Fullerenes and fullerene–dye structures in photodynamic therapy

The design of new effective photosensitizers for photodynamic therapy (PDT) is a challenging task since they have to meet a long list of requirements. From this point of view, fullerenes are very attractive since they met almost all requirements of PDT: low toxicity and high reactive oxygen species quantum yield. Fullerenes could be modified with hydrophilic addends, which allow them to achieve excellent amphiphilic properties, the high selectivity of accumulation in tumors, and an acceptable elimination rate from the body. Fullerenes have only one disadvantage—they do not have absorbance in the red and near-infrared spectral regions, which are most suitable for PDT. In this chapter, we have discussed the most promising, in our opinion, way to solve this problem—the creation of fullerene–dye structures. We highlighted the theoretical background and properties of published fullerene–dye structures that could be applied in PDT and summarized it into several tips. We hope that our recommendations will be useful for future researchers who are looking for new effective photosensitizers.