Moving polymers through pores

July 13, 2010

College Park, MD (July 13, 2010) -- The movement of long chain polymers through nanopores is a key part of many biological processes, including the transport of RNA, DNA, and proteins. New research reported in The Journal of Chemical Physics, which is published by the American Institute of Physics, describes an improved theoretical model for this type of motion.

The new model addresses both cylindrical pores and tapering pores that simulate the α-hemolysin membrane channel. "Current models do not take into account the motion of the polymer inside the pore," says author Anatoly Kolomeisky of Rice University. "The leading monomer can move back and forth many times before it finally crosses the line to the other side of the membrane. Not accounting for this behavior introduces errors into predictions."

By improving the boundary conditions for polymer movement inside the pore, researchers demonstrated a significant increase in total time in the pore compared to earlier models. In modeling a tapering pore, they confirmed that translocation occurs faster when the polymer enters the wide side of the pore.

Possible technological applications include advances in DNA sequencing and the development of biosensors using membranes. "To design an effective sensor, it is essential to understand what you are observing and how the molecule reaches the detector," says Kolomeisky.
-end-
The article, "Polymer translocation through pores with complex geometries" by Aruna Mohan, Anatoly B. Kolomeisky, and Matteo Pasquali will be published in an upcoming issue of The Journal of Chemical Physics. See: : http://jcp.aip.org/

Journalists may request a free PDF of this article by contacting jbardi@aip.org

NOTE: An image is available for journalists. Please contact jbardi@aip.org

Figure Caption: "Typical Configurations of Polymer Translocation through Nanopores. Courtesy of Aruna Mohan, Rice University."

ABOUT THE JOURNAL OF CHEMICAL PHYSICS

The Journal of Chemical Physics publishes concise and definitive reports of significant research in methods and applications of chemical physics. Innovative research in traditional areas of chemical physics such as spectroscopy, kinetics, statistical mechanics, and quantum mechanics continue to be areas of interest to readers of JCP. In addition, newer areas such as polymers, materials, surfaces/interfaces, information theory, and systems of biological relevance are of increasing importance. Routine applications of chemical physics techniques may not be appropriate for JCP. Content is published online daily, collected into four monthly online and printed issues (48 issues per year); the journal is published by the American Institute of Physics. See: http://jcp.aip.org/

ABOUT AIP

The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.

American Institute of Physics

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