Molecular Light Switches for Higher Resolution

Mai 29, 2009

The “Superresolution” research network, founded by the German Ministry of Education and Sciences, demonstrated a new widefield microscopy technology with resolutions better than 20 nanometers. The method is based on special dyes, which’s fluorescence can be optically and reversibly switched on and off in aqueous solutions. The dyes are bond to cellular structures by using a functional group. By switching the dyes on and off, the fluorescence emission is separated in time until only those dye molecules fluoresce that have enough distance to allow their localization as single molecules. After several thousand switching cycles, a total image is constructed (dSTORM – direct stochastic optical reconstruction microscopy). Involved in the project were the work groups of Prof. Dr. M. Sauer and Prof. Dr. J. Mattay (University of Bielefeld, Germany ), Prof. Dr. K.-H. Drexhage (University of Siegen, Germany), Prof. Dr. J. Enderlein (University of Goettingen, Germany), and Prof. Dr. S. Hell (Max Planck Institute of Biophysical Chemistry, Goettingen, Germany).

Cytoskeleton of a fixed cell. Left: Fluorescence image at standard conditions. Right: dSTORM image using molecular switches.

Cytoskeleton of a fixed cell. Left: Fluorescence image at standard conditions. Right: dSTORM image using molecular switches.


Light Microscopy Meets Structural Biology

April 21, 2009

A symposium with a focus on light microscopy and its application in structural biology, organized by the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany will take place form June 22-23, 2009. The symposium aims to bring together structural biologists, cell biologists and light microscopy specialists to explore opportunities and requirements for structural biologists in using different light microscopy techniques and to foster interactions at the interface between structural biology and cell biology.

Planned sessions include:
– Imaging protein-protein interactions
– Protein dynamics
– Correlative light- electron microscopy
– Super-resolution techniques

Deadline for registration is May 3, 2009.

Heidelberg, Germany (source:

Heidelberg, Germany (source:

3D Single Molecule Imaging

März 20, 2009

A team of researchers led by professor Rafael Piestun of the department of electrical and computer engineering at the University of Colorado and William E. Moerner, professor of chemistry at Stanford University, have demonstrated for the first time a method for three-dimensional optical imaging of objects smaller than 20 nanometers over a wide spatial range. Optical imaging at these scales is of great interest in biomedical sciences and nanotechnology. The new findings, which provide a powerful tool for the super resolution of single molecules, have implications for characterizing defects in materials, the characterization of nanostructures, and the three-dimensional, biophysical and biomedical imaging of tagged molecules inside and outside of cells.

3D single molecule imging

3D single molecule imaging