Theranostic Nanoconjugates of Tetrapyrrolic Macrocycles and Their Applications in Photodynamic Therapy

Abstract

Members of the tetrapyrrolic macrocycle family possess a unique property of singlet oxygen generation upon exposure to light, which can destroy cancer cells as well as remove infection. Photodynamic therapy (PDT) is an excellent treatment paradigm for cancer and microbial infection. PDT requires light, a photosensitizer (e.g. a tetrapyrrolic macrocycle) and singlet oxygen, and most importantly PDT leaves minimal side effects to the surrounding tissues. Tetrapyrrolic macrocycles, though useful as photosenstizers, their inherent hydrophobicity prevents major applications in biology. Nowadays, nanotherapeutics are frequently used to play essential roles in the treatment of many fatal diseases. Nanomaterials can combine therapeutic, diagnostic and targeting agents in the same scaffold and work efficiently in biological systems due to their well-defined hydrophilic properties. When photosensitizers are combined with nanscaffolds, the combination can make PDT highly effective both in vitro and in vivo. This book chapter describes about tetrapyrrolic photosensitizer nanoconjugates and their applications in photodynamic therapy (PDT).