CAS Key Lab of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Soft Matter. 2020 Jun 7;16(21):4912-4918. doi: 10.1039/d0sm00420k. Epub 2020 May 12.
Protein adsorption on polyelectrolyte (PE) surfaces has aroused intensive attraction, but there are still few investigations on tuning the protein adsorption at a solid surface by controllable layer structures and surface properties of PE adlayers. Furthermore, there is a lack of understanding regarding the correlation between molecular conformation and anticorrosion performance of composite materials. With this in mind, we synthesized a series of PEs and constructed 3,4-dihydroxy-l-phenylalanine (l-DOPA) adlayers on the PE surfaces, monitoring the whole adsorption process in situ. A highly charged cationic PE surface exhibits a low adhesion of DOPA molecules, leading to a loose structure, rough surface morphology, and strong solvation effects and, accordingly, this kind of multilayer provides a poor anticorrosion capacity. In comparison, amphiphilic and highly charged cationic PE surfaces are in favor of DOPA adsorption and the formation of compact and smooth multilayers due to cation-π and hydrophobic interactions between DOPA and PEs. Interestingly, one of the multilayers exhibits a remarkable enhancement of inhibition efficiency of about 460-fold compared with that of the bare substrate, which is much higher than that of other anticorrosion coatings reported previously. Our findings reveal the interaction mechanism between DOPA and PE surfaces to achieve the controllable adsorption of biomolecules, providing a promising way to optimize the layer structures to improve the anticorrosion capacity.
聚电解质（PE）表面的蛋白质吸附引起了人们的浓厚兴趣，但通过可控的层结构和聚电解质吸附层的表面性质来调节蛋白质在固体表面的吸附仍然很少得到研究。此外，对于复合材料的分子构象与耐腐蚀性能之间的相关性，人们的理解还很缺乏。有鉴于此，我们合成了一系列聚电解质，并在聚电解质表面构建了 3,4-二羟基-L-苯丙氨酸（L-DOPA）吸附层，原位监测整个吸附过程。带高电荷的阳离子聚电解质表面对 DOPA 分子的黏附性较低，导致结构松散、表面形貌粗糙、溶剂化作用较强，因此这种多层膜的耐腐蚀性能较差。相比之下，两性和带高电荷的阳离子聚电解质表面有利于 DOPA 的吸附和紧密、光滑的多层膜的形成，这是由于 DOPA 与聚电解质之间存在阳离子-π 和疏水相互作用。有趣的是，其中一个多层膜的抑制效率显著提高了约 460 倍，与裸基底相比，这比以前报道的其他防腐涂层高得多。我们的发现揭示了 DOPA 与聚电解质表面之间的相互作用机制，以实现对生物分子的可控吸附，为优化层结构以提高耐腐蚀性能提供了一种有前景的方法。
