Juli 29, 2009
Physicists at New York University (NYU), US have developed a technique to record three-dimensional movies of microscopic systems, such as biological molecules, through holographic video. The technique, developed in the laboratory of NYU Physics Professor David Grier, is comprised of two components: making and recording the images of microscopic systems and then analyzing these images. To generate and record images, the researchers created a holographic microscope. It is based on a conventional light microscope, which uses a collimated laser beam instead of on an incandescent illuminator.
When an object is placed into path of the microscope’s beam, the object scatters some of the beam’s light into a complex diffraction pattern. The scattered light overlaps with the original beam to create an interference pattern reminiscent of overlapping ripples in a pool of water. The microscope then magnifies the resulting pattern of light and dark and records it with a conventional digital video recorder. Each snapshot in the resulting video stream is a hologram of the original object. Unlike a conventional photograph, each holographic snapshot stores information about the three-dimensional structure and composition of the object that created the scattered light field. The recorded holograms appear as a pattern of concentric light and dark rings.
For analyzing the images the researchers based their work on a quantitative theory, the Lorenz-Mie theory, which maintains that the way light is scattered can reveal the size and composition of the object that is scattering it.
The application of the technique ranges from research in fundamental statistical physics to analyzing the composition of fat droplets in milk.
In the microscope, a laser beam illuminates the sample. Light scattered by the sample creates an interference pattern which is magnified and recorded. Then measurements of the particle’s position, size, and refractive index are obtained.
Juni 29, 2009
Wyatt Technology Corporation will host its 20th Annual International Light Scattering Colloquium (ILSC) on October 19-20, 2009 at the Four Seasons Biltmore Resort in Santa Barbara, California, US. The event will welcome an array of high-profile speakers including Nobel Prize winner, Professor Robert Grubbs. In conjunction with the 20th annual ILSC, Wyatt Technology will also be hosting an Eclipse Field Flow Fractionation – MALS Focus Meeting on October 21, 2009. In this meeting the application focus will be proteins, biopolymers and liposome/virus particles.
April 6, 2009
Researchers at the University of Rochester have developed a novel optical technique that permits rapid analysis of single human immune cells using only light. Andrew Berger, associate professor of optics and his graduate student Zachary Smith integrated Raman and angular-scattering microscopy into a single system, which they call IRAM. This is the first time clear differences between two types of immune cells have been seen using a microscopy system that gathers chemical and structural information by combining two previously distinct optical techniques, according to Berger. „Conceptually it’s pretty straightforward – you shine a specified wavelength of light onto your sample and you get back a large number of peaks spread out like a rainbow,“ says Berger. „The peaks tell you how the molecules you’re studying vibrate and together the vibrations give you the chemical information.“ Until now scientists have not had a non-invasive way to see how human cells, like T cells or cancer cells, activate individually and evolve over time.
IRAM scattering data from a single granulocyte.
IRAM scattering data from a single lymphocyte. Clear differences are visible when compared to data from a granulocyte.
Januar 9, 2009
From Sunday April 5 to Wednesday April 8, 2009 the Focus on Microscopy (FOM) conference will take place in Krakow, Poland. It is the continuation of a yearly conference series presenting the latest innovations in optical microscopy and its application in biology, medicine and the material sciences. Key subjects are the theory and practice of 3D optical imaging, related 3D image processing, and reporting especially on developments in resolution and imaging modalities. The FOM conference also covers the rapidly advancing fluorescence labeling techniques for the confocal and multiphoton 3D imaging of live- biological-specimens. A technical exhibition will be a special feature of this year’s conference in Krakow.
Upcoming topics will cover:
– Confocal and multiphoton-excitation microscopy
– Novel illumination and detection strategies
– Fluorescence: new labels, fluorescent proteins, quantum dots, single molecule
– Time-resolved fluorescence: FRET, FRAP, FLIM, FCS
– Coherent non-linear microscopy: SHG, THG, SFG, CARS
– Raman, light scattering microscopy
– Multi-dimensional imaging
– Sub-wavelength resolution: near field microscopy, STED, PALM
– Laser manipulation, ablation and microdissection, photoactivation
– Optical tools in genomics, proteomics, phenomics, cytometry
– Magnetic resonance and X-ray microscopy
– Image processing and visualization
– Live cell and whole tissue imaging
The conference will take place at the Jagiellonian University Auditorium Maximum, ul. Krupnicza 35, in the center of Krakow.
Details for registration, abstract submission, deadlines, etc. will soon be available on:
Krakow, Poland (source: pixelio.de)