Tian Chenxu, Luo Feng, Li Jiehua, He Xueling
（ 610065） College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China.
Sichuan Da Xue Xue Bao Yi Xue Ban. 2024 Jul 20;55(4):853-860. doi: 10.12182/20240760202.
This study aims to develop a medical patch surface material featuring a microporous polyurethane (PU) membrane and to assess the material's properties and biological performance. The goal is to enhance the clinical applicability of pelvic floor repair patch materials.
PU films with a microporous surface were prepared using PU prepolymer foaming technology. The films were produced by optimizing the PU prepolymer isocyanate index ( value) and the relative humidity (RH) of the foaming environment. The surface morphology of the PU microporous films was observed by scanning electron microscopy, and the chemical properties of the PU microporous films, including hydrophilicity, were analyzed using infrared spectroscopy, Raman spectroscopy, and water contact angle measurements. evaluations included testing the effects of PU microporous film extracts on the proliferation of L929 mouse fibroblasts and observing the adhesion and morphology of these fibroblasts. Additionally, the effect of the PU microporous films on RAW264.7 mouse macrophages was studied. Immune response and tissue regeneration were assessed using Sprague Dawley (SD) rats.
The PU films exhibited a well-defined and uniform microporous structure when the value of PU prepolymer=1.5 and the foaming environment RH=70%. The chemical structure of the PU microporous films was not significantly altered compared to the PU films, with a significantly lower water contact angle ([55.7±1.5]° ) compared to PU films ([69.5±1.7]° ) and polypropylene (PP) ([ 104.3±2.5]°), indicating superior hydrophilicity. The extracts from PU microporous films demonstrated good biocompatibility, promoting the proliferation of L929 mouse fibroblasts. The surface morphology of the PU microporous films facilitated fibroblast adhesion and spreading. The films also inhibited the secretion of tumor necrosis factor-α (TNF-α) and interleukin (IL)-1β by RAW264.7 macrophages while enhancing IL-10 and IL-4 secretion. Compared to 24 hours, after 72 hours of culture, the expression levels of TNF-α and IL-1β were reduced in both the PU film and PU microporous film groups and were significantly lower than those in the PP film group (<0.05), with the most notable decreases observed in the PU microporous film group. IL-10 and IL-4 levels increased significantly in the PU microporous film group, surpassing those in the PP film group (<0.01), with the most pronounced increase in IL-4. The PU microporous film induced mild inflammation with no significant fibrous capsule formation . After 60 days of implantation, the film partially degraded, showing extensive collagen fiber growth and muscle formation in its central region.
The PU microporous film exhibits good hydrophilicity and biocompatibility. Its surface morphology enhances cell adhesion, regulates the function of RAW264.7 macrophages, and promotes tissue repair, offering new insights for the design of pelvic floor repair and reconstruction patch materials.
本研究旨在开发一种具有微孔聚氨酯（PU）膜的医用贴片表面材料，并评估该材料的性能和生物学性能。目标是提高盆底修复贴片材料的临床适用性。
采用PU预聚物发泡技术制备具有微孔表面的PU膜。通过优化PU预聚物异氰酸酯指数（值）和发泡环境的相对湿度（RH）来生产这些膜。用扫描电子显微镜观察PU微孔膜的表面形态，并用红外光谱、拉曼光谱和水接触角测量分析PU微孔膜的化学性质，包括亲水性。评估包括测试PU微孔膜提取物对L929小鼠成纤维细胞增殖的影响，并观察这些成纤维细胞的黏附及形态。此外，研究了PU微孔膜对RAW264.7小鼠巨噬细胞的影响。使用斯普拉格-道利（SD）大鼠评估免疫反应和组织再生情况。
当PU预聚物的值=1.5且发泡环境RH=70%时，PU膜呈现出明确且均匀的微孔结构。与PU膜相比，PU微孔膜的化学结构没有明显改变，其水接触角（[55.7±1.5]°）明显低于PU膜（[69.5±1.7]°）和聚丙烯（PP）（[104.3±2.5]°），表明具有优异的亲水性。PU微孔膜提取物显示出良好的生物相容性，促进L929小鼠成纤维细胞的增殖。PU微孔膜的表面形态有利于成纤维细胞的黏附和铺展。这些膜还抑制RAW264.7巨噬细胞分泌肿瘤坏死因子-α（TNF-α）和白细胞介素（IL）-1β，同时增强IL-10和IL-4的分泌。与24小时相比，培养72小时后，PU膜组和PU微孔膜组中TNF-α和IL-1β的表达水平均降低，且显著低于PP膜组（<0.05），PU微孔膜组下降最为明显。PU微孔膜组中IL-10和IL-4水平显著升高，超过PP膜组（<0.01），IL-4升高最为显著。PU微孔膜引起轻度炎症，无明显纤维囊形成。植入60天后，膜部分降解，在其中心区域显示出广泛的胶原纤维生长和肌肉形成。
PU微孔膜具有良好的亲水性和生物相容性。其表面形态增强细胞黏附，调节RAW264.7巨噬细胞的功能，并促进组织修复，为盆底修复和重建贴片材料的设计提供了新的见解。
