Preparation, microstructure and function of liposome with light responsive switch

A novel liposome with photo-responsiveness was prepared by a combined method of thin film hydration and supercritical carbon dioxide technique. In liposomes, curcumin and 4-butylazobenzene-4-hexyloxy-trimethyl-ammo-niumtrifluoro-acetate (BHA) were used as model drug and photo-responsive reversible switch, respectively. Optimum incubation temperature of drug was determined by using phase transition temperature of the liposomes. Morphology and size of liposomes were obtained by transmission electron microscope and dynamic light scattering technology. Microstructure of liposomes was explored by fluorescent probes, and it was found that the BHA was encapsulated in polar groups of phospholipid in the bilayer of liposomes. Light responsiveness and reversibility of BHA in liposomes were studied from the viewpoint of the microstructure and the macro property. It was shown that the reversibility of structural isomerization of BHA can be used as photo-responsive switch to control drug release.