Characterization of the distribution of spin-lattice relaxation rates of lipid spin labels in fiber cell plasma membranes of eye lenses with a stretched-exponential function.

ABSTRACT: The stretched exponential function (SEF) was used to analyze and interpret saturation recovery (SR) electron paramagnetic resonance (EPR) data obtained from spin-labeled porcine eye-lens membranes. This function has two fitting parameters: the characteristic spin-lattice relaxation rate (T 1str -1) and the stretching parameter (β), which ranges between zero and one. When β = 1, the function is a single exponential. It is assumed that the SEF arises from a distribution of single exponential functions, each described by a T 1 value. Because T 1 -1s are determined primarily by the rotational diffusion of spin labels, they are a measure of membrane fluidity. Since β describes the distribution of T 1 -1s, it can be interpreted as a measure of membrane heterogeneity. The SEF was used to analyze

SUBMITTER: Stein N 

PROVIDER: S-EPMC6594395 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature