Condensed Matter Physics Seminar: Single molecules under confinement

Abstract:

Fluorescence microscopy is a powerful tool to investigate various biological and physical aspects of the micrometer and nanometer scales. The use of nano-channels arrays in combination with fluorescence microscopy has been shown to enable high-throughput genomic analysis at the single-molecule level. 

In this talk, I will present two works using these nano-channels arrays to experimentally improve the ability to localize single fluorescent molecules and thus extract more accurate and sensitive data.

The first part of the talk will focus on the limiting factor of optical DNA mapping inside nano-channels. This limitation is not the optical resolution as usually referred, but the thermal fluctuation of the DNA molecule in the channel. Moreover, I will present a method to increase the mapping accuracy by time averaging over the fluctuations.  

In the second part, I will show an experiment where the same nano-channels are used as “nano-tracks” to confine the diffusion of fluorescent synthetic nano-machines to one dimension, and thus increasing their fluorescence signal. In this experiment we ask whether sufficient amount of work could be exerted by a molecular motor to propel “nano-submarines”, and overcome the dominant viscosity forces in the extremely low Reynold’s number regime found in the nano-meter scales.

Seminar Organizer: Prof. Sasha Gerber