MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
Phys Rev Lett. 2012 Sep 14;109(11):118302. doi: 10.1103/PhysRevLett.109.118302. Epub 2012 Sep 10.
We introduce all-electrical cross-correlation spectroscopy of molecular number fluctuations in nanofluidic channels. Our approach is based on a pair of nanogap electrochemical transducers located downstream from each other in the channel. When liquid is driven through this device, mesoscopic fluctuations in the local density of molecules are transported along the channel. We perform a time-of-flight measurement of these fluctuations by cross-correlating current-time traces obtained at the two detectors. Thereby we are able to detect ultralow liquid flow rates below 10 pL/min. This method constitutes the electrical equivalent of fluorescence cross-correlation spectroscopy.
我们介绍了在纳米流道中分子数涨落的全电式互相关光谱学。我们的方法基于一对纳米间隙电化学换能器，它们彼此位于通道下游。当液体通过这个装置时，分子局部密度的介观涨落沿着通道被传输。我们通过交叉相关在两个探测器上获得的电流时间迹线来测量这些涨落的飞行时间。由此，我们能够检测到低于 10 皮升/分钟的超低液体流速。这种方法构成了荧光互相关光谱学的电学等价物。
