Xu Xin, Melcher John, Basak Sudipta, Reifenberger Ron, Raman Arvind
School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, USA.
Phys Rev Lett. 2009 Feb 13;102(6):060801. doi: 10.1103/PhysRevLett.102.060801.
Atomic Force microscope (AFM) cantilevers commonly used for imaging soft biological samples in liquids experience a momentary excitation of the higher eigenmodes at each tap. This transient response is very sensitive to the local sample elasticity under gentle imaging conditions because the higher eigenmode time period is comparable to the tip-sample contact time. By mapping the momentary excitation response, we demonstrate a new scanning probe spectroscopy capable of resolving with high sensitivity the variations in the elasticity of soft biological materials in liquids.
常用于在液体中对柔软生物样本进行成像的原子力显微镜（AFM）悬臂在每次轻敲时都会经历较高本征模式的瞬间激发。在温和成像条件下，这种瞬态响应对局部样本弹性非常敏感，因为较高本征模式的周期与针尖 - 样本接触时间相当。通过绘制瞬间激发响应图，我们展示了一种新的扫描探针光谱技术，它能够以高灵敏度分辨液体中柔软生物材料弹性的变化。
