Dec. 27, 2011

Time-Gated STED Microscopy

Stimulated emission depletion microscopy has been used to overcome the diffraction limit of confocal fluorescence microscopy. By exploiting information present in the arrival time of fluorescence photons through time-gating, the resolution of STED microscopes can be improved significantly. The resolution improvement of this technique - termed "T-STED" - becomes most evident in CW-STED where the STED beam is of long duration compared to the lifetime of the fluorophore.

Introduction
moreNov. 28, 2011

Core Facility Management

Managing an imaging core facility with numerous microscopes and many ever-changing users requires tools that track user contact and project data, allows easy communication between facility users and staff, and monitors the performance of the microscopes. Commercial tools are too general for these specific tasks, thus we developed a customized Core Facility Management tool-box that includes a user database, online user registration and contact forms, booking and trouble ticket system and a Wiki.
moreNov. 22, 2011

Optically Measuring Single Cell Mass

The ability to measure single cell growth is of fundamental importance to our understanding of biological systems. Despite several major efforts, studying this phenomenon has remained largely intangible due to the simple fact that cells are small and only double their mass during their lifetime. In order to draw conclusions on growth trends and gain insight on growth regulatory systems, the required sensitivity to mass is in the order of femtograms.

Introduction
moreNov. 07, 2011

Lensfree Optical Tomography

Light microscopy has traditionally relied on lenses to create microscopic images of small objects. Exploiting the recent advances in sensor technologies and digital processing algorithms, lensfree on-chip holographic microscopy takes a different approach to achieve high-resolution optical imaging without compromising the field-of-view. Along these lines, here we present a lensfree optical tomography approach for high-throughput on-chip 3D microscopy applications. moreNov. 02, 2011

Imaging Motile Malaria Parasites

Cell motility is an essential process for most uni- and multi-cellular forms of life. The study of evolutionary ancient and thus divergent cells can yield interesting insights into our very basic understanding of molecular processes conferring cellular motility. The Plasmodium sporozoite represents a unique cell that migrates in vitro in near perfect circles due to its crescent shape. This allows the combination of high throughput imaging with reverse genetics to dissect how these cells move. moreSep. 26, 2011

A New Twist to Quantum Dot Tracking - New Nanoparticle Changes Color Continuously

There are three issues, all of which are related to blinking, in quantum dot-based particle/molecule tracking. The recently reported "non-blinking quantum dots" address only one of the three issues. Here we report a new class of quantum dot-based composite nanoparticles that emit fluorescence with continuous intensity and alternating color, effectively addressing all three blinking-related issues, as well as providing greatly enhanced brightness compared with single quantum dots. moreSep. 12, 2011

Synthetic Biology - A New Way to Access Biological Phenomena

The history of cell and molecular biology displays an arms race between biological challenges and their technological solutions, regarding the detection and analysis of ever smaller structures and processes. For a long time, advancements in microscopy have kept pace with scientific motivations. But since fundamental physical laws cannot be simply overcome, appropriate instruments need to become more and more complex if modern biology does not simply want to stand still due to technical limitations. moreAug. 29, 2011

Measuring Nanodistances in Cells

Understanding how complex processes such as receptor signal transduction work in cells requires knowledge of the structure-function relationships underlying the composition of protein complexes. Characterization of the oligomerization state of complexes requires the measurement of distances around 10-15 nm, too long for fluorescence energy transfer (FRET), but too small for optical resolution. Here we discuss various approaches that are being taken to mea­sure these distances in cells.

Spatial Resolution Requirements for Cell Biology
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