Nov. 01, 2008
Coherent anti-Stokes Raman scattering (CARS) microscopy is a branch of nonlinear microscopy that allows chemical imaging of targeted vibrational transitions in unstained samples. A resonantly enhanced blue-shifted CARS signal is generated from NIR or visible light, thus the method is more sensitive than normal Raman microscopy and offers better resolution than IR microscopy. CARS microscopes are mostly set up as confocal scanning microscopes, but wide-field approaches are possible as well.
Brief Introduction to CARS-microscopy moreNov. 01, 2008
Combining electron backscatter diffraction (EBSD), a scanning electron microscope (SEM) and a focused ion beam (FIB) together into a single instrument enables three dimensional (3D) characterization of microstructure in crystalline materials. Combining these techniques together has enormous potential in materials science.
Electron Backscatter Diffraction
Traditionally, microstructure refers to features that are visually evident in an optical or electron microscope. However, many critical aspects of microstructure are not visually evident. moreNov. 01, 2008
Ultrasonic AFM may improve fabrication technologies on the nanometer scale. In the presence of ultrasonic vibration, hard surfaces can be indented and scratched with the tip of a soft cantilever, due to its inertia. Ultrasound reduces or even eliminates friction, and hence modifies the tip-nanoparticle-surface interactions in AFM manipulation. The subsurface sensitivity of the technique makes feasible the purposed manipulation of subsurface nanoscale features by ultrasonic actuation.
Ultrasonic Atomic Force Microscopies moreNov. 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. more