Department of Chemistry , Iowa State University , Ames , Iowa 50011 , United States.
The Ames Laboratory , U.S. Department of Energy , Ames , Iowa 50011 , United States.
Anal Chem. 2018 Mar 6;90(5):3183-3188. doi: 10.1021/acs.analchem.7b04532. Epub 2018 Feb 15.
To establish a new method for tracking the interaction of nanoparticles with chemical cleaving agents, we exploited the optical effects caused by attaching 5-10 nm gold nanoparticles with molecular linkers to large mesoporous silica nanoparticles (MSN). At low levels of gold loading onto MSN, the optical spectra resemble colloidal suspensions of gold. As the gold is removed, by cleaving agents, the MSN revert to the optical spectra typical of bare silica. Time-lapse images of gold-capped MSN stationed in microchannels reveal that the rate of gold release is dependent on the concentration of the cleaving agent. The uncapping process was also monitored successfully for MSN endocytosed by A549 cancer cells, which produce the cleaving agent glutathione. These experiments demonstrate that the optical properties of MSN can be used to directly monitor cleaving kinetics, even in complex cellular settings.
为了建立一种新的方法来跟踪纳米粒子与化学裂解试剂的相互作用，我们利用了将 5-10nm 金纳米粒子与分子接头连接到较大的介孔硅纳米粒子（MSN）上所产生的光学效应。在 MSN 上的金负载量较低的情况下，光学光谱类似于胶体金悬浮液。随着金被裂解试剂去除，MSN 恢复为典型的裸露二氧化硅的光学光谱。驻留在微通道中的金覆盖 MSN 的延时图像显示，金的释放速率取决于裂解试剂的浓度。还成功地监测了被 A549 癌细胞内吞的 MSN 的去帽过程，癌细胞会产生裂解试剂谷胱甘肽。这些实验表明，MSN 的光学性质可用于直接监测裂解动力学，即使在复杂的细胞环境中也是如此。
