Undistorted structural analysis of soluble proteins by attenuated total reflectance infrared spectroscopy.

ABSTRACT: Water from the solvent very strongly absorbs light in the frequency range of interest for studying protein structure by infrared (IR) spectroscopy. This renders handling of the observation cells painstaking and time consuming, and limits the reproducibility of the measurements when IR spectroscopy is applied to proteins in aqueous solutions. These difficulties are circumvented by the use of an Attenuated Total Reflectance (ATR) accessory. However, when protein solutions are studied, ATR spectroscopy suffers from several drawbacks, the most severe being nonproportionality of the observed absorbance with the protein concentration and spectral distortions that vary from protein to protein and from sample to sample. In this study, we show (1) that the nonproportionality is due to adsorption of

SUBMITTER: Goldberg ME 

PROVIDER: S-EPMC2253228 | biostudies-literature | 2005 Nov

REPOSITORIES: biostudies-literature