Speaker
Description
The Göttingen Instrument for Nano-Imaging with X-rays is the nanofocus-setup
at the coherence beamline P10 at PETRA III, DESY Hamburg. It features a 300 nm
Kirkpatrick-Baez mirror system as a prefocus for X-ray waveguide (WG) optics;
these WGs act as coherence filter and cleanup the X-ray beam from artefacts in
the illumination. In holography mode, sub-50 nm resolution of biological /
organic specimens becomes possible in three dimensions. In contrast, scanning
nano-SAXS in the focused beam provides local access to physical quantities,
e.g. orientations and sizes of collective scatterers such as sarcomeric
structures.
A super-resolving optical fluorescence microscope has been combined into the
X-ray micrscope. Using STimulated Emission Depletion (STED), the optical path
of the setup allows for imaging of labelled molecules at a resolution scale of
100 nm; combined with the X-ray holography, the labelled functional components
of biological cells (here: actin cytoskeleton in in cardiac tissue cells) can
be correlated to the electron density. Then, the nano-SAXS measurements
contribute spatially resolved scattering information.
We present a first correlative analysis combining STED and X-ray techniques on
nenoatal cariac tissue cells. We can infer that the actin filaments, which are
fluorescently labelled can be traced using STED, correlate to a significant
extent with the filaments as segmented in the holographic X-ray image. From
the nano-SAXS analysis, the filaments stand out by their anisotropic
scattering, and the preferential orientation is quantified.
