Special Seminar - Nano-rheology of biomolecules

Event Date: 

Thursday, March 12, 2015 - 11:00am to 12:00pm

Event Location: 

  • Elings Hall 1605

Event Contact: 


Amila Ariyaratne, graduate student at UCLA


For biochemists, proteins are folded polymer structures catalyzing reactions with certain rates, binding constant to other molecules, etc. As physicists, we want to study the material properties of these large but compact molecules. The basic questions that can be asked include: do proteins behave as elastic elements when deformed with a constant force? What should we expect if we deform proteins with an oscillatory force?

In his talk, he will discuss two unique experiments that he performed to address these questions. In one of the approaches, the group used an electric field to exert a force (in the pico Newton range) on a protein and measured the deformation of the protein with sub-Angstrom resolution using evanescent wave scattering. They were able to observe the effect of temperature on the materials properties of the protein for the first time (for proteins in the native state), and also infer new information about the hydration shell of a protein.

The other experiment is conceptually similar, but uses a different experimental setup and a different molecule, namely a voltage gated ion channel. Here, the deformation of the protein can be gauged by measuring the ionic current through the channels.

In addition, he will also present some interesting detours that he took along the way, including a possible new bio-sensor platform using LSPR, as well as a new ion channel construction for the artificial regulation of ion channels.