Anasys Instruments proposes to develop an optical platform that combines confocal Raman spectroscopy with infrared spectroscopy with sub-micron spatial resolution on a single optical microscope based platform (patents pending). Infrared spectroscopy and Raman spectroscopy are separately extremely successful and complementary techniques for chemical composition analysis. Infrared spectroscopy characterizes samples by detecting absorption of infrared light by dipole moment changes induced in molecular bond vibrations. Raman spectroscopy detects scattered light that wavelength shifted by a sample due to molecular vibrations that induce changes in polarizability. The techniques are highly complementary because molecular vibrations that are strong IR absorbers are typically weak Raman scatterers and vice versa. Conventional IR spectroscopy has two significant limit fundamental limitations: (1) spatial resolution limited by optical diffraction from its longer wavelengths to the scale of many microns; (2) sample preparation is often complex, requiring preparation of thin IR transparent samples. These limitation, along with sample preparation complexities have limited applicability of IR spectroscopy in many life sciences applications. Differences in IR and Raman wavelength ranges, light sources and detectors have also made it impossible to obtain IR and Raman spectroscopy from the same sample region. As a result, there is no currently available instrument that can perform infrared and Raman analysis on the same sample with sub-micron spatial resolution for both techniques. We propose to overcome this limitation developing and demonstrating the applicability of the IRaman platform which will provide simultaneous and complementary IR and Raman analysis in the same instrument. This project will leverage the recent invention of sub-micron photothermal IR spectroscopy, a technique that uses a tightly focused visible laser to probe the infrared absorption on a scale ~10X smaller than the IR optical diffraction limit. Complementary Raman measurements will be obtained by using the same visible laser beam in combination with a Raman spectrometer to excite and detect Raman scattering in the sample. A Prototype instrument will be built to demonstrate utility of simultaneous IR/Raman technique in a couple of high value biomedical applications. Anasys has extensive experience in successful commercialization of breakthrough IR analysis products based on photothermal physics Anasys Instruments Proprietary and Confidential 1
Raman and IR spectroscopy are complementary techniques that can provide critical information about microscopic chemical composition, but to date incompatibilities between the two techniques has made it impossible to perform simultaneous IR and Raman measurements. This SBIR project will overcome the previous barrier, developing a breakthrough instrument for biomedical imaging that will enable simultaneous IR and Raman spectroscopy on the same platform while providing 10X better spatial resolution than conventional infrared spectroscopy.