Event Scheduled for Oct 19, 2012
Event: ME Fall 2012 Seminar Series ‘Squeezing DNA: Properties of a Semi-flexible Polymer in Strong Confinement’ Yeng-Long Chen, Institute of Physics, Academia Sinica, Taiwan
Location: UTEB 150
Time: 02:00 pm
Details of Event:
Abstract: DNA molecules are linear, semiflexible macromolecules that fit inside a micron-sized nucleus, yet fully extend up to meters. Their conformation and dynamics within strong confinement influence how biological machinery operate in the cell. With scaling theory, Brownian dynamics simulations and single molecule experiments, we probe how DNA properties change as they become confined in quasi-two dimensional slits and quasi-one dimensional tubes. When the confinement size is smaller than the DNA radius of gyration but larger than the persistence length, we find that scaling theory predicts the dependence of DNA size and diffusivity on confinement. As the confinement length becomes comparable and smaller than the DNA persistence length, interesting changes occur in the polymer conformation in the slit and the tube, leading to effectively lower DNA elasticity. Polymer relaxation inside the tube also becomes strongly restricted. Finally, entropic elastic forces are measured for DNA in tug-of-war between two nano-micro channel interfaces.
Biographical Sketch:
Yeng-Long received his undergraduate degree in Chemical Engineering from Caltech in 1998 and his Ph.D. in Chemical Engineering from UIUC in 2003. In 2006, He joined the Institute of Physics at Academia Sinica, a premier national research institution of Taiwan. His research program investigates the thermodynamic and dynamic properties of polymers, DNA, and soft particles in micro- and nano-fluidic systems using theoretical, simulation, and experimental tools. In 2011, he joined the Department of Physics of National Taiwan University as an adjunct faculty and the Department of Chemical Engineering of National Tsing-Hua University as an joint faculty. His research work has been recognized by the Li Foundation Heritage Award and the Academia Sinica Career Development Award. He is currently on sabbatical in the Department of Materials Science, MIT.
Target Audience: Open to All
Sponsored By: Mechanical Engineering
Pamphlet/Flyer:
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