Langmuir. 2018 Nov 20;34(46):14033-14045. doi: 10.1021/acs.langmuir.8b02572. Epub 2018 Nov 6.
Polydopamine (PDA)-coated nanoparticles are adhesive bionanomaterials widely utilized in intracellular applications, yet how their adhesiveness affects their colloidal stability and their interactions with serum proteins and mammalian cells remain unclear. In this work, we systematically investigate the combined effects of dopamine (DA) concentration and polymerization time (both reaction parameters spanning 2 orders of magnitude) on the morphological diversity of PDA-coated nanoparticles by coating PDA onto gold nanoparticle cores. Independent of the DA concentration, Au@PDA NPs remain largely aggregated upon several hours of limited polymerization; interestingly, extended polymerization for 2 days or longer yield randomly aggregated NPs, nearly monodisperse NPs, or worm-like NP chains in the ascending order of DA concentration. Upon exposure to serum proteins, the specific type of proteins adsorbed to the Au@PDA NPs strongly depends upon the DA concentration. As DA concentration increases, less albumin and more hemoglobin subunits adhere. Moreover, cellular uptake is a strong function of polymerization time. Serum-stabilized Au@PDA NPs prepared by limited polymerization enter Neuro-2a and HeLa cancer cells more abundantly than those prepared by extended polymerization. Our data underscore the importance of DA concentration and polymerization time for tuning the morphology and degree of intracellular delivery of PDA-coated nanostructures.
聚多巴胺 (PDA)-包覆的纳米粒子是一种广泛应用于细胞内应用的粘性仿生材料，但它们的粘性如何影响胶体稳定性以及与血清蛋白和哺乳动物细胞的相互作用尚不清楚。在这项工作中，我们通过在金纳米颗粒核上包覆 PDA，系统地研究了多巴胺 (DA) 浓度和聚合时间（这两个反应参数跨越两个数量级）对 PDA 包覆纳米粒子形态多样性的综合影响。独立于 DA 浓度，Au@PDA NPs 在数小时的有限聚合后仍主要聚集；有趣的是，延长聚合 2 天或更长时间会按 DA 浓度的升序产生随机聚集的 NPs、几乎单分散的 NPs 或蠕虫状 NP 链。暴露于血清蛋白后，吸附在 Au@PDA NPs 上的特定类型的蛋白质强烈依赖于 DA 浓度。随着 DA 浓度的增加，白蛋白的粘附量减少，血红蛋白亚基的粘附量增加。此外，细胞摄取是聚合时间的强函数。通过有限聚合制备的具有血清稳定性的 Au@PDA NPs 进入 Neuro-2a 和 HeLa 癌细胞的量比通过延长聚合制备的要多。我们的数据强调了 DA 浓度和聚合时间对于调节 PDA 包覆纳米结构的形态和细胞内递药程度的重要性。
