Lectures & Events

Chemical and Biological Physics Guest Seminar

Monitoring life in action—as it occurs in real time within the cellular cytoplasm at the relevant single molecule scale—remains an important challenge. In order to see life unravel and monitor specific biomolecules as they diffuse and assemble in the cytoplasm, we create contrast with the cellular background by fluorescently labeling biomolecules. Yet the diffraction limit of light naively keeps us from peering into length scales comparable to those of single molecules. For this reason, the 2014 Chemistry Nobel Prize was awarded for separating signals from particles in time that cannot otherwise be separated in space to localize biomolecular structures to a precision beyond the diffraction limit. However, this process is slow and thus we compromise temporal resolution by separating signal in time. Here we present new Mathematics that make it possible to consider complex dynamical signals from which we can build a story of life in action starting from single, or very few, photons. The methods we present—motivated by the tools of Bayesian nonparametrics—show us how to achieve diffraction-limited tracking from signal previously considered insufficient. If time allows, we will discuss extensions of our methods to inferring diffusional dynamics from single photon arrivals from confocal imaging methods Dept of Physics, Arizona State University