Dual imaging and photodynamic therapy anticancer theranostic nanoparticles

Abstract Photodynamic therapy (PDT) is a relatively new noninvasive cancer treatment modality that has attracted attention during the past 30 years. PDT is based on the light excitation of a photoactivatable drug (photosensitizer—PS) in the presence of molecular oxygen (3O2) to produce reactive oxygen species, especially singlet oxygen (1O2), responsible for cell death near radiation. For 10 years, thanks to major progress in designing more effective and selective new PSs against cancer cells (i.e., first- to fourth-generation PS), researchers have been combining a PDT and contrast imaging agent in nanoparticle (NP) structures to develop dual imaging and PDT anticancer theranostic NPs. These theranostic NPs enable diagnosis and provide therapy for cancer cells. The main focus of this chapter is to provide an overview of newly developed theranostic NPs and their dual applications in diagnosis and PDT treatment of cancer over the past 10 years.