Time-Resolved Fluorescence Anisotropies in Mixed Surfactant Solutions.
Time-resolved fluorescence anisotropy decays of solutions of Triton X-114 (TX-114) with various amounts of sodium dodecyl sulfate (SDS) were measured using the emission both from the surfactant itself and from added perylene. In the former case, the monomer and aggregate species of the surfactant were spectroscopically isolated and were shown to have significantly different rotational correlation times. The rotational diffusion of perylene in micellar TX-114 with small amounts of added SDS appeared to have a component with a very short correlation time. The anisotropy decay curves showed the existence of limiting anisotropies (r(infinity)), indicating hindered probe rotation in the micellar environment. At higher SDS concentrations, the fast-decaying component slowed down and the limiting anisotropy decreased substantially, suggesting some migration of the probe to the interior of the micelle. Copyright 1999 Academic Press.
McCarroll
ME
Environmental and Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, Washington, 99352
Joly
AG
Wang
Z
Friedrich
DM
von Wandruszka R