Suppressing Brownian motion of individual molecules in solution

PHYS 504

Adam Cohen,, Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138 and W. E. Moerner,, Department of Chemistry, Stanford University, Stanford, CA 94305-5080.
The Anti-Brownian Electrokinetic Trap (ABEL trap) provides a means to trap and manipulate individual nanoscale objects in solution. The ABEL trap uses active electrokinetic feedback to cancel the Brownian motion of a single object of interest. We have trapped single molecules of DNA, proteins, viruses, lipid vesicles, and semiconductor nanocrystals. Due to its non-perturbative nature, the ABEL trap allows detailed studies of the conformational dynamics of single molecules of λ-DNA in their equilibrium, unstretched state. We identify the conformational normal modes, characterize their dynamics, and detect signs of nonlinear hydrodynamic coupling between modes--an effect present in the underlying equations of polymer dynamics but neglected in the Rouse and Zimm approximations. See: PNAS, 103, 4362-4365, 14 March 2006.

Poster Session
7:30 PM-10:00 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster

8:00 PM-10:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Sci-Mix

Division of Physical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006