Inertial imaging with nanomechanical systems.
Inertial imaging with nanomechanical systems.
复制标题
使用纳米力学系统进行惯性成像。
DOI：
10.1038/nnano.2015.32
复制
发表时间：
2015-04
影响因子：
38.3
通讯作者：
Roukes ML
中科院分区：
文献类型：
--
作者：
Hanay MS;Kelber SI;O'Connell CD;Mulvaney P;Sader JE;Roukes ML
在过去的十年中，纳米机电系统的质量传感技术有了长足的进步。有了纳米机电系统传感器，现在就有可能对气体分析物进行超灵敏的检测，实现原子尺度的质量分辨率，并对单个蛋白质进行质谱分析。在这里，我们展示了当单个分析物吸附到纳米机械谐振器上时，它在分子尺度上的质量空间分布可以实时成像。每个单分子吸附事件都会对器件的所有模式频率产生离散的、与时间相关的扰动。我们表明，通过连续监测多个振动模式，可以推导出单个分析物在吸附时的质量分布的空间矩。我们用多模频移的实验测量和数值模拟验证了这种方法用于惯性成像，分析了惯性质量、吸附位置以及单个分析物的大小和形状。与传统成像不同，通过纳米机械惯性成像可以检测到的最小分析物尺寸不受波长相关衍射现象的限制。相反，频率波动过程决定了最终可达到的分辨率。先进的纳米机电设备似乎能够分辨分子尺度的分析物。
Mass sensing with nanoelectromechanical systems has advanced significantly during the last decade. With nanoelectromechanical systems sensors it is now possible to carry out ultrasensitive detection of gaseous analytes, to achieve atomic-scale mass resolution and to perform mass spectrometry on single proteins. Here, we demonstrate that the spatial distribution of mass within an individual analyte can be imaged—in real time and at the molecular scale—when it adsorbs onto a nanomechanical resonator. Each single-molecule adsorption event induces discrete, time-correlated perturbations to all modal frequencies of the device. We show that by continuously monitoring a multiplicity of vibrational modes, the spatial moments of mass distribution can be deduced for individual analytes, one-by-one, as they adsorb. We validate this method for inertial imaging, using both experimental measurements of multimode frequency shifts and numerical simulations, to analyse the inertial mass, position of adsorption and the size and shape of individual analytes. Unlike conventional imaging, the minimum analyte size detectable through nanomechanical inertial imaging is not limited by wavelength-dependent diffraction phenomena. Instead, frequency fluctuation processes determine the ultimate attainable resolution. Advanced nanoelectromechanical devices appear capable of resolving molecular-scale analytes.