DoD basic research discovers new spectroscopic signatures from the "stuff of life"

Physics professor Elliott Brown and graduate student Anna Lukawska work in the lab on nanobiological characterizations.

http://phys.org/news/2012-05-dod-basic-spectroscopic-signatures-life.html

Naturally, DNA sensing and identification has become a very important technology in such areas as biology, medicine and law enforcement. But positive identification without ambiguity is difficult because DNA is so sparse in the human organism and because it shares many of the same chemical bonds as other more common biomolecules–proteins and polysaccharides.

So traditional spectroscopic methods, such as infrared transmission, cannot distinguish DNA from these other molecules. More elaborate techniques are necessary, such as polymerase chain reaction (PCR) followed by gel electrophoresis, which are expensive and time-consuming.

Fortunately, the large size of DNA molecules makes them amenable to other spectroscopic methods in the THz region of the electromagnetic spectrum–a region well below the infrared in frequency but well above common radio and radar frequencies.

Wright State University researchers led by physics professor Elliott Brown have been investigating these unique THz DNA signatures through a Multidisciplinary University Research Initiative (MURI) funded by the U.S. Army Research Office. Their multi-year $600,000 grant has recently identified several unique and surprisingly strong signatures from DNA molecules between 0.7 and 1.0 THz.

“The surprise is that we have recently measured these DNA signatures under physiological conditions in which the DNA was suspended in an aqueous buffer solution very similar to that in living cells,” Brown said. “Previously, the strong THz absorption by liquid water was thought to be too strong to observe signatures from any suspended molecular species.”

So far, Brown said, the signatures appear unique to the DNA molecule at hand, be it single-stranded or double-stranded DNA.

“The caveat is that so far we have only observed relatively short DNA strands well under the length of the human genome,” he said. “But we are moving in that direction.”

The research project is headed by the University of California-Irvine, and along with Wright State University has collaborators at Marshall University, Yale University and the University of Chicago. The MURI Grant funds the research for up to five years.

Marshall Physics Professors Receives Research Grant from NASA

MY NOTE: THE EVER DEVELOPING SCIENCE INVOLVING THz, CONTINUES TO INCREASE AND AMAZE ME. IT'S UNFORTUNATE, I DON'T HAVE THE TECHNICAL BACKGROUND TO HELP READERS SORT THROUGH AND BETTER UNDERSTAND ALL OF THESE DEVELOPMENTS.  THIS CAUGHT MY EYE, AS IT MAKES REFERENCE TO COHERENT TERAHERTZ ACOUSTIC PHONONS, FOR USE IN DEEP SPACE ROCKET PROPULSION SYSTEMS. WISH I HAD A CLUE ABOUT THE BASICS TO SHARE, BUT I DON'T. AS ALWAYS WOULD APPRECIATE ANY COMMENTARY, AND STILL WAITING ON SEVERAL PROMISED POSTS.

http://www.huntingtonnews.net/12589
HUNTINGTON, W.Va. – Marshall University physics professor Dr. Thomas Wilson has been awarded $478,709 to conduct research to help improve the propulsion systems NASA uses for deep-space missions.

The three-year award was one of 28 made nationally this summer through the NASA EPSCoR program. Wilson submitted the proposal through the NASA West Virginia Space Grant Consortium. His project is titled “Coherent Terahertz Acoustic Phonons: A Novel Diagnostic for Erosion in Hall Thruster Discharge Chamber Walls.”

According to Wilson, NASA uses a special type of propulsion – electromagnetic (Hall) thrusters – for deep-space missions. These missions may last for many years as spacecraft move around the solar system; however, the wall structure of the thrusters is subject to erosion over time. The goal of his research is to better understand this erosion process and potentially improve the future design of these propulsion systems.

“The proposed work aims to significantly advance our fundamental knowledge base for these erosion processes and has the potential to lay the groundwork for intelligent selection and design of materials with improved erosion resistance that would increase thruster operational lifetime,” Wilson said.

He said the findings may eventually bring cost savings to NASA in thruster testing and design. 

Wilson’s collaborators include physicists and electrical engineers at NASA Glenn Research Center (GRC) in Cleveland; at the universities of Michigan, Rice and Stuttgart; and at Rensselaer Polytechnic Institute.

Marshall physics students also will collaborate on the project. The award provides research stipends for Marshall undergraduate physics majors. Hall thruster testing, research and development at GRC started in the 1990s, and Wilson hopes to take his undergraduate research assistants to the center to participate in the research project.

In addition, Wilson says his GRC collaboration should allow Marshall students pursuing master’s degrees in physical science to compete successfully for NASA Graduate Student Researchers Program fellowships, which are awarded for one year as training grants in the amount of $30,000.