Light-induced shape transitions of unilamellar vesicles

In the present study fluorescence microscopy is used in order to investigat e the light-induced shape transitions of giant unilamellar vesicles. Theref ore pyrene was solubilized in the lipophilic core of the bilayer which allo ws the transformation of the shape of unilamellar vesicles upon UV irradiat ion. It turns out that tubular vesicles tend to collapse after illumination forming a string of nearly monodisperse spherical pearls. Giant unilamella r spherical vesicles with small excess areas can be changed reversibly into elliptical aggregates after irradiation with UV light.