Presentation
27 April 2016 Towards photodynamic therapy with ionizing radiation: nanoparticle-mediated singlet oxygen generation (Conference Presentation)
Sandhya Clement, Wei Deng, Elizabeth Camilleri, Brian Wilson, Ewa Goldys
Author Affiliations +
Abstract
Photodynamic therapy (PDT) is a clinically approved method for the treatment of cancer by using singlet oxygen, a highly reactive oxygen generated from a photosensitizer drug upon photoactivation. Limited light penetration depth into to the tissue means that PDT is unsuitable for deep tissue cancer treatments. This can be overcome by using X-ray /gamma rays activated nanoparticles able to trigger the photosensitizer drug and generate singlet oxygen. Additionally, inorganic nanoparticles interact more strongly with X and/or gamma rays than the tissue, allowing to concentrate the effects of radiation near nanoparticle surface and they can also be molecularly targeted to cancer cells. In this work we synthesized and characterized CeF3 nanoparticles, a well-known scintillator material. The nanoparticles were conjugated with Verteporfin, a photosensitizer drug by electrostatic interaction. We assessed the performance of CeF3 and the conjugates to generate singlet oxygen exposed to X-ray radiation. The X-ray singlet oxygen quantum yield of the nanoparticle-photosensitizer system was accurately quantified for the first time. This provided realistic estimates of the singlet oxygen dose taking into consideration the dose partition of the radiation between CeF3 and the tissue. Furthermore, we investigated gold nanoparticle-photosensitizer systems. We confirmed that pure gold nanoparticles itself generate singlet oxygen which is attributed to plasmonic effects. We found enhanced singlet oxygen generation from gold-Rose Bengal conjugates and gold nanorod–verteporfin conjugates. These singlet-oxygen-generating nanomaterials add a new dimension to radiation-assisted PDT.
Conference Presentation
© (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Sandhya Clement, Wei Deng, Elizabeth Camilleri, Brian Wilson, and Ewa Goldys "Towards photodynamic therapy with ionizing radiation: nanoparticle-mediated singlet oxygen generation (Conference Presentation)", Proc. SPIE 9722, Colloidal Nanoparticles for Biomedical Applications XI, 972217 (27 April 2016); https://doi.org/10.1117/12.2209206
Advertisement
Advertisement
KEYWORDS
Oxygen

Nanoparticles

Photodynamic therapy

Cancer

Gold

Radiation effects

X-rays

Back to Top