My project this summer has two parts: to set up and calibrate a new Raman spectroscopy system in the biomedical-optics lab and to investigate the potential of Raman spectroscopy as a method of detecting changes in protein structure following tissue heating for the purposes of monitoring thermal therapy. Scattering of photons by atoms or molecules occurs through either elastic (Rayleigh) or inelastic (Raman) scattering. In Raman scattering, two scattering events can occur: Stokes scattering where the photon scatters off the molecule with a higher energy than the incident energy or anti-Stokes scattering where it will scatter with a lower energy. Raman spectroscopy has been shown to provide information about the structure of molecular constituents in tissues. In Raman spectroscopy a diode laser (for this project, emitting light at 785nm) is used as the excitation source. The scattered light from the sample is focused onto a fiber optic bundle which is connected to a liquid nitrogen cooled charge coupled device (CCD) for detection. The Raman spectra is then analyzed using various computer programs.

 While heating, tissue undergoes changes in protein structure. There is evidence that Raman spectroscopy could be used to detect these changes, meaning that while patients are undergoing laser thermal therapy the level of tissue damage could be monitored. The main goal for this project is to investigate if Raman spectroscopy can in fact detect changes in protein structure following tissue heating by analyzing the Raman spectra of various tissue samples heated at different temperatures.

 As new optical techniques are developed there are still many unanswered scientific questions related to the technology involved. This method has high potential as a monitoring tool for thermal therapy and hence a possible future in clinical applications therefore getting a better understanding of this technology is important.

 So far my project has consisted mostly of setting up and calibrating the new system. Learning about Raman spectroscopy and the inner workings of this technology has been exciting and I’m looking forward to starting measurements on tissue samples.