Wilms Dimitri, Schröer Fabian, Paul Tanja J, Schmidt Stephan
Institute for Organic and Macromolecular Chemistry, Heinrich-Heine-University, Universitätsstr. 1, 40225 Düsseldorf, Germany.
Langmuir. 2020 Oct 27;36(42):12555-12562. doi: 10.1021/acs.langmuir.0c02040. Epub 2020 Oct 14.
Adhesion processes at the cellular scale are dominated by carbohydrate interactions, including the attachment and invasion of pathogens. Carbohydrate-presenting responsive polymers can bind pathogens and inhibit pathogen invasion by remote stimuli for the development of new antibiotic strategies. In this work, the adhesion forces of to monolayers composed of mannose-functionalized microgels with thermosensitive poly(-isopropylacrylamide) (PNIPAM) and poly(oligo(ethylene glycol)) (PEG) networks are quantified using single-cell force spectroscopy (SCFS). When exceeding the microgels' lower critical solution temperature (LCST), the adhesion increases up to 2.5-fold depending on the polymer backbone and the mannose density. For similar mannose densities, the softer PNIPAM microgels show a significantly stronger adhesion increase when crossing the LCST as compared to the stiffer PEG microgels. This is explained by a stronger shift in swelling, mannose density, and surface roughness of the softer gels when crossing the LCST. When using nonbinding galactose instead of mannose, or when inhibiting bacterial receptors, a certain level of adhesion remains, indicating that also polymer-fimbria entanglements contribute to adhesion. The presented quantitative analysis provides insights into carbohydrate-mediated bacterial adhesion and the relation to material properties and shows the prospects and limitations of interactive polymer materials to control the attachment of bacteria.
细胞尺度上的粘附过程主要由碳水化合物相互作用主导，包括病原体的附着和入侵。呈现碳水化合物的响应性聚合物可以结合病原体，并通过远程刺激抑制病原体入侵，以开发新的抗生素策略。在这项工作中，使用单细胞力谱（SCFS）对与由具有热敏性聚（N-异丙基丙烯酰胺）（PNIPAM）和聚（聚乙二醇）（PEG）网络的甘露糖功能化微凝胶组成的单层之间的粘附力进行了量化。当超过微凝胶的低临界溶液温度（LCST）时，粘附力会根据聚合物主链和甘露糖密度增加高达2.5倍。对于相似的甘露糖密度，与较硬的PEG微凝胶相比，较软的PNIPAM微凝胶在越过LCST时显示出明显更强的粘附力增加。这可以通过较软凝胶在越过LCST时溶胀、甘露糖密度和表面粗糙度的更强变化来解释。当使用非结合性半乳糖代替甘露糖，或抑制细菌受体时，仍会保留一定水平的粘附力，这表明聚合物-菌毛缠结也有助于粘附。所呈现的定量分析提供了对碳水化合物介导的细菌粘附以及与材料特性关系的见解，并展示了交互式聚合物材料在控制细菌附着方面的前景和局限性。
