While two-dimensional infrared (2DIR) spectroscopy has been useful for studying properties of peptides and proteins, many of those results were made on “clean”, homogenous samples. My lab’s long-term goal is to turn the sensitive and ultrafast observables of 2DIR into useful image contrast agents for complex biophysical systems, where they can answer questions related to solvation dynamics and molecular structure that few other imaging methods can address. To that end, I will present three projects from my lab that move us closer to this goal.
Semiconducting nanostructures have been proposed as material platforms for a wide variety of photonic, electronic, and photovoltaic elements. In order to realize these applications, careful design and characterization of electronic properties such as dopant concentration, activation, and distribution are needed. I will discuss the use of near-field optical microscopy as a non-destructive method for chemical, structural, and electronic imaging in nanomaterials, focusing on a specific application, the study of axially-doped silicon nanowires (SiNWs).
Linear and non-linear vibrational spectroscopy provides a powerful tool to probe the structure and conformational dynamics of nucleic acids. In the first part of my talk, I will describe our recent progress on the modeling of vibrational spectra of nucleic acids. We have developed vibrational frequency maps and coupling models that allow one to calculate the vibrational Hamiltonian, and thus the vibrational spectra, of nucleic acids in the base carbonyl stretch region directly from MD simulations.
Abstract: Cell heterogeneity plays a critical role in many pathophysiological processes such as cancer development and neurodegeneration. However, phenotypic variations of individual cells in a complex organ are often intractable by traditional analytical techniques. The main obstacles are the limited amount of analytes in a single cell and the need for noninvasive in situ analysis in order to preserve cell function and microenvironmental information.