Cerbino Roberto, Piotti Davide, Buscaglia Marco, Giavazzi Fabio
Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, via F.lli Cervi 93, 20090 Segrate, Italy.
J Phys Condens Matter. 2018 Jan 17;30(2):025901. doi: 10.1088/1361-648X/aa9bc5.
Micro- and nanoscale objects with anisotropic shape are key components of a variety of biological systems and inert complex materials, and represent fundamental building blocks of novel self-assembly strategies. The time scale of their thermal motion is set by their translational and rotational diffusion coefficients, whose measurement may become difficult for relatively large particles with small optical contrast. Here we show that dark field differential dynamic microscopy is the ideal tool for probing the roto-translational Brownian motion of anisotropic shaped particles. We demonstrate our approach by successful application to aqueous dispersions of non-motile bacteria and of colloidal aggregates of spherical particles.
具有各向异性形状的微米级和纳米级物体是各种生物系统和惰性复合材料的关键组成部分，也是新型自组装策略的基本构建单元。它们热运动的时间尺度由其平动和转动扩散系数决定，对于光学对比度较小的相对较大颗粒，测量这些系数可能会变得困难。在此，我们表明暗场差分动态显微镜是探测各向异性形状颗粒旋转平移布朗运动的理想工具。我们通过成功应用于非运动细菌的水分散体和球形颗粒的胶体聚集体来证明我们的方法。
