Metal-based nanoparticles as carriers of mTHPC drug for effective photodynamic therapy

Photodynamic therapy (PDT) is a promising therapeutic modality for cancer treatment. It considered to be minimallyinvasive and nontoxic. Clinical PDT involves systemic administration of photosensitizer drugs, which accumulate at the tumor area and are light sensitive. When laser illuminates the tumor area in the presence of molecular oxygen, highly reactive singlet oxygen is generated, causing to direct killing of the tumor. Despite the advantages of the classical PDT, it suffers from several limitations, impeding its clinical outcome. Thus, developing targeted delivery systems for photosensitizer drugs that will enhance the selectivity is urgently needed. We develop functionalized metal nanoparticles (NPs) as carriers of mTHPC photosensitizer drug. Herein we use NPs composed of either gold or magnetically responsive carries like Ce-doped and Yb-doped-γ-Fe²O³ maghemite NPs (MNPs). All nanocomposites form a stable, soluble compound with improved penetration to cancerous tissues. Gold NPs are effective as contrast agents, and hence the AuNP-mTHPC complex can be used as a biomarker for imaging in vivo. MNPs are superparamagnetic, biocompatible and the resulting hybrid mTHPC-Ce-doped and mTHPC-Yb-doped MNPs can be magnetically attracted to the desired area. We examine all complexes efficiency in MDA-MB231 human breast cancer cells after inducing PDT irradiation for 1 hour and show a high death rate. We demonstrate that magnetic targeting with the use of magnetic based NPs enhance the accumulation of the therapeutic PDT drug in the tumor site. Currently, we develop methods to efficiently and selectively deliver drug complexes in vivo. Our approach is presenting an improved PDT therapy for treating cancer.