Development of Near-Infrared Fourier Transform Raman Spectroscopy for the Study of Biologically Active Macromolecules

Abstract

General advantages and potential limitations of Fourier transform (FT) Raman spectroscopy using Nd:YAG laser excitation at 1064 nm have been considered for both routine analysis and specific biophysical applications. Optical design and operating parameters which affect the quality and reproducibility of the data are discussed. Moderately high resolution spectra (0.25 cm⁻¹) of liquids are obtained with relative ease, and the results are compared with dispersive spectra. Particular emphasis has been placed on applications to biological systems where intrinsic fluorescence has traditionally limited the use of dispersive Raman spectroscopy. As an example of a biophysical study, we demonstrate the utility of FT-Raman spectroscopy in elucidating the interactions of polyene antibiotics with model membrane lipid bilayers as a means of understanding novel drug/membrane interactions at the molecular level.