Biophysics and Nanoscience

Title: Single Molecule Biophysics Lab
Faculty Mentor: Dr. Ahmed Touhami

We are interested in developing and applying new technologies for detecting, tracking, and manipulating single molecules in living cells. In particular we are combining optical trapping (OT) and single molecule fluorescence (SMF) with real-time observations of the dynamic behavior of single proteins, to determine the mechanisms of action at the level of an individual molecule, and to explore heterogeneity among different molecules within a population. This highly multidisciplinary project provides numerous research and training opportunities for undergraduate students and teachers to work at the interface of physics, chemistry, biology, and nanotechnology. Specific projects for participants include membrane protein dynamics, the investigation of bacterial cell division dynamics at the single molecule level, and mechanics of biological filaments, the exploration of the dynamics and mechanics of bacterial pili filaments using OT and SMF. In the latter project the aims are to understand: How these soft nanomachines move, bind, and unbind, how their mechanical properties are affected by changing physiological and environmental conditions, and how the bacteria manipulate them to penetrate mammalian host cells. A third project concerns folding and aggregation of proteins. Participants will learn how to measure forces holding the protein complex by pulling the complex apart using dual-optical trapping technique in order to investigate protein misfolding time scales, dynamics, and misfolded states.

Title: Superlattice structures for sustainable thermal energy harvesting
Faculty Mentor: Dr. Karen Martirosyan

Thermoelectric (TE) materials that generate electricity from waste heat sources are an ideal solution to the search for sustainable energy. The ZT of a thermoelectric material is a dimensionless unit that is used to compare the efficiencies of various materials. We propose to increase ZT value of TE materials by assembling low-dimensional geometries combining single wall carbon nanotubes with layered perovskites to form superlattice periodical structures. The superlattice structures will assist to enhance the thermal phonon scattering and increasing electron mobility, which improves TE efficiency. We plan to fabricate several nanostructured complexes by using methods that we recently developed. The proposed research includes the following basic tasks: (i) identifying the stable superlattice structures for TE materials with high figures of merit ZT; (ii) producing p-type and n-type of TE matrix nanocomposites; (iii) self- assembling fabrication and testing of TE devices suitable for small-scale power system for energy harvesting. The students will be exposed to the advanced nanostructured technology development.