Melanin Nanoparticle - Infrared Light Cancer Therapy

Abstract

Photothermal therapy (PTT) uses light to target cancer by local heating of a light-absorbing medium proximate to or internalized by cells and malignant tumors. It uses a photosensitizer molecule that, upon absorption of light, locally heats up that attack cancer cells in their environs, leading to hyperthermia  and initiating apoptosis. Clinically, PTT uses light in the UV to visible range but, due to strong absorbance by blood and tissue, can only address cancer in parts of the body the light can reach, such as skin, eyes, mouth, and esophagus. A number of current technical difficulties can be overcome by incorporating of strongly infrared-absorbing melanin nanoparticles (mNP), which are biologically benign and strongly optically absorbing in the visible and IR regions. A collaboration between Michael Naughton in Physics, Kris Kempa in Physics and Tom Seyfried in Biology is using mNPs in a PTT targeting three cell lines known to exhibit strong macrophagic character. The project will use NIR light, which both penetrates deeper than visible and is absorbed more strongly in melanin compared to competing matter such as blood and tissue. Results of this study could lead to the development of a therapy for control of metastatic stages of cancer.