Jun. 18, 2013
Correlative light and electron microscopy (CLEM) combines the versatility of fluorescence microscopy (FLM) with the spatial resolution of transmission electron microscopy (TEM). For the analysis of tissues single resin or cryo-sections are incubated with fluorochrome- and gold-labeled probes. Areas of interest are selected at the FLM, and analyzed in the TEM at high resolution. This way, fluorescence is directly correlated to subcellular structures and/or corresponding immunogold signals. moreJun. 11, 2013
For excitable cells in which signaling events occur in milliseconds, a mathematical formalism for pixel-wise fitting generates virtually pixel noise-free image sequences from high-speed 2-dimensional confocal data. This approach provides novel insight into cardiac excitation-contraction coupling and its pathophysiology. Such an analytical approach can be extended into other biological systems to uncover otherwise inaccessible features of subcellular signal transduction in living cells.
moreJun. 07, 2013
The early growth stage and growth evolution to a unique gold (Au) honeycomb nano-network on Si(111)7×7 at room temperature have been studied by direct filled-state and empty-state imaging by scanning tunneling microscopy (STM). The gold honeycomb structure is made up of six triangular gold clusters around the corner hole interconnected to one another in the dimer rows of the Si(111)7×7 substrate. moreApr. 29, 2013
The plasma membrane (PM) is a selective barrier that separates cells from their environment and acts as signalling platform. Many PM proteins localize into characteristic domains but the molecular basis for their segregation is under debate. Using a combination of total internal reflection fluorescence microscopy and 2D deconvolution we visualized a large set of PM proteins in budding yeast. We found that the yeast PM self-organizes into numerous domains through weak protein-lipid interactions.
moreApr. 22, 2013
Scattering-type near-field optical microscopy (s-SNOM) is a powerful technique to image nano objects. It can be employed in a broad spectral range, namely the complete infrared region spanning from the terahertz range up to the visible range. In this article we describe a system which utilizes a free-electron laser as a spectrally narrow and widely tunable source of infrared radiation. This system was employed to study electrons confined in self-assembled InAs quantum dots. We spatially resolved single quantum dots upon resonant excitation of transitions between discrete energy levels of the confined electrons. moreApr. 16, 2013
We developed a new approach using cryo-correlative light and scanning transmission electron microscopy allowing analysis of targeted in situ intracellular ions and water measurements at the ultrastructural level within domains identified by examination of specific GFP-tagged proteins . We illustrate the potential of this approach by investigating changes in water and ion content in nuclear domains identified by GFP-tagged proteins in cells stressed by Actinomycin D treatment and controls. moreApr. 08, 2013
Light sheet fluorescence microscopy (LSFM) is a technique with a vivid development [1, 2]. In contrast to epi-illumination microscopy the sample is illuminated with a thin light sheet orthogonally to the detection path. Most often the sheet is formed by rapidly scanning a laser beam across the sample. This illumination yields intrinsic optical sectioning and reduction of photobleaching and phototoxicity since excitation is limited to fluorophores inside the observation plane. This is particularly beneficial for long term imaging in developmental biology and reduces image background [3-5]. moreApr. 02, 2013
The development of nanostructured lacquers and propellants needs to master the cellulose nitrate processing on the nanoscale. The challenge is the deposition of single cellulose nitrate molecules to image them with molecular resolution. We report on the effect of solvent, shaking duration and deposition techniques, from which the spray technique succeeded, for the first time to our knowledge, to image by Atomic Force Microscopy, individual molecular cellulose nitrate polymeric chains. more