Publication Details (including relevant citation information):
E.Okamura, C.Wakai, N.Matubayasi, Y.Sugiura, and M.Nakahara, Phys. Rev. Lett. 93, 248101 (2004).
Self-diffusion rates of lipids and trapped bisphenol A (BPA) are determined in various sizes of confined but fluid membranes by high-field-gradient NMR at 600 MHz. Micelles and vesicles of 3- to 400-nm diameters are used as model membranes, to get an insight into the molecular diffusion in such soft environments. The slowdown of BPA and lipid motions is leveled off in 100- and 400-nm vesicles, although the hydrodynamic (HD) continuum model gives the aggregate motion slowed inversely to the aggregate size. Instead, the limited motion is related to the intra-aggregate fluidity of the membrane.