Seitz Uwe, Block Andreas, Schaefer Ann-Christina, Wienhold Uwe, Bohnacker Sabine, Siebert Klaus, Seewald Stefan, Thonke Frank, Wulff Holger, De Weerth Andreas, Soehendra Nib
Department of Interdisciplinary Endoscopy, University Medical Center Eppendorf, Hamburg, Gernany.
Gastroenterology. 2007 Jul;133(1):65-71. doi: 10.1053/j.gastro.2007.04.006.
BACKGROUND & AIMS: The major drawback of plastic stents for biliary drainage is the occlusion by sludge. Sludge is accrued because the stent surface allows for the adherence of proteins, glycoproteins, or bacteria and the bile flow is insufficient to clean the surface. In this study, experience from nanotechnology to achieve a clean surface by improved soil-release characteristics is used to optimize biliary stent surface. The aim of this study was to examine sludge accumulation in relation to surface characteristics designed by nanotechnology.
A variety of inorganic-organic sol-gel-coated stents were incubated in sterilized human bile and enzyme-active Escherichia coli for 35 days. Materials were Teflon (DuPont, Wilmington, DE) coated with hydrophobic Clearcoat (NTC, Tholey, Germany), Teflon with sol-gel coating synthesized of organic epoxides of 190 g/mol or 500 g/mol, and propylaminosilane without or with fluorsilanes for increased hydrophobicity. Scanning electron microscopy and semiquantitative analysis, blinded to the type of coating, were used to determine the amount of sludge accumulated on the surface.
Sludge deposition was reduced on the designed surfaces as compared with uncoated Teflon and Clearcoat. The performance of high molecular (500 g/mol) was superior to that of low molecular (190 g/mol) epoxide ligand. However, increasing hydrophobicity by adding fluoraminosilanes resulted in increased adherence of sludge. Less than a micrometer-thin sol-gel coating is inexpensive because very little coating material is required. This is the first published data comparing systematically modified surfaces of biliary stents using nanotechnology.
Optimized soil release by sol-gel nanocoating of plastic stents may prevent biliary plastic stents from clogging.
用于胆道引流的塑料支架的主要缺点是被胆泥堵塞。胆泥的形成是因为支架表面会吸附蛋白质、糖蛋白或细菌，且胆汁流动不足以清洁表面。在本研究中，利用纳米技术改善表面防污特性以实现清洁表面的经验被用于优化胆道支架表面。本研究的目的是研究与纳米技术设计的表面特性相关的胆泥积聚情况。
将各种无机 - 有机溶胶 - 凝胶涂层支架在灭菌的人胆汁和具有酶活性的大肠杆菌中孵育35天。材料包括涂有疏水性清漆（德国索利NTC公司）的聚四氟乙烯（美国杜邦公司，特拉华州威尔明顿）、涂有190 g/mol或500 g/mol有机环氧化物合成的溶胶 - 凝胶涂层的聚四氟乙烯，以及添加或不添加氟硅烷以增加疏水性的丙基氨基硅烷。采用扫描电子显微镜和半定量分析（对涂层类型不知情）来确定表面积聚的胆泥量。
与未涂层的聚四氟乙烯和清漆相比，设计表面上的胆泥沉积减少。高分子量（500 g/mol）环氧化物配体的性能优于低分子量（190 g/mol）的。然而，添加氟氨基硅烷增加疏水性会导致胆泥附着力增加。厚度小于一微米的溶胶 - 凝胶涂层成本低廉，因为所需涂层材料很少。这是首次发表的系统比较使用纳米技术对胆道支架表面进行改性的数据。
通过塑料支架的溶胶 - 凝胶纳米涂层优化防污性能可防止胆道塑料支架堵塞。
