Solvation Dynamics of DCM in Lipid

Abstract

Solvation dynamics of 4-(dicyanomethylene)-2-methyl-6(p-dimethylaminostyryl)-4H-pyran (DCM) in dimyristoylphosphatidylcholine (DMPC) vesicles in water is studied by using the picosecond time-resolved Stokes shift technique. In unilamellar DMPC vesicles, DCM exhibits wavelength-dependent fluorescence decays with a fast decay at the blue end and a slow decay preceded by a distinct growth at the red end of the emission spectrum. The solvation dynamics of DCM in DMPC vesicles is found to be biexponential with two components 230 ps (40%) and 1.6 ns (60%) and is attributed to the relaxation of the water molecules inside the water pool of DMPC vesicles.