Label-free Vibrational Imaging Techniques for Applications in Biological and Chemical Analysis

This project is in the exciting interdisciplinary area of label-free imaging and its applications in biological and chemical analysis. Current techniques used in biology either do not give molecule (chemical) specific information or rely on tagging fluorophores/dyes to enable visualisation and in addition, are invasive and/or destructive. In electrochemistry/catalysis while bulk (ensemble averaged) phenomenon is measured, local changes on surfaces are not visualised due to lack of complementary and chemical specific imaging techniques. In this project the aim is to develop vibrational 'chemically selective' imaging techniques for bio-(electro)-chemical applications. Techniques based on coherent Raman scattering (CRS), which are vibrational finger-printing techniques, and much more powerful than conventional spontaneous Raman spectroscopy will be used. In CRS the signals are much stronger to allow in situ real-time imaging yet can be as informative and chemically selective as Raman spectroscopy. Thus, the ability to do chemically selective imaging at the typical sub-micron (or lower) spatial resolution of CRS techniques can yield an advanced understanding of phenomena at bio-electrochemical interfaces such as tethered membranes, new electrode materials and catalytic surfaces, respectively. Thus in this project applications of our recently developed chemically selective micro-/nano-scopic CRS imaging techniques will be explored to demonstrate their utility in bringing about a step change in our understanding of chemical phenomena occurring at liquid-solid interfaces.