Development of Wireless Power-Transmission-Based Photodynamic Therapy for the Induction of Cell Death in Cancer Cells by Cyclometalated Iridium(III) Complexes

Abstract

Photodynamic therapy (PDT), a noninvasive method for cancer therapy, involves the generation of reactive oxygen species (ROS) by the photochemical excitation of photosensitizers (PSs) to induce cell death in cancer cells. A variety of PS including porphyrin derivatives and metal complexes such as iridium (Ir) complexes have been reported. In clinical trials, red-near infrared (NIR) light (650–900 nm) is preferred for the excitation of PSs due to its deeper penetration into tissues compared with visible light (400–500 nm). To overcome this limitation, we established a PDT system that uses cyclometalated iridium(III) (Ir(III)) complexes that are excited with blue light in the wireless power transmission (WPT) system. To achieve this, we developed a light-emitting diode (LED) light device equipped with a receiver coil that receives electricity from the transmitter coil through magnetic resonance coupling. The LEDs in the receiving device use blue light (470 nm) to irradiate a given Ir(III) complex and excite triplet oxygen (3O2) to singlet oxygen (1O2) which induces cell death in HeLa S3 cells (human cervical carcinoma cells). The results obtained in this study suggest that WPT-based PDT represents a potentially new method for the treatment of tumors by a non-battery LED, which are otherwise difficult to treat by previous PDT systems.

Cancer Metabolism: The Role of ROS in DNA Damage and Induction of Apoptosis in Cancer Cells

“…PDT is a new type of anticancer therapy in which ROS generated during treatment induces cell death through oxidative damage to cells (such as mitochondria, DNA, proteins, and cell membranes). Existing research studies show that PDT has a good effect on the treatment of cervical cancer, colon cancer, skin cancer, and lung cancer and that it has fewer adverse effects than surgery, chemotherapy, and radiation treatment [ 141 , 142 ]. PDT is a photochemical reaction.…”

Panchromatic Light-Absorbing [70]Fullerene-Perylene-BODIPY Triad with Cascade of Energy Transfer as an Efficient Singlet Oxygen Sensitizer

“…For the wide application of singlet oxygen in the areas of photodynamic therapy (PDT) [1][2][3][4], in vivo oxygen sensing [5], bioimaging [3] and photocatalysis [6,7], researchers have been exploring ways to produce high yields of singlet oxygen in recent years. Singlet oxygen could be generated by photosensitizers (PSs) upon light irradiation in the presence of molecular oxygen.…”

Cyclometalated C^N diphosphine ruthenium catalysts for Oppenauer-type oxidation/transfer hydrogenation reactions and cytotoxic activity

“…The enhanced basicity at the metal center, combined with the chelate effect that allow increase in the stability of complexes, lead to derivatives that can find applications in several areas, including catalysis, [1][2][3][4][5][6][7] photochemistry, [8][9][10][11] and medicine. 12,13 Particular attention has been devoted to palladium, platinum, rhodium, iridium and ruthenium complexes for the selective functionalization of C-H bonds, via cyclometalation promoted by neighbouring functional groups, 14,15 and for the generation of fine-tuned catalysts for C-C and C-H forming reactions. Thus, cyclometalated ruthenium catalysts have been found active in C-H activation and functionalization, olefin metathesis, transfer hydrogenation (TH), cyclopropanation and cyclization reactions.…”