Photodynamic Therapy using Carbohydrate Conjugated Porphyrins

There has been a long interest and history in using porphyrins for applications in Photodynamic Therapy (PDT) for cancer treatment. These applications arise from their photosensitizing and phototoxic properties. PDT combines a photosensitizer and light to produce highly toxic singlet oxygen and therefore destroy any unwanted cells or tissues. The therapeutic properties of porphyrins and their interactions with different cell organelles and components are dependent on their chemical structures. Research on porphyrins with sugar moieties has been of great interest in the last decade. Glycosylated porphyrins can have greater water solubility than most naturally occurring and synthetic, meso substituted, porphyrins. This property can not only increase the efficacy of drug delivery but also assist the drug elimination from the organism after treatment. The proper lipophilicity of neutral saccharide conjugated porphyrins enable them to permeate better in both lipophilic and hydrophilic biological structures. Furthermore, they can have specific interactions with proteins on cell membranes and thus exhibit specific targeting of cancer cells. Therefore, porphyrins with carbohydrate moieties are very promising candidates for PDT in cancer treatment, and for other therapeutics.