Abstract

The infections and delayed wound healing after cesarean delivery is one of the most complicated issues in surgical medicinal field. In the present investigation, designed novel polysialic acid loaded gelatin (PSA-Gel) composite hydrogels cross-linked by tannic acid (TA) has been developed and used as a facile wound dressing to improve cesarean wound healing ability with prevent bactericidal infections. The cross-linking effect was predominant when the TA content was lower, resulting in the formation of a cross-linked network. An effective TA cross-linking effect on the PSA-Gel hydrogel matrix was achieved when the amount of TA was around 15 wt %. The morphology of as-fabricated hydrogels was characterized using scanning electron microscopy (SEM) with an average pore sizes of PSA-Gel, PSA-Gel-TA-5%, PSA-Gel-TA-10%, and PSA-Gel-TA-15% hydrogels were 95.4 ± 12.6 μm, 120.4 ± 8.2 μm, 165.3 ± 21.6 μm, and 270.2 ± 32.5 μm, respectively. The effects of hydrogels on the swelling ratio, in vitro degradation, and mechanical properties were systemically evaluated. The TA cross-linked PSA-Gel hydrogels display strong antimicrobial behavior against gram-positive (Staphylococcus aureus) gram-negative (Escherichia coli) bacteria strains. Moreover, PSA-Gel-TA hydrogels also displayed favorable cytotoxicity toward L929 fibroblast cell lines. Finally, the therapeutic and wound healing potential of the PSA-Gel-TA hydrogels has been studied in vivo using the excision wound model in rats. The results indicate that the PSA-Gel-TA hydrogels have a greater and significant effect on wound closure and increased the wound healing rate compared with native PSA-Gel hydrogels and untreated control group at 94%, 73% and 65% on day 21. The findings suggest that PSA-Gel-TA hydrogels are promising dressing materials for the treatment of wound healing.

摘要

剖宫产术后感染和伤口愈合延迟是外科医学领域最复杂的问题之一。在本研究中，设计的新型单宁酸（TA）交联的聚唾液酸明胶（PSA-Gel）复合水凝胶已被开发并用作简便的伤口敷料，以提高剖宫产伤口愈合能力并防止细菌感染。当 TA 含量较低时，交联效应占主导地位，导致形成交联网络。当 TA 的量约为 15 wt% 时，实现了对 PSA-Gel 水凝胶基质的有效 TA 交联效果。使用扫描电子显微镜 (SEM) 表征制造的水凝胶的形态，平均孔径为 PSA-Gel、PSA-Gel-TA-5%、PSA-Gel-TA-10%、和 PSA-Gel-TA-15% 水凝胶分别为 95.4 ± 12.6 μm、120.4 ± 8.2 μm、165.3 ± 21.6 μm 和 270.2 ± 32.5 μm。水凝胶对溶胀率的影响，体外降解和机械性能进行了系统评估。TA 交联 PSA-Gel 水凝胶对革兰氏阳性（金黄色葡萄球菌）革兰氏阴性（大肠杆菌）菌株显示出很强的抗菌作用。此外，PSA-Gel-TA 水凝胶还对 L929 成纤维细胞系显示出良好的细胞毒性。最后，在体内研究了 PSA-Gel-TA 水凝胶的治疗和伤口愈合潜力使用大鼠切除伤口模型。结果表明，与天然 PSA-Gel 水凝胶和未处理对照组相比，PSA-Gel-TA 水凝胶对伤口闭合有更大和显着的影响，伤口愈合率在第 21 天分别提高了 94%、73% 和 65%。研究结果表明，PSA-Gel-TA 水凝胶是用于治疗伤口愈合的有前途的敷料材料。