Fig. 6: Spin diffusion dynamics in GSCP experiments, highlighting how 1H magnetization propagates from the lipid membrane into the surrounding environment over time.
From: Interface-edited solid-state NMR to study cell interfaces
a Selected GSCP experiments recorded with different spin diffusion times on VSMC samples grown with U-13C-glucose. The spectra show changes in relative 13C intensity as 1H magnetization is transferred out of cell membrane through spin diffusion. In particular, lipid membrane signals decay whereas other signals build up, and before decaying at long spin diffusion times due to 1H spin-lattice relaxation. * labels the position of a carbonyl spinning sideband (b) Plot of the build-up and decay of the integrated 13C signal intensity of lipids and sugars with increasing spin diffusion time. A biexponential fit is displayed to help with the visualization: \(I({t}_{{diff}})={I}_{0}\,\exp (-{t}_{{diff}}/{T}_{{BU}})\times \,(1-\exp (-{t}_{{diff}}/{T}_{1}))\) (c) Length scale of cell membranes and membrane proteins (integrin, pdb code 2vdo). Proton magnetization initially stored in the lipid membrane diffuses through lipid headgroups to the extramembranous domain. Lipid measurements adapted from Nagle et al.31.
