University of Marburg tests nanometer resolution light microscopes
19 March 2011
The University of Marburg is expanding its cooperation with
Leica Microsystems to test a new generation of light microscopes with a
resolution at the nanometer scale.
The University's Institute of Cytobiology is currently one of four
institutes in the world testing a microscope with a resolution well
below the diffraction limit (nanoscope).
The new technology, for which Leica Microsystems has been granted an
exclusive licence, is being tested until September in the Imaging
Core Facility of the special Cell Biology Research Department in
“With this new optical nanoscopy called GSDIM (ground state
depletion microscopy followed by individual molecule return),
resolutions down to 25 nanometers can be achieved. This makes it
possible to image sub-cellular structures or protein complexes far
beyond the resolving powers of a light microscope,” says cell
biologist Prof Dr Ralf Jacob of Philipps University, Marburg.
GSDIM gives true-to-detail imaging of the spatial arrangement of
proteins and other biomolecules in cells and observing molecular
processes by giving resolutions beyond the diffraction limit. The
more insight science gains into these basic processes of life, the
better it can find the causes of previously incurable diseases and
develop suitable therapies.
One of the strengths of GSDIM is that it uses conventional
fluorescence markers to image proteins or other biomolecules within
the cells with sharpness down to a few nanometers. This includes
fluorophores which are routinely used in biomedicine.
With GSDIM, the fluorescent molecules in the specimen are almost
completely switched off using laser light. However, individual
molecules spontaneously return to the fluorescent state, while their
neighbours remain non-illuminating.
In this way, the signals of individual molecules can be acquired
sequentially using a highly sensitive camera system and their
spatial position in the specimen can be measured and stored. An
extremely high-resolution image can then be created from the
position of many thousands of molecules.
This enables cell components that are situated very close to one
another and cannot be resolved using conventional widefield
fluorescence microscopy to be spatially separated and sharply
reproduced in an image.
“With this new widefield microscope system we are extending our
super-resolution portfolio and allow even more scientists to benefit
from our innovative technology and advance their research,” said
Anja Schué from Leica Microsystems.