Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL, 61801, USA.
Small. 2014 Apr 24;10(8):1642-51. doi: 10.1002/smll.201302835. Epub 2013 Dec 9.
The aggregation of gold nanoparticles (Au NPs) in cell media is a common phenomenon that can influence NP-cell interactions. Here, we control Au NP aggregation in cell media and study the impact of Au NP aggregation on human dermal fibroblast (HDF) cells. By first adding Au NPs to fetal bovine serum (FBS) and then subsequently to a buffer, aggregation can be avoided. Aggregation of Au NPs also can be avoided by coating Au NPs with other biomolecules such as lipids. The aggregation state of the Au NPs influences cellular toxicity and Au NP uptake: non-aggregated cationic Au NPs are four-fold less toxic to HDF cells than aggregated cationic Au NPs, and the uptake of non-aggregated anionic citrate Au NPs is three orders of magnitude less than that of aggregated citrate Au NPs. Upon uptake of Au NPs, cellular F-actin fiber formation is disrupted and actin dots are predominant. When lipid-coated Au NPs are doped with a fluorescent lipid (F-lipid) and incubated with HDF cells, the fluorescence from the F-lipid was found throughout the cell, showing that lipids can dissociate from the Au NP surface upon entering the cell.
金纳米粒子（Au NPs）在细胞培养基中的聚集是一种常见现象，会影响 NP-细胞相互作用。在这里，我们控制细胞培养基中 Au NPs 的聚集，并研究 Au NP 聚集对人真皮成纤维细胞（HDF）的影响。首先将 Au NPs 添加到胎牛血清（FBS）中，然后再添加到缓冲液中，可以避免 Au NPs 的聚集。通过用其他生物分子（如脂质）包覆 Au NPs 也可以避免 Au NPs 的聚集。Au NPs 的聚集状态会影响细胞毒性和 Au NP 的摄取：与聚集的阳离子 Au NPs 相比，非聚集的阳离子 Au NPs 对 HDF 细胞的毒性低四倍，而非聚集的阴离子柠檬酸盐 Au NPs 的摄取量比聚集的柠檬酸 Au NPs 低三个数量级。摄取 Au NPs 后，细胞中的 F-肌动蛋白纤维形成被破坏，肌动蛋白斑点占主导地位。当脂质包覆的 Au NPs 掺杂荧光脂质（F-脂质）并与 HDF 细胞孵育时，发现 F-脂质的荧光遍布整个细胞，表明脂质在进入细胞时可以从 Au NP 表面解离。
