"The overall objective of this proposal is the development of one or more nanosystems loaded with Foscan® and conjugated to cancer cell specific ligands for improving the efficacy and selectivity of photodynamic therapy (PDT) and optimise a fluorescence-based tumour imaging approach. At present, PDT with Foscan® can be very effective but is not selective because Foscan® accumulates in the tumour tissue as well as in healthy ones. A great improvement of the therapy can only come from the availability of a carrier able to seek cancer cells and deliver Foscan® selectively to them. Three types of nanosystems, namely, liposomes, silica nanoparticles or poly(lactide-co-glycolide) copolymer nanoparticles, have been selected as potential nanocarriers for the selective delivery of Foscan®. The selection was mainly based on the different chemical nature of these systems, which can affect biocompatibility. During the first part of the project each type of nanosystem will be optimised through in vitro and in vivo tests and leader nanocarriers will be selected and conjugated to cancer cells specific ligands for increasing the selective delivery of Foscan®. The ligands we will use (folic acid, EGF, and antibodies) for targeting the nanosystems find their corresponding receptor over-expressed on the surface of cancer cells, therefore allowing a selective delivery of drugs in these cells. In vitro and in vivo investigations will be carried to demonstrate the validity of our approach and deliver, at project conclusion, a final product which can then be tested clinically. Because of the red fluorescence emitted by Foscan®, once it is selectively accumulated in cancer cells fluorescence based technique can be used for tumour imaging and diagnosis. Therefore we expect to develop a Foscan® loaded nanosystem/s which can be used for improving both therapeutic and tumour imaging approaches."