Related Experiment Video
Updated: Aug 1, 2026

From Fast Fluorescence Imaging to Molecular Diffusion Law on Live Cell Membranes in a Commercial Microscope
Published on: October 9, 2014
The diffusion-concentration product of oxygen in lipid bilayers using the spin-label T1 method
Abstract:
A method is described to measure the oxygen diffusion-concentration product, DO[O2], at any locus that can be probed or labeled using nitroxide radicals. The method is based on the dependence of the spin-lattice relaxation time T1 of the spin label on the bimolecular collision rate with oxygen. Strong Heisenberg exchange between spin label and oxygen contributes directly to T1 of the spin label, while dipolar interactions are negligible. Both time-domain and continuous wave saturation methods for studying T1 are considered. The method has been applied to phospholipid liposomes using fatty acid spin labels. A discontinuity in DO[O2] at the main phase transition was observed.
Related Concept Videos
Diffusion
Protein Diffusion in the Membrane
Diffusion

