Photo-induced flip-flop of amphiphilic membrane markers

摘要

We demonstrate localized photo-induced flip-flop of stilbazolium markers in model lipid bilayer membranes. The flip-flop mechanism and dynamics are determined by combined two-photon excited fluorescence and second harmonic generation microscopy. Upon illumination of labeled membranes with a femtosecond laser beam, two-photon absorption induced photo-isomerization provokes a significant increase in the cis- marker population whose flip-flop rate was determined to be at least a thousand times faster than that for trans- markers.