Invited Paper IPF-MoM1
Trapping Single Molecules in Water at Room Temperature

Monday, October 20, 2008, 8:20 am, Room 312

To study a single molecule, one would like to hold the molecule still, without perturbing its internal dynamics. I will present a machine that achieves this goal. The Anti-Brownian Electrokinetic trap (ABEL trap) tracks the Brownian motion of a single molecule using fluorescence microscopy, and applies electrical kicks to the molecule that are timed to induce an electrokinetic drift that cancels the Brownian motion.¹ The ABEL trap can immobilize single biomolecules for extended observation and has been used to study the dynamics of individual DNA molecules and protein chaperonins.² I will give examples of new things that can be learned from trapped molecules.³

¹ A. E. Cohen and W. E. Moerner, “Suppressing Brownian motion of individual biomolecules in solution,” Proc. Natl. Acad. Sci. USA 103, 4362-4365 (2006).
² A. E. Cohen and W. E. Moerner, “Principal Components Analysis of shape fluctuations of single DNA molecules,” Proc. Natl. Acad. Sci. USA 104, 12622-12627 (2007).
³ A. E. Cohen and W. E. Moerner, “Controlling Brownian motion of single protein molecules and single fluorophores in aqueous buffer,” Opt. Express 16, 6941-6956 (2008).