Center for Biomaterials, University of Connecticut Health Center, Farmington, Connecticut 06030-1715, USA.
Biointerphases. 2011 Jun;6(2):43-53. doi: 10.1116/1.3583535.
An ideal surface for implantable glucose sensors would be able to evade the events leading to chronic inflammation and fibrosis, thereby extending its utility in an in vivo environment. Nafion™, a perfluorinated ionomer, is the membrane material preferred for in situ glucose sensors. Unfortunately, the surface properties of Nafion™ promote random protein adsorption and eventual foreign body encapsulation, thus leading to loss of glucose signal over time. Details of the techniques to render Nafion™ nonprotein fouling are given in a previous article [T. I. Valdes et al., Biomaterials 29, 1356 (2008)]. Once random protein adsorption is prevented, a biologically active peptide can be covalently bonded to the treated Nafion™ to induce cellular adhesion. Cellular responses to these novel decorated Nafion™ surfaces are detailed here, including cell viability, cell spreading, and type I collagen synthesis. Normal human dermal fibroblasts (NHDFs) were cultured on control and modified Nafion™ surfaces. Findings indicate that Nafion™ modified with 10% 2-hydroxyethyl methacrylate and 90% tetraglyme created a nonfouling surface that was subsequently decorated with the YRGDS peptide. NHDFs were shown to have exhibited decreased type I collagen production in comparison to NHDF cells on unmodified Nafion™ surfaces. Here, the authors report evidence that proves that optimizing conditions to prevent protein adsorption and enhance cellular adhesion may eliminate fibrous encapsulation of an implant.
理想的植入式葡萄糖传感器表面应该能够避免导致慢性炎症和纤维化的事件，从而延长其在体内环境中的应用。全氟磺酸离子交换膜（Nafion™）是原位葡萄糖传感器中首选的膜材料。不幸的是，Nafion™的表面性质会促进随机蛋白质吸附，并最终导致异物包裹，从而导致葡萄糖信号随时间丢失。在之前的一篇文章中给出了使 Nafion™ 无蛋白污染的技术细节[T. I. Valdes 等人，生物材料 29, 1356 (2008)]。一旦阻止了随机蛋白质吸附，就可以将生物活性肽共价键合到处理过的 Nafion™上，以诱导细胞黏附。本文详细介绍了这些新型修饰的 Nafion™表面的细胞反应，包括细胞活力、细胞铺展和 I 型胶原合成。将正常人皮肤成纤维细胞（NHDF）在对照和修饰的 Nafion™表面上进行培养。研究结果表明，用 10% 2-羟乙基甲基丙烯酸酯和 90% 四甘醇修饰的 Nafion™形成了非污染表面，随后用 YRGDS 肽进行了修饰。与未修饰的 Nafion™表面上的 NHDF 细胞相比，NHDF 细胞表现出 I 型胶原蛋白产生减少。在这里，作者报告了证据证明，优化条件以防止蛋白质吸附并增强细胞黏附可能会消除植入物的纤维包裹。
