A preliminary comparison of the photosensitizing properties of porphyrins in aqueous solution and liposomal systems.

The preliminary studies reported here show that at least some lipid soluble porphyrins can easily be incorporated into the membranes of liposomes prepared with different phospholipids; such porphyrins do not leach out of the membranes when the liposomes are stored in aqueous media. In this environment, the lipid soluble porphyrins are very effective photodynamic sensitizers for lipophilic substrates in the liposome membrane, for external amino acids and proteins, and for mammalian cells.