Apr. 29, 2013

Patchwork Membrane in Budding Yeast

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. 08, 2013

Scanned LSFM with Confocal Detection

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].
moreMar. 25, 2013

Nano-FTIR - The Chemical Nanoscope

We show identification of chemical compounds and chemical maps at 20 nm resolution, enabled by a novel combination of infrared spectroscopy and near-field microscopy. Nano-FTIR returns the surface topography and simultaneously the local mid-infrared spectrum of the tiny volume (20 nm3) just below the probing tip thus allowing correlative topography/hyperspectral infrared images. In the case of molecular substances, comparison with common infrared databases enables local chemical recognition.
moreMar. 18, 2013

Light Sheet Ultramicroscopy

We developed a new ultramicroscopy design equipped with modified optics to achieve 3D-vizualizations of specimens with μm-resolution. The optical unit consists of elements with complex surface structures to create an ultra-thin light sheet. Diffraction and other unwanted optical effects are minimized, while the laser energy is used more efficiently. This enables us to obtain marked enhancements in resolving fine details of specimens (e.g. fruit-flies, entire mouse brains, and mouse hippocampi).
moreJan. 17, 2013

Single Molecule View on Polymerization

Single molecule fluorescence spectroscopy and microscopy techniques enable the analysis of diffusional processes for different polymerization systems at different conversions. The advantage of our techniques lies in the direct visualization of material heterogeneities evolving during the polymerization process by observing the diffusion of single molecules. Connecting single molecule behavior to polymerization kinetics and the structures and properties of the synthesized polymers is one of our main goals. moreOct. 29, 2012

Sparsity-Mediated Microscopy

We present the experimental reconstruction of sub-wavelength features from the far-field of sparse optical objects. We show that it is sufficient to know that the object is sparse, and only that, and recover 100 nm features with the resolution of 30 nm, for an illuminating wavelength of l = 532 nm. Our technique works in real-time, requires no scanning, and can be implemented in all existing microscopes - ­optical and non-optical.
moreSep. 20, 2012

Single Molecule Light Sheet Microscopy

All genetic information is stored on DNA safely concealed in the cell nucleus. Here it is copied to messenger RNA molecules, which export the genetic information across the nuclear envelope into the cytoplasm, where it is translated into proteins. Light sheet fluorescence microscopy and minimally invasive labeling strategies make it now possible to observe the dynamics of this process at the single molecule level deep within living tissue. moreSep. 13, 2012

Single Molecule Pointillism

Single molecule super-resolution imaging enables microscopists to go beyond the resolution limit set by optical diffraction, and to image structures much smaller than the wavelength of the probing light. Using variants of traditional microscopes, it reveals the previously unseeable, with the potential to revolutionize our understanding of the nanoscale structure of biological samples. more