Related Experiment Video
Updated: May 6, 2026

Neutron Spin Echo Spectroscopy as a Unique Probe for Lipid Membrane Dynamics and Membrane-Protein Interactions
Published on: May 27, 2021
Spectral inhomogeneity and wavelength-dependent rotation of probe molecules in membranes
1B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 220072, Minsk, Belarus.
Abstract:
Using subnanosecond laser spectrofluorometry, the spectral and polarization time-resolved characteristics of 1-phenylnaphthylamine (1-AN) fluorescent probe in phospholipid bilayer and red blood cell (RBC) membranes have been studied. It is shown that the electronic spectra of the probe in model-membranes are inhomogeneously broadened. In contrast to low-molecular weight solvents, there are two reasons for inhomogeneous broadening. The first is connected with different levels of location of probe molecules in the membrane. Inhomogeneous broadening due to the first factor has a static character. The second reason is similar to that of solutions and linked with fluctuations of solvate structure. This type of broadening has a dynamic character. The process of intermolecular relaxation in membranes is accompanied by the release of the free energy excess, which results in wavelength-dependent rotation of probe.
Related Concept Videos
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
NMR Spectrometers: Resolution and Error Correction
Protein Diffusion in the Membrane
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
¹H NMR Chemical Shift Equivalence: Enantiotopic and Diastereotopic Protons
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...

