Lipid-membrane-incorporated hydrophobic photochromic molecules prepared by the exchange method using cyclodextrins.

It was found that the exchange method for the preparation of lipid-membrane-incorporated guest molecules was applicable not only to fullerenes but also to other hydrophobic molecules such as azobenzene and stilbene. The advantages of this method are that the long-term stability of the lipid-membrane-incorporated azobenzene solution and the maximum ratio of [stilbene]/[lipid] were higher than those prepared by the classical method, which we call the 'premixing method'. Photoisomerisations of these photochromic guest molecules in the lipid membranes maintained the morphology of liposomes.