Hyperspectral spontaneous and nonlinear Raman imaging for biomedical applications

Chemical imaging has greatly revolutionized our ability to study complex chemical processes occurring in microscopic world with unprecedented details and thus have tremendous applications in several disciplines including chemistry, medicine and pharmacy, food science and agriculture, and biology. However, traditional chemical imaging techniques either rely on contrast-enhancing agents or are limited by a poor signal quality, a lack of chemical specificity, and sensitivity. As a part of my dissertation work, I describe non-invasive vibrational spectroscopic imaging techniques that can address the limitations of current clinical diagnostic procedures and has the potential to provide real time chemically specific information.;Vibrational spectroscopic imaging, in particular, utilizing spontaneous Raman scattering and coherent anti-Stokes Raman scattering (CARS), are successfully applied to various complex biological systems for detecting microcalcifications in a breast tissue, screening for protein crystals, distinguishing fatty acids, and detecting bacterial endospores responsible for anthrax.;The second part of my dissertation is mainly focus on details of how spectroscopic techniques can be used in conjunction with statistical tools, such as phase retrieval algorithm, principal component analysis, and cluster analysis, to arrive at more conclusive results. In these studies, the collected results show the combined potential of spectroscopic imaging and statistical tools to investigate significant problems in biological and medical sciences. This approach might one day replace traditional diagnostic procedures and open wide doors to a number of potential clinical applications.