conference

2012/05/16 Speaker:Prof. Chia-Fu Chou Topic:The Surprising Effects of Nanoconfinement on Biosensing, Polymer Dynamics, and Bacterial Cytoskeletal Oscillators

date:2012-05-14

announcer:Wen-chi Lin

SpeakerProf. Chia-Fu Chou

TopicThe Surprising Effects of Nanoconfinement on Biosensing, Polymer Dynamics, and Bacterial Cytoskeletal Oscillators

Date5/16 15:30~17:20

Location: 博雅101

Chairman: Prof. Chi-Sheng Wu


The Surprising Effects of Nanoconfinement on Biosensing, Polymer Dynamics, and Bacterial Cytoskeletal Oscillators

Chia-Fu Chou (周家復)

Institute of Physics; Genomics Research Center; Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan

E-mail: cfchou@phys.sinica.edu.tw

http://www.phys.sinica.edu.tw/~nanobio/

 

Given its simplicity in fabrication, nanofluidic confinement, in the forms of nanoslits, nevertheless offers unique platforms for the study of molecular or cellular biophysics [1]. We demonstrated a nanoslit sensor platform [2] with spatiotemporally resolved reaction kinetics, by taking advantage of the highly reduced diffusion length provided by nanoslits which enhances the collision rate between the target analyte and probe sensors. Meanwhile, a variation of electrodeless dielectrophoresis [3] has been developed into a protein enrichment methodology, called nanoscale molecular dam [4]. We also established an entropy-driven single DNA tug-of-war (TOW) system composed of two micro-nanofluidic interfaces bridged by a nanoslit. This surprisingly simple system enables us to study polymer TOW and the conformation recovery through entropic recoiling, without using sophisticated external force apparatus such as optical tweezers, magnetic tweezers, and atomic force microscopy [5]. Further, the remarkable oscillations of the bacterial cytoskeletal MinCDE system, to perform accurate and symmetric septation in bacterium E. coli, may also be modulated by nanoconfinement. We cultured E. coli under strong nanofluidic slit-like confinement of 400 nm channel depth, to mimic various curvature changes of cell peripherals. Interestingly, bacteria are able to proliferate, but show irregular pancake-like morphology and intermittent oscillation episodes were observed in MinDE dynamics. The transitions between intermittent episodes display period-doubling signature of bifurcation by analyzing image series via spatial time-frequency method.

 

References:

[1]         L.J. Guo, X. Cheng, C.F. Chou. Nano Lett. 4, 69 (2004); J. Gu, R. Gupta, C.F. Chou, Q. Wei, F. Zenhausern. Lab Chip 7, 1198 (2007).

[2]         T. Leïchlé, Y.L. Lin, P.C. Chiang, K.T. Liao, S.M. Hu, C.F. Chou. Sens. Actuators B 161, 805 (2012).

[3]         C.F. Chou et al. Biophys. J. 83, 2170 (2002); C.F. Chou, F. Zenhausern. IEEE Eng. Med. Biol. Mag. 22, 62 (2003).

[4]         K.T. Liao, C.F. Chou. J. Am. Chem. Soc. (Comm.) (2012), in press.

[5]         J.W. Yeh, A. Taloni, Y.L. Chen, C.F. Chou. Nano Lett. 12, 1597 (2012). (Highlighted by Nature, http://www.nature.com/nature/journal/v482/n7386/full/482442b.html)

 

 

Chia-Fu Chou Bio:

Prof. Chou earned his B.S. in physics from National Tsing Hua University (Hsinchu) in 1986, and Ph.D. in physics from State University of New York at Buffalo in 1996. From 1997-2000, he was a NIH postdoctoral fellow at Princeton University (in physics and molecular biology). In 2000, he joined the Solid State Research Center of Motorola Labs in Tempe, AZ, as a Lead Scientist, and later promoted to Principal Staff Scientist in 2001. In late 2002, he co-founded the interdisciplinary Center for Applied Nanobioscience in Biodesign Institute at Arizona State University, and served as an Associate Professor and Principal Investigator. Since Spring 2006, he has been a Senior Research Fellow (Professor) at Institute of Physics with affiliation at both Genomics Research Center and Research Center for Applied Sciences at Academia Sinica, Taipei, Taiwan. His current research interests include single molecule and cellular biophysics, micro- and nanofluidics, and super-resolution imaging.