Nanoparticles for Photodynamic Therapy

Abstract

Despite being a very young research field, nanoparticle-based photodynamic therapy (PDT) has developed explosively as a research field and many researchers currently contribute to its fast advancement. Multifunctional nanoparticles with versatile compositions hold great promise as photosensitizer delivery systems and as complementary components for PDT. They can overcome most of the shortcomings of first- and second-generation PDT reagents. As a drug delivery system, nanoparticles can efficiently transport hydrophobic photosensitizers in vitro and in vivo. They can help the drugs overcome the physiological and biological barriers and improve cell uptake. The important goals of nanoparticle-based PDT systems are to provide a reasonably long circulation time, specific targeting, PDT efficacy and, if possible, excretion or degradation. Another important aspect of nanoparticles in PDT applications is that they can act as the potential photosensitizers, which can generate reactive oxygen species and produce phototoxicity. In this chapter, the various existing approaches using nanoparticles for photodynamic therapy are summarized. The various challenges in this emerging field are also described.