Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, USA.
J Am Chem Soc. 2012 May 9;134(18):7628-31. doi: 10.1021/ja301880x. Epub 2012 Apr 30.
The synthesis and operation of a light-operated nanovalve that controls the pore openings of mesoporous silica nanoparticles containing gold nanoparticle cores is described. The nanoparticles, consisting of 20 nm gold cores inside ~150 nm mesoporous silica spheres, were synthesized using a unique one-pot method. The nanovalves consist of cucurbit[6]uril rings encircling stalks that are attached to the ~2 nm pore openings. Plasmonic heating of the gold core raises the local temperature and decreases the ring-stalk binding constant, thereby unblocking the pore and releasing the cargo molecules that were preloaded inside. Bulk heating of the suspended particles to 60 °C is required to release the cargo, but no bulk temperature change was observed in the plasmonic heating release experiment. High-intensity irradiation caused thermal damage to the silica particles, but low-intensity illumination caused a local temperature increase sufficient to operate the valves without damaging the nanoparticle containers. These light-stimulated, thermally activated, mechanized nanoparticles represent a new system with potential utility for on-command drug release.
描述了一种光操作的纳米阀的合成和操作，该纳米阀控制含有金纳米核的介孔硅纳米粒子的孔开口。这些纳米粒子由 20nm 金核和大约 150nm 的介孔硅球组成，使用独特的一锅法合成。纳米阀由葫芦[6]脲环环绕附着在大约 2nm 孔开口处的支链组成。金核的等离子体加热会提高局部温度并降低环支结合常数，从而打开孔并释放预先装载在内部的货物分子。需要将悬浮颗粒加热到 60°C 以释放货物，但在等离子体加热释放实验中未观察到整体温度变化。高强度辐照会对硅粒子造成热损伤，但低强度光照会导致局部温度升高，足以在不损坏纳米粒子容器的情况下操作阀门。这些光刺激、热激活、机械纳米粒子代表了一种新的系统，具有潜在的按需药物释放的应用价值。
