Zucker R M, Daniel K M, Massaro E J, Karafas S J, Degn L L, Boyes W K
U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Toxicology Assessment Division (MD-67), Research Triangle Park, NC 27711.
Cytometry A. 2013 Oct;83(10):962-72. doi: 10.1002/cyto.a.22342. Epub 2013 Aug 13.
The cellular uptake of different sized silver nanoparticles (AgNP) (10, 50, and 75 nm) coated with polyvinylpyrrolidone (PVP) or citrate on a human derived retinal pigment epithelial cell line (ARPE-19) was detected by flow cytometry following 24-h incubation of the cells with AgNP. A dose dependent increase of side scatter and far red fluorescence was observed with both PVP and citrate-coated 50 nm or 75 nm silver particles. Using five different flow cytometers, a far red fluorescence signal in the 700-800 nm range increased as much as 100 times background as a ratio comparing the intensity measurements of treated sample and controls. The citrate-coated silver nanoparticles (AgNP) revealed slightly more side scatter and far red fluorescence than did the PVP coated silver nanoparticles. This increased far red fluorescence signal was observed with 50 and 75 nm particles, but not with 10 nm particles. Morphological evaluation by dark field microscopy showed silver particles (50 and 75 nm) clumped and concentrated around the nucleus. One possible hypothesis to explain the emission of far red fluorescence from cells incubated with silver nanoparticles is that the silver nanoparticles inside cells agglomerate into small nano clusters that form surface plasmon resonance which interacts with laser light to emit a strong far red fluorescence signal. The results demonstrate that two different parameters (side scatter and far red fluorescence) on standard flow cytometers can be used to detect and observe metallic nanoparticles inside cells. The strength of the far red fluorescence suggests that it may be particularly useful for applications that require high sensitivity. © Published 2013 Wiley-Periodicals, Inc.
在人源视网膜色素上皮细胞系（ARPE - 19）中，用聚乙烯吡咯烷酮（PVP）或柠檬酸盐包被的不同尺寸（10、50和75纳米）的银纳米颗粒（AgNP）与细胞孵育24小时后，通过流式细胞术检测其细胞摄取情况。观察到PVP和柠檬酸盐包被的50纳米或75纳米银颗粒的侧向散射和远红荧光呈剂量依赖性增加。使用五种不同的流式细胞仪，在700 - 800纳米范围内的远红荧光信号，与处理样品和对照的强度测量值相比，背景增加了多达100倍。柠檬酸盐包被的银纳米颗粒（AgNP）显示出比PVP包被的银纳米颗粒略多的侧向散射和远红荧光。在50和75纳米颗粒中观察到这种增加的远红荧光信号，但在10纳米颗粒中未观察到。暗场显微镜的形态学评估显示银颗粒（50和75纳米）聚集并集中在细胞核周围。一个可能的假说来解释与银纳米颗粒孵育的细胞发出远红荧光的现象是，细胞内的银纳米颗粒聚集成小的纳米团簇，形成表面等离子体共振，与激光相互作用以发出强烈的远红荧光信号。结果表明，标准流式细胞仪上的两个不同参数（侧向散射和远红荧光）可用于检测和观察细胞内的金属纳米颗粒。远红荧光的强度表明它可能对需要高灵敏度的应用特别有用。© 2013年由Wiley - Periodicals, Inc.出版
