Recent Advances in Developing Photosensitizers for Photodynamic Cancer Therapy

Background & Aim: Photosensitizers are key molecules used in photodynamic cancer therapy (PDT), which is an effective therapeutic modality option for several diseases and non-oncological disorders. Due to its lower systemic toxicity and its ability to destroy tumors selectively, PDT has been considered as clinical avenue for the treatment of several cancers. Methods & Results: Three essential elements are involved in a PDT procedure: a photosensitizer, light of a specific wavelength, and singlet oxygen. However, the properties of conventional photosensitizers exhibit some drawbacks that may limit their use. Nanoparticles can provide significant benefits that counter these drawbacks and enable higher efficiency and biosafety. With the development of nanotechnology, nanoparticles have been used to encapsulate photosensitizers to enhance the phototoxic and pharmacokinetic properties of these agents. Conclusion: Here, the main motivation for this review is to summarize recent progress in the development of photosensitizers, in particular, photosensitizers with nanoparticle modifications. In addition, we reviewed the clinical treatment of several diseases using photosensitizers formulated with nanoparticles, with the overall goal of aiding the design and development of novel photosensitizers.