers an expandable and safe option for clinical treatment of MI.