ABSTRACT
The development of porphyrins conjugated to phospholipid side chains has opened new possibilities for novel techniques in medical imaging and therapy applications. Porphyrin-phospholipids (PoP) can self-assemble into nanovesicles such as liposomes or porphysomes which have intrinsic utility in theranostics. PoPs are composed of a phospholipid backbone and single side-chain, along with a single esterified porphyrin group. Porphyrins are macrocyclic organic molecules composed of four linked pyrrole subunits. Photodynamic Therapy (PDT) is attractive as a clinical therapy as it is a minimally invasive repeatable treatment that preserves the biological function of the treated tissues. The photodynamic reaction is initiated when a molecule of photosensitizer absorbs light. The photosensitizer’s electrons are excited from the ground state to a long-lived triplet state. While the role of oxygen in the photochemical reactions of PDT is known, the importance of tumor oxygenation to PDT effectiveness is under investigation. With the development of inorganic nanoparticles came the development of photothermal therapy.
