Light sensitive liposomes

The delivery of therapeutic agents to a specific cellular site is a central challenge in the treatment of different diseases. Liposomes that can release their cargo upon an externally controlled trigger, such as light, are attractive candidates for localized drug release. We investigate the potential of light-induced release from liposomes with different encapsulated photosensitizers.

As a test system, we encapsulate calcein in high concentration inside the liposomes, so that the calcein fluorescence is quenched. If calcein is released from the liposome, quenching is avoided and the fluorescence increases. The increase of fluorescence intensity is used to quantify the release.