Physics

Dr. Roberto Cerbino
Universit�  degli Studi di Milano

Differential dynamic microscopy (DDM) is a technique that exploits optical microscopy to obtain local, multi-scale quantitative information about dynamic samples, in most cases without user intervention. It is proving extremely useful in understanding dynamics in liquid suspensions, soft materials, cells, and tissues. In DDM, image sequences are analyzed via a combination of image differences and spatial Fourier transforms to obtain information equivalent to that obtained by means of light scattering techniques. For many questions, DDM has advantages compared to scattering techniques, as well as to segmentation/tracking and correlation techniques like particle image velocimetry. The very straightforward DDM approach, originally demonstrated with bright field microscopy of aqueous colloids [1], has lately been used to probe a variety of other complex fluids and biological systems with many imaging methods, including dark-field, differential interference contrast, wide-field, light-sheet, and confocal microscopy [2]. The number of adopting groups is rapidly increasing and so are the applications. Here, we briefly recall the working principles of DDM, we highlight its advantages and limitations, we outline recent experimental breakthroughs, and we provide a perspective on future challenges and directions [3].

References
[1] R. Cerbino, V. Trappe, Phys. Rev. Lett. 16 2014, 083001
[3] R. Cerbino, P. Cicuta, J. Chem. Phys.