Impact of Raman Microscopy on Biomedical Research (original) (raw)

Marinella SANDROS Raman spectroscopy is a vibrational technique complimentary to Infrared (IR) Absorption. They both provide information on materials via their molecular and crystalline vibrations. While IR spectroscopy has been used more widely, Raman has some distinctly different characteristics that provide advantages when making measurements on biological materials. For a start, water, while it does produce a spectrum, that spectrum is weak and does not present an overwhelming background as it does in the IR; since biological matrices are, by definition, aqueous, this is an enormous advantage. The second important difference lies in the focusing capability in microscopic sampling; the physical limitations to microscopic sampling depend on the wavelength of the radiation. Raman spectra are excited by lasers with wavelengths between 1064 and 244 nm which are 4 to 400 times shorter than the wavelengths probed by infrared absorption. An IR microscope can acquire spectral maps of his...