To Study Biological Molecules and Structures

August 31, 2009

Researchers in the United States and Spain have discovered that a tool widely used in nanoscale imaging works differently in watery environments, a step toward better using the instrument to study biological molecules and structures.

The researchers demonstrated their new understanding of how the instrument – the atomic force microscope – works in water to show detailed properties of a bacterial membrane and a virus called Phi29, said Arvind Raman, a Purdue professor of mechanical engineering. An atomic force microscope uses a tiny vibrating probe to yield information about materials and surfaces on the scale of nanometers, or billionths of a meter. Because the instrument enables scientists to „see“ objects far smaller than possible using light microscopes, it could be ideal for studying molecules, cell membranes and other biological structures. The best way to study such structures is in their wet, natural environments. However, the researchers have now discovered that in some respects the vibrating probe’s tip behaves the opposite in water as it does in air, said Purdue mechanical engineering doctoral student John Melcher. The probe is caused to oscillate by a vibrating source at its base. However, the tip of the probe oscillates slightly out of synch with the oscillations at the base. This difference in oscillation is referred to as a „phase contrast,“ and the tip is said to be out of phase with the base.

Although these differences in phase contrast reveal information about the composition of the material being studied, data can’t be properly interpreted unless researchers understand precisely how the phase changes in water as well as in air, Raman said.

If the instrument is operating in air, the tip’s phase lags slightly when interacting with a viscous material and advances slightly when scanning over a hard surface. Now researchers have learned the tip operates in the opposite manner when used in water: it lags while passing over a hard object and advances when scanning the gelatinous surface of a biological membrane.

Researchers deposited the membrane and viruses on a sheet of mica. Tests showed the differing properties of the inner and outer sides of the membrane and details about the latticelike protein structure of the membrane. Findings also showed the different properties of the balloonlike head, stiff collar and hollow tail of the Phi29 virus, called a bacteriophage because it infects bacteria.

Original Publication:

Melcher J, Carrasco C, Xu X, Carrascosa JL, Gómez-Herrero J, José de Pablo P, Raman A. (2009): Origins of phase contrast in the atomic force microscope in liquids. Proc Natl Acad Sci U S A. 2009 Aug 18;106(33):13655-60. Epub 2009 Aug 5.

Researchers in the United States and Spain have discovered that an atomic force microscope - a tool widely used in nanoscale imaging - works differently in watery environments, a step toward better using the instrument to study biological molecules and structures. The researchers demonstrated their new understanding of how the instrument works in water to show details of the mechanical properties of a virus called Phi29. The images in "a" and "c" show the topography, and the image in "b" shows the different stiffness properties of the balloonlike head, stiff collar and hollow tail of the Phi29 virus, called a bacteriophage because it infects bacteria. (C. Carrasco-Pulido, P. J. de Pablo, J. Gomez-Herrero, Universidad Autonoma de Madrid, Spain)

Researchers in the United States and Spain have discovered that an atomic force microscope - a tool widely used in nanoscale imaging - works differently in watery environments, a step toward better using the instrument to study biological molecules and structures. The researchers demonstrated their new understanding of how the instrument works in water to show details of the mechanical properties of a virus called Phi29. The images in "a" and "c" show the topography, and the image in "b" shows the different stiffness properties of the balloonlike head, stiff collar and hollow tail of the Phi29 virus, called a bacteriophage because it infects bacteria. (C. Carrasco-Pulido, P. J. de Pablo, J. Gomez-Herrero, Universidad Autonoma de Madrid, Spain)

http://news.uns.purdue.edu

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Spectroscopy Meeting

Juli 29, 2009

Thermo Fisher Scientific will hold its 2009 Spectroscopy User Meeting from September 14-15, 2009 in Stratford, UK. The event will cover an evening applications workshop on September, 14 and a free of charge scientific programme on September, 15. The scientific programme will feature talks from spectroscopy instrument users. In addition applications specialists will be providing an update on recent advances in the use of infra-red, near infra-red, Raman and UV spectroscopy. There will also be the opportunity to see current generation spectroscopy systems in operation and see how sample handling and data analysis tools have changed over the years.
www.thermo.com/ukscievents


Routine Spectroscopy in Analytical Labs

Mai 14, 2009

Thermo Fisher Scientific will host a series of free informative seminars on routine spectroscopy in the analytical laboratory. This seminar will explain the range of spectroscopic techniques currently available for use in the quality control or analytical laboratory. The essential theory of Infra-Red, Near-Infra-Red, Raman and UV spectroscopy will be covered, together with how to select the best technique for a given process or application. The seminar is aimed at scientists and analysts looking to commission, expand or replace spectroscopic analytical capabilities in their laboratory.
Dates are:
June 2, 2009 – Hemel Hempstead, UK
June 3, 2009 – Leeds, UK
June 4, 2009 – Edinburgh, UK

Attendance is free of charge. For registration visit:
www.thermo.com/ukscievents


Distinguishing Single Cells With Nothing But Light

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.
www.rochester.edu

IRAM scattering data from a single granulocyte.

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.

IRAM scattering data from a single lymphocyte. Clear differences are visible when compared to data from a granulocyte.


Seminar on Raman Spectroscopy

März 9, 2009

Thermo Fisher Scientific will host a free of charge informative seminar on the increasingly popular and implemented Raman spectroscopic technique. The seminar will be held on April 23, 2009 in Hemel Hempstead, UK. It is aimed at scientists looking to expand their analysis capabilities in either routine or research laboratories. Attendees will have the opportunity to see Raman systems in operation and the opportunity to ask questions about specific applications. For registration please visit:
www.thermo.com/ukscievents


International Nanoscience Conference

Februar 16, 2009

Veeco Instruments has announced it will host the seventh „Seeing at the Nanoscale“ conference at the University of California, Santa Barbara (UCSB), July 28-31, 2009. The conference provides a forum for academic and industrial scientists to share information and exchange ideas on advanced nanotechnology topics, ranging from novel imaging approaches and unique material characterization to combining atomic force microscopy (AFM) with other technologies, such as confocal microscopy and raman spectroscopy. This year there is also a special session on emerging AFM markets, such as energy generation, storage and conservation.
www.veeco.com/nanoconference
www.ucsb.edu


Focus on Microscopy 2009

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:
www.focusonmicroscopy.org

Krakow, Poland, source: pixelio.de

Krakow, Poland (source: pixelio.de)