News & Events
- Category: News
Raleigh, NC, May 19, 2013 -- Protochips (http://www.protochips.com), a company specializing in revolutionary products for in situ electron microscopy, announced that the company has been selected to receive a Tibbetts award in Washington, DC on May 16th. Presented by the United States Small Business Association, the award recognizes companies with exemplary returns from SBIR and SBA projects. The award acknowledges companies that have exceeded the expectations of the program and is based on several factors including the economic impact of the technological innovation, overall business achievement, and demonstration of effective collaborations.
Protochips is honored to be recognized with a Tibbetts award. The award is an indication of the success Protochips has achieved in developing and commercializing the Aduro technology. Aduro has risen from a novel technique for heating within an electron microscope to the market leader for in situ heating. With the success of the Aduro and Poseidon systems, Protochips has grown to over twenty employees, demonstrating the success of the SBIR program.
Protochips, located in Raleigh, NC, is a company providing revolutionary products and technologies for the in situ electron microscopy market for more than nine years. Through With their innovative E-chip™ consumable technology, Protochips is fundamentally changing the way in situ microscopy is performed. The E-chip platform is the engine that drives Protochips Aduro™ and Poseidon™ in situ solution, providing temperature and electrical in situ capabilities for Aduro and liquid in situ capabilities for Poseidon. More information can be found at http://www.protochips.com.
- Category: Events
Please join the Southeastern Microscopy Society in Greenville, SC, on May 22 through 24, 2013 for the annual meeting! The meeting will be held at the Embassy Suites Golf Resort & Conference Center which is located at 670 Verdae Boulevard, Greenville, SC.
The meeting begins on Wednesday, May 22, with two afternoon workshops that will be held on the Clemson campuses. Participants will be leaving the hotel at about 1:30. Then, at 6 PM there is a Vendor Social. The presentations are all day on Thursday, and there is a Banquet that starts at 6PM with a Social Hour and then dinner at 7 PM. The Business Breakfast (included with the registration fee) is Friday morning. There are more presentations until noon, when the meeting comes to a close.
At the Advanced Materials Research Laboratory, there will be a tour of the facility (with 3 TEMS (including a 300 kV and 4 SEMs) with an introduction to the capabilities of the microscopes there, sponsored by Hitachi, and a workshop titled “A Semiconductor-Based Heating and Electrical Biasing Platform for High-Resolution in situ Electron Microscopy”, sponsored by Protochips.
- Category: Events
Protochips (http://www.protochips.com), a company specializing in revolutionary products for in situ electron microscopy, today announced a seminar to be held on April 25th – 26th, 2013 at North Carolina State University. The seminar will begin with an overview of the Poseidon technology, lead by applications engineer Madeline Dukes, followed by two days of live demonstrations on the TEM. This seminar is open to participants worldwide regardless of affiliation.
With the development of liquid holders for TEM, electron microscopy of fully hydrated specimens is proving to be a technique that eliminates preparation artifacts while providing nanometer resolution of specimens in their native state. By maintaining the sample in its native, hydrated state, liquid cell EM enables imaging of dynamic processes such as nanoparticle growth and interactions, providing highly valuable correlative data to complement existing microscopy techniques. Applications include catalysts, nanoparticles, batteries, dispersions, gels, and living cells. In a liquid cell system, the sample is maintained between a pair of configurable sample support devices called E-chips, each with an ultra thin, electron-transparent silicon nitride membrane to create a static or flow liquid compartment at the tip of the TEM holder. Different experiments often require optimization of the flow channel, and important parameters such as channel size and volume can be varied by selecting the correct pair of sample support devices. The Poseidon TEM holder provides both 2-port, for flow and 3-port for mixing experiments. By allowing users to configure Poseidon with their choice of E-chips, the greatest flexibility and highest resolutions in liquid are possible, with nanoscale resolution through several microns of liquid. Poseidon is a self-contained TEM holder with external components that does not require any modification to existing TEMs.
- Category: News
Using a new technique, the scientists created two types of visualizations. The first included pictures of individual nanoparticles’ atomic structures at 100,000-times magnification – the highest resolution images ever taken of nanoparticles in a liquid environment.
The second visualization was a movie captured at 23,000-times magnification that revealed the movements of a group of nanoparticles reacting to an electron beam, which mimics the effects of the infrared radiation used in cancer therapies.
In the movie, the gold nanoparticles can be seen surfing nanoscale tidal waves.
“The nanoparticles behaved like grains of sand being concentrated on a beach by crashing waves,” said Debbie Kelly. “We think this behavior may be related to why the nanoparticles become concentrated in tumors. Our next experiment will be to insert a cancer cell to study the nanoparticles’ therapeutic effects on tumors.”
- Category: Events
The Moscone Center in San Francisco is once again hosting the MRS Spring Meeting. Protochips will be onsite and sharing our latest developments. We will have in our booth the Aduro 300 and Poseidon 500 and look forward to seeing you there.
- Category: Events
Protochips is pleased to attend the 2013 Lehigh Microscopy School: STEM: From Fundamentals to Advanced Applications. Protochips will be leading the in situ experiments class from 830-930 and will provide a in situ TEM demo from 945-1050. Please visit the Lehigh website for more information on this course
- Category: News
Effect of using stencil masks made by focused ion beam milling on permalloy Ni81Fe19 nanostructures
J R Bates, Y Miyahara, J A J Burgess, O Iglesias-Freire and P Grutter
2013 Nanotechnology 24 115301
Focused ion beam (FIB) milling is a common fabrication technique to make nanostencil masks which has the unintended consequence of gallium ion implantation surrounding milled features in silicon nitride membranes. We observe major changes in film structure, chemical composition, and magnetic behaviour of permalloy nanostructures deposited by electron beam evaporation using silicon nitride stencil masks made by a FIB as compared to stencil masks made by regular lithography techniques. We characterize the stenciled structures and both types of masks using transmission electron microscopy, electron energy loss spectroscopy, energy dispersive x-ray spectroscopy, magnetic force microscopy and kelvin probe force microscopy. All these techniques demonstrate distinct differences at a length scale of a 1–100 nm for the structures made using stencil mask fabricated using a FIB. The origin of these differences seems to be related to the presence of implanted ions, a detailed understanding of the mechanism however remains to be developed.
DNA bending-induced phase transition of encapsidated genome in phage λ
Gabriel C. Lander, John E. Johnson, Donald C. Rau, Clinton S. Potter, Bridget Carragher and Alex Evilevitch
Nucleic Acids Research, 2013, 1–7 doi:10.1093/nar/gkt137
The DNA structure in phage capsids is determined by DNA–DNA interactions and bending energy. The effects of repulsive interactions on DNA interaxial distance were previously investigated, but not the effect of DNA bending on its structure in viral capsids. By varying packaged DNA length and through addition of spermine ions, we transform the interaction energy from net repulsive to net attractive. This allowed us to isolate the effect of bending on the resulting DNA structure. We used single particle cryo-electron microscopy reconstruction analysis to determine the interstrand spacing of double-stranded DNA encapsidated in phage λ capsids. The data reveal that stress and packing defects, both resulting from DNA bending in the capsid, are able to induce a long-range phase transition in the encapsidated DNA genome from a hexagonal to a cholesteric packing structure. This structural observation suggests significant changes in genome fluidity as a result of a phase transition affecting the rates of viral DNA ejection and packaging.
Structural visualization of key steps in human transcription initiation
Yuan He, Jie Fang, Dylan J. Taatjes & Eva Nogales
Nature (2013) doi:10.1038/nature11991
Eukaryotic transcription initiation requires the assembly of general transcription factors into a pre-initiation complex that ensures the accurate loading of RNA polymerase II (Pol II) at the transcription start site. The molecular mechanism and function of this assembly have remained elusive due to lack of structural information. Here we have used an in vitro reconstituted system to study the stepwise assembly of human TBP, TFIIA, TFIIB, Pol II, TFIIF, TFIIE and TFIIH onto promoter DNA using cryo-electron microscopy. Our structural analyses provide pseudo-atomic models at various stages of transcription initiation that illuminate critical molecular interactions, including how TFIIF engages Pol II and promoter DNA to stabilize both the closed pre-initiation complex and the open-promoter complex, and to regulate start--initiation complexes, combined with the localization of the TFIIH helicases XPD and XPB, support a DNA translocation model of XPB and explain its essential role in promoter opening.