Nov. 01, 2008
Focused Ion Beam instruments (FIB) are used for the preparation of electron microscopy specimens and for the fabrication of nano and micro components. Using polycrystalline Cu as an example, the influence of the crystallographic orientation, as obtained by EBSD, on the milling result is demonstrated. Different milling rates are due to the channeling effect. With some orientations a topography with characteristic features, like ripples, is generated, which were quantified using AFM images.
moreNov. 01, 2008
Packaging drugs and genes into nanoparticles enables drug or gene biodistribution to be favourably altered, with an ultimate therapeutic benefit [1-3]. To acquire such control on the in vivo fate of drugs and genes requires that such particles be precision engineered and electron microscopy is one of the techniques used to visualise and confirm the results of such engineering.
Methods moreNov. 01, 2008
A new protocol for functionalizing sample holders has been developed for 360° TEM/STEM observation of nanoparticles and nanostructures. The three step process includes FIB milling to customize sample stub geometry, thin film deposition for substrate selection and subsequent chemical functionalization for nanoparticle adhesion. This protocol was used to determine the morphology and local material properties of individual Au/SiO2 core-shell nanoparticles used in a DNA detection assay.
Nanoscience Imaging & Spectroscopy moreNov. 01, 2008
Fluorescence Recovery after Photobleaching (FRAP) is a versatile technique to study dynamic phenomena. Performing FRAP on a confocal laser scanning microscope documents the recovery process with high spatial resolution. This enables a consistent determination of the diffusion coefficient and the dimensionality of diffusion in calibration-free manner. Moreover, experiments representing multi-component diffusion can be analyzed as well, thus yielding the distribution of diffusion coefficients
Introduction moreSep. 01, 2008
Fundamental Knowledge - Part 4: Digitial Imaging Cameras: Deciphering Specifications. In the first instalments of this article series we looked at the theory behind microscopy: how a small facet of a sample can be magnified and focused efficiently and effectively at the focal plan of the user's eyes or the imaging device. In this article, we look at the surprisingly complex world of digital microscopy cameras and how to find the best one for each research task. moreSep. 01, 2008
Optical Simulation Improves Biomedical Devices: Virtual Prototyping Software. Photonic devices play an indispensable role in today's bio-medical industry. For the last quarter century, timely design and delivery to market of these new technologies has been possible only with the aid of sophisticated software tools and experienced optical engineers. Modern optical engineering tools such as FRED help accelerate the pace of innovation in the biomedical community by enabling its members to participate more fully in the process. moreSep. 01, 2008
Intracytoplasmic Morphologically Selected Sperm Injection: The success of in vitro fertilisation techniques such as intracytoplasmic sperm injection (ICSI) depends critically on selection of the most healthy sperm for injection into the oocyte. Intracytoplasmic morphologically selected sperm injection (IMSI) is a high magnification light microscopy imaging method that is being used increasingly to select sperm for ICSI. IMSI has been shown to increase pregnancy rates and reduce abortion rates compared to routine ICSI-IVF. moreSep. 01, 2008
Aberration Corrected STEM and EELS: Atomic Scale Chemical Mapping - The ultimate aim of an analytical technique applied to a solid material could be stated as the identification and mapping of the constituent atoms and their bonding in three dimensions. Hitherto, this was almost always achieved by diffraction methods averaging over many identical structures and, where it can be used, this remains the most powerful approach. more