Related Experiment Video
Updated: Aug 14, 2026

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Effects of potassium bromide disk formation on the infrared spectra of dried model proteins
Jeffrey D Meyer1, Mark C Manning, John F Carpenter
1Center for Pharmaceutical Biotechnology, University of Colorado Health Sciences, Denver, Colorado, USA.
Abstract:
The most common method of sample preparation for Fourier transform infrared spectroscopic analysis of proteins in the solid state is compression after mixing with potassium bromide (KBr). Recently, questions have arisen as to whether proteins are conformationally altered by this process. In this study, the amide I Fourier transform infrared spectra of two model proteins, lysozyme and alpha-chymotrypsinogen, were measured before and after compression in KBr, and the effects of moisture exposure and the ratio of KBr to protein were examined. Contrary to earlier reports, compaction of the KBr/protein mixtures did not foster aggregation, and only minor apparent structural alterations were observed.
Related Concept Videos
Infrared (IR) Spectroscopy: Overview
Different compounds display unique properties due to their...
IR Spectrum
Transmittance is defined as the ratio of the radiant power passing through a sample to that from the radiation's source. Multiplying the transmittance by 100 gives the percent transmittance (%T), which varies between 100% (no absorption) and 0% (complete...
IR Spectrum Peak Intensity: Amount of IR-Active Bonds
IR Spectrum Peak Broadening: Hydrogen Bonding
However, the extent of hydrogen bonding influences the observed stretching frequency and band broadening. Intermolecular or intramolecular hydrogen bonding...
IR and UV–Vis Spectroscopy of Aldehydes and Ketones
IR Frequency Region: Fingerprint Region
The...

