New download example available for WMOSS software.

Example data and parameter files for the WMOSS software tutorial.


One example parameter file for each of the theoretical models provided by the WMOSS software.

SEE Co Activity Log

February 18 -21, 2010 – Ursinus College

Dr. Tom Kent spent the last three days working at lab of Prof. Codrina Popescu in the Chemistry Dept. of Ursinus College, Collegeville, Pennsylvania, USA. Ursinus College is a small, liberal arts college just northwest of Philadelphia. Prof. Popescu purchased a SEE Co 5K Closed Cycle He gas Refrigerator (CCR) Mossbauer system in 2005. She is able to pursue federally funded research with only undergraduate student research assistants. This is partially due to to ease of use of the SEE Co CCR Mossbauer system which uses no liquid cryogens. The student do not have to transfer liquid Helium or liquid Nitrogen which greatly reduces the risk of operating the cryogenics. The CCR Mossbauer cryostat in operation is shown below.

The cryostat features a convenient top-loading sample chamber with the sample immersed is a variable pressure, static He gas. Temperature control over a range of 5K to 32K is accomplished via heaters and Silicon diode temperature sensors located both at the top of the CCR cold finger and on the sample positioner. A SEE Co WTC102 temperature controller provides two closed loop PID 50 Watt control loops. Normally, the walls of the sample chamber are maintain at the desired temperature and the sample temperature monitored with the sensor on the sample positioner. This method avoids temperature gradients that can be generated when heating with the heater mounted on the Copper sample mount. Also the iso-thermal He exchange gas will permeate powder samples which may have ill-define thermal conductivity.

Dr. Kent's visit was an annual inspection / maintenance procedure that is part of the service contract purchased by Prof. Sorescu. Given the limited technical support available at Ursinus College, Prof. Sorescu finds an annual service contract an efficient and convenient method to keep her system in good condition and up to date.February 8 & 9, 2010 SEE Co, Edina, MN USA

Dr. Charles Johnson, Space Institute, University of Tennessee, visited SEE Co. to receive training in the operation of his newly purchased MS4 Mossbauer spectrometer and in the use of the WMOSS Mossbauer spectral analysis software. Dr. Johnson's new system, including a Ritverc 50 mCi Co-57/Rh source, will ship February 22.

January 28 & 29, 2010 McGill University

Dr. Tom Kent visited the lab of Prof. Dominic Ryan in the McGill University Physics Dept., Montreal, Canada on January 28 & 29. Dr. was providing consulting services to Prof Ryan regarding the operation of his Janis Research 5K CCR Mossbauer cryostat.

Several research groups at the University of California have been funded to set up a shared Mossbauer Spectroscopy laboratory. The equipment is being installed in Prof. Steve Cramer's labs at UC Davis, Davis, California, USA. The equipment includes two SEE Co MS4 spectrometers, a Janis Research Co. SVT-400 high efficiency LHe Super Varitemp cryostat and a Janis Research Co. 9 Tesla superconducting magnet cryostat. All the equipment was purchased through SEE Co and will be install by Dr. Tom Kent. During this visit, Dr. Kent was testing the SVT400 cryostat and horizontal gamma beam MS4 Mossbauer spectrometer. The 9 Tesla system with a vertical gamma beam geometry MS4 Mossbauer spectrometer will be tested soon. The two December 1, 2009 Knox College Prof. Charles Schultz, Physics Dept., Knox College, Galesburg, Illinois, USA, has purchased a SEE Co. MS4 spectrometer. Dr. Kent visited Dr. Schultz in Galesburg to install the system and prepare for building and testing a variable temperature, vertical drive Mossbauer velocity transducer for Dr. Schultz.

Professor Lindahl's SEE Co / Janis 4K Mossbauer Spectrometer at Texas A&M University

Articles

Professor Lindahl's SEE Co / Janis 4K Mossbauer Spectrometer at Texas A&M University During the summer of 2008, the radiation safety officer at Texas A&M University stopped by my lab in the Chemistry department to inspect the Mossbauer spectrometer that I purchased last year from Janis Research and Science Engineering and Education Co (SEE Co. – formerly Web Research). During our conversation, he mentioned that he had heard that Mossbauer was a “dying technique”. I must say that I found this perception amusing since Mossbauer spectroscopy has recently become our central research tool and is providing us with unprecedented insights into the metabolism of iron in mitochondria and indeed in whole cells. Since our instrument was installed by Dr. Tom Kent in December 2008, we have used it continuously – 24/7. Indeed, its utility has been beyond our expectations such that we now plan to purchase a second instrument. About 2002, I became interested in systems biology – an emerging field that complements the more traditional biochemical approach of disrupting a cell, purifying a protein, and then studying it using, for example, Mossbauer spectroscopy. Indeed, for the past 20 years, and in collaboration with Dr. Eckard Münck (Carnegie-Mellon University), I have conducted research in this way on the Ni-Fe-S containing enzyme acetyl-CoA synthase/carbon monoxide dehydrogenase. In systems biology, one studies an intact system– in our case the mitochondrion, an organelle often called the “powerhouse” of the cell - in all of its glorious complexity. By applying Mossbauer spectroscopy to an entire organelle, we can see all of the 57Fe in the organelle, and in proportion to the amounts present. Thus, for the first time, we determined the proportion of mitochondrial Fe present as [Fe4S4] clusters, [Fe2S2] clusters, heme Fe, and most interestingly, nonheme mononuclear Fe (see Ref 1). This last species has been especially difficult to track by other methods; but by using Dr. Lindahl and graduate student Ren Miao admiring our Mossbauer instrument. 4.2 K Mossbauer spectra of isolated mitochondria from cells replete (A) and depleted (B and C) in a ferredoxin that is required for Fe/S cluster and heme biosynthesis. In (C), nonheme mononuclear ferrous ions have been oxidized by the O2 in the growth medium, accumulating as aggregated ferric nanoparticles. Figure adapted from ref 2. Mossbauer spectroscopy, we can observe it and determine its concentration in mitochondria. Mononuclear nonheme Fe plays important roles in cell biology. Once imported into the cell, Fe ions are “earmarked” for different functions and for different compartments of the cell, resulting in bewildering and complex traffic patterns that no one currently understands. Using Mossbauer spectroscopy, we can at least now see these patterns and start to deconvolute them. These targeted nonheme mononuclear Fe ions are used as feedstock for many cellular processes, e.g. heme and Fe/S cluster biosynthesis. Nonheme mononuclear Fe also plays some “bad” roles in cell biology, for example in generating reactive oxygen species that cause mutations in the DNA and contribute to aging. In some diseases, including Friedrich’s Ataxia, X-linked Sideroblastic Anemia with Ataxia, and Parkinson’s disease, nonheme mononuclear Fe accumulates in the mitochondria, exacerbating the symptoms of these diseases. The spectrum shown reveals aggregated ferric nanoparticles in a sample that mimics one such diseased state. Our future plans are to better understand Fe trafficking in cells and to understand on a mechanistic level why Fe accumulates in these diseased states. In all of these studies, I have no doubt that Mossbauer spectroscopy will play a central role, and I thank both Tom Kent of SEE Co, and Janis Research, for manufacturing these incredible instruments. References “Electron paramagnetic resonance and Mossbauer spectroscopy of intact mitochondria from respiring Saccharomyces cerevisiae” Brandon N. Hudder, Jessica Garber Morales, Audria A. Stubna, Eckard Münck, Michael P. Hendrich, and Paul A. Lindahl, 2007, J. Biol. Inorg. Chem. 12, 1029-1053. EPR and Mossbauer Spectroscopy of Intact Mitochondria Isolated from Yah1p-depleted Saccharomyces cerevisiae” Ren Miao, Marlène Martinho, Jessica Garber Morales, Hansoo Kim, E. Ann Ellis, Roland Lill, Michael P. Hendrich, Eckard Münck and Paul A. Lindahl, 2008 Biochemistry, 47, 9888-9899

SEECO Mossbauer Spectroscopy Cryogenics Gamma-ray Sources FORTRAN

SEE Co. (formerly WEB Research Co.) offers hardware, software and Ritverc Gamma-ray sources for Mossbauer Spectroscopy. We specialize in turn-key systems complete with installation, training and extended service contracts.

New products and services will be added in 2009. The first of these will be a dual-channel PID temperature controller.

We will be updating this site frequently. Please check back often.

Thanks,

Tom Kent,
Pres.SEE Co.
Edina, Minnesota, USA

Mossbauer Spectroscopy Cryogenics Gamma-ray Sources FORTRAN