|AVS 54th International Symposium|
|In-situ Electron Microscopy Topical Conference||Monday Sessions|
|Session:||Dynamics of Nanostructures|
|Presenter:||N. de Jonge, Oak Ridge National Laboratory|
|Authors:||N. de Jonge, Oak Ridge National Laboratory
D.B. Peckys, University of Tennessee, Knoxville
G.M. Veith, Oak Ridge National Laboratory
S. Mick, Protochips Inc.
D.W. Piston, Vanderbilt University
S.J. Pennycook, Oak Ridge National Laboratory
D.C. Joy, University of Tennessee, Knoxville
|Correspondent:||Click to Email|
One of the main challenges of our time is the in-situ study of the molecular machinery of life in order to gain a fundamental understanding of how cells function at a molecular level. This challenge requires ways of imaging live cells. Recently, time-resolved confocal laser microscopy has been used to image protein function in living cells,1 but this method’s spatial resolution is on the order of the wavelength of light. Several new super-resolution techniques provide a high spatial resolution, but not temporal resolution.2 We have begun applying electron microscopy (EM) to image cells in a liquid environment at atmospheric pressures. EM has sub-nanometer resolution and typically exhibits fast image acquisition. Others developed liquid enclosures for high-resolution imaging with transmission electron microscopy (TEM).3 But, TEM imaging is sensitivite to materials with low atomic numbers, resulting in a strong background signal from the liquid and a low resolution for relevant volumes of liquid needed to image whole cells. Here, we present results from our new liquid scanning transmission electron microscopy (STEM) technique. STEM is insensitive to low z materials facilitating imaging through thicker samples. The liquid and the sample are enclosed between two ultra-thin windows of silicon nitride that are essentially electron transparent. Nanometer resolution and dynamic motion of gold nanoparticles enclosed in an aqueous environment will be reported. In addition we will present liquid STEM data from the high-resolution imaging of Ecoli bacteria labeled with quantum dots. Liquid STEM presents a new alternative to optical methods for time-resolved studies of intact Eukaryotic cells and bacteria. We are grateful to T. McKnight, R. Dona, G. Kremers, T.L. Harvey, C. Chisholm and P. Herrell. Research sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC for the U. S. Department of Energy under Contract No. DE-AC05-00OR22725.
1 J. Lippincott-Schwartz, E. Snapp, A. Kenworthy, Nature Reviews 2, 444 (2001).
2 V. Westphal, S. W. Hell, Phys. Rev. Lett. 94, 143903 (2005).
3 M. J. Williamson, R. M. Tromp, P. M. Vereecken, R. Hull, F. M. Ross, Nature Materials 2, 532 (2003).