Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.
Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland; Department of Earth- and Environmental Sciences, Ludwig Maximilian University of Munich, Theresienstrasse 41, 80333 Munich, Germany.
J Colloid Interface Sci. 2022 Sep 15;622:419-430. doi: 10.1016/j.jcis.2022.04.084. Epub 2022 Apr 16.
Bacterial infections related to medical devices can cause severe problems, whose solution requires in-depth understanding of the interactions between bacteria and surfaces. This work investigates the influence of surface physicochemistry on bacterial attachment and detachment under flow through both empirical and simulation studies. We employed polydimethylsiloxane (PDMS) substrates having different degrees of crosslinking as the model material and the extended Derjaguin - Landau - Verwey - Overbeek model as the simulation method. Experimentally, the different PDMS materials led to similar numbers of attached bacteria, which can be rationalized by the identical energy barriers simulated between bacteria and the different materials. However, different numbers of residual bacteria after detachment were observed, which was suggested by simulation that the detachment process is determined by the interfacial physicochemistry rather than the mechanical property of a material. This finding is further supported by analyzing the bacteria detachment from PDMS substrates from which non-crosslinked polymer chains had been removed: similar numbers of residual bacteria were found on the extracted PDMS substrates. The knowledge gained in this work can facilitate the projection of bacterial colonization on a given surface.
与医疗器械相关的细菌感染可能会导致严重的问题，解决这些问题需要深入了解细菌与表面之间的相互作用。这项工作通过实验和模拟研究调查了表面物理化学性质对流动条件下细菌附着和脱落的影响。我们使用具有不同交联度的聚二甲基硅氧烷（PDMS）作为模型材料，并采用扩展的 Derjaguin-Landau-Verwey-Overbeek 模型作为模拟方法。实验结果表明，不同的 PDMS 材料导致附着细菌的数量相似，这可以通过细菌与不同材料之间模拟的相同能量势垒来合理化。然而，观察到脱落后残留细菌的数量不同，模拟表明脱落过程取决于界面物理化学性质，而不是材料的机械性能。通过分析从 PDMS 基质中去除非交联聚合物链后的细菌脱落，进一步支持了这一发现：在提取的 PDMS 基质上发现了相似数量的残留细菌。这项工作获得的知识可以促进对给定表面细菌定殖的预测。
