Department of Chemical Engineering , University of Washington , Seattle , Washington 98195 , United States.
Carnegie Mellon University , Pittsburgh , Pennsylvania 15213 , United States.
Langmuir. 2019 Feb 5;35(5):1984-1988. doi: 10.1021/acs.langmuir.8b03078. Epub 2018 Oct 9.
The effect of surface coatings on the performance of antifouling activity under flow can be influenced by the flow/coating interactions. This study evaluates the effect of surface coatings on antifouling activity under different flows for the analyses of coating stability. This was done by exposing DOPA-PCB-300/dopamine coated polydimethylsiloxane (PDMS) to physiological shear stresses using a recirculation system which consisted of dual chamber acrylic flow cells, tygon tubing, flow probe and meter, and perfusion pumps. The effect of shear stress induced by phosphate buffered saline flow on coating stability was characterized with differences in fibrinogen adsorption between control (coated PDMS not loaded with shear stress) and coated samples loaded with various shear stresses. Fibrinogen adsorption data showed that relative adsorption on coated PDMS that were not exposed to shear (5.73% ± 1.97%) was significantly lower than uncoated PDMS (100%, p < 0.001). Furthermore, this fouling level, although lower, was not significantly different from coated PDMS membranes that were exposed to 1 dyn/cm (9.55% ± 0.09%, p = 0.23), 6 dyn/cm (15.92% ± 10.88%, p = 0.14), and 10 dyn/cm (21.62% ± 13.68%, p = 0.08). Our results show that DOPA-PCB-300/dopamine coatings are stable, with minimal erosion, under shear stresses tested. The techniques from this fundamental study may be used to determine the limits of stability of coatings in long-term experiments.
表面涂层对流动条件下防污性能的影响可能受到流固相互作用的影响。本研究通过使用由双室亚克力流动池、特氟龙管、流动探针和流量计以及灌注泵组成的再循环系统，评估了不同流动条件下表面涂层对防污活性的影响，以分析涂层稳定性。该系统向多巴胺包裹的聚二甲基硅氧烷（PDMS）施加生理剪切应力，以模拟流动条件。通过比较控制组（未加载剪切力的涂层 PDMS）和加载不同剪切力的涂层样品之间纤维蛋白原吸附的差异，来表征由磷酸盐缓冲盐水流动引起的剪切力对涂层稳定性的影响。纤维蛋白原吸附数据表明，未暴露于剪切力的涂层 PDMS 的相对吸附率（5.73%±1.97%）明显低于未涂层 PDMS（100%，p<0.001）。此外，尽管这种污染水平较低，但与暴露于 1 dyn/cm（9.55%±0.09%，p=0.23）、6 dyn/cm（15.92%±10.88%，p=0.14）和 10 dyn/cm（21.62%±13.68%，p=0.08）的涂层 PDMS 膜相比，并无显著差异。我们的结果表明，DOPA-PCB-300/多巴胺涂层在测试的剪切应力下稳定，几乎没有侵蚀。这项基础研究中的技术可用于确定长期实验中涂层稳定性的极限。
