Integrated Nanosystems Research Facility, Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA 92697, United States.
Department of Biomedical Engineering, University of California, Irvine, Irvine, CA 92697, United States.
Mitochondrion. 2017 Nov;37:8-16. doi: 10.1016/j.mito.2017.06.003. Epub 2017 Jun 24.
We report label-free detection of single mitochondria with high sensitivity using nanoelectrodes. Measurements of the conductance of carbon nanotube transistors show discrete changes of conductance as individual mitochondria flow over the nanoelectrodes in a microfluidic channel. Altering the bioenergetic state of the mitochondria by adding metabolites to the flow buffer induces changes in the mitochondrial membrane potential detected by the nanoelectrodes. During the time when mitochondria are transiently passing over the nanoelectrodes, this (nano) technology is sensitive to fluctuations of the mitochondrial membrane potential with a resolution of 10mV with temporal resolution of order milliseconds. Fluorescence based assays (in ideal, photon shot noise limited setups) are shown to be an order of magnitude less sensitive than this nano-electronic measurement technology. This opens a new window into the dynamics of an organelle critical to cellular function and fate.
我们报告了使用纳米电极对单个线粒体进行高灵敏度无标记检测的方法。碳纳米管晶体管的电导测量显示，当单个线粒体在微流道中的纳米电极上流动时，电导会发生离散变化。通过向流动缓冲液中添加代谢物来改变线粒体的生物能量状态，会导致纳米电极检测到的线粒体膜电位发生变化。当线粒体瞬时流过纳米电极时，这种（纳米）技术对线粒体膜电位的波动非常敏感，分辨率为 10mV，时间分辨率为毫秒级。荧光测定法（在理想的、光子散粒噪声限制的设置下）被证明比这种纳米电子测量技术的灵敏度低一个数量级。这为研究对细胞功能和命运至关重要的细胞器的动态提供了一个新窗口。
