X-ray induced singlet oxygen generation by nanoparticle-photosensitizer conjugates for photodynamic therapy

determination of singlet oxygen quantum yield

Sandhya Clement, Wei Deng, Elizabeth Camilleri, Brian C. Wilson, Ewa M. Goldys*

*Corresponding author for this work

Research output: Contribution to journalArticle

69 Citations (Scopus)
14 Downloads (Pure)

Abstract

Singlet oxygen is a primary cytotoxic agent in photodynamic therapy. We show that CeF3 nanoparticles, pure as well as conjugated through electrostatic interaction with the photosensitizer verteporfin, are able to generate singlet oxygen as a result of UV light and 8 keV X-ray irradiation. The X-ray stimulated singlet oxygen quantum yield was determined to be 0.79 ± 0.05 for the conjugate with 31 verteporfin molecules per CeF3 nanoparticle, the highest conjugation level used. From this result we estimate the singlet oxygen dose generated from CeF3-verteporfin conjugates for a therapeutic dose of 60 Gy of ionizing radiation at energies of 6 MeV and 30 keV to be (1.2 ± 0.7) × 108 and (2.0 ± 0.1) × 109 singlet oxygen molecules per cell, respectively. These are comparable with cytotoxic doses of 5 × 107-2 × 109 singlet oxygen molecules per cell reported in the literature for photodynamic therapy using light activation. We confirmed that the CeF3-VP conjugates enhanced cell killing with 6 MeV radiation. This work confirms the feasibility of using X- or γ-ray activated nanoparticle-photosensitizer conjugates, either to supplement the radiation treatment of cancer, or as an independent treatment modality.

Original languageEnglish
Article number19954
Pages (from-to)1-9
Number of pages9
JournalScientific Reports
Volume6
DOIs
Publication statusPublished - 28 Jan 2016

Bibliographical note

Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.

Fingerprint Dive into the research topics of 'X-ray induced singlet oxygen generation by nanoparticle-photosensitizer conjugates for photodynamic therapy: determination of singlet oxygen quantum yield'. Together they form a unique fingerprint.

  • Projects

    ARC CoE Nanoscale BioPhotonics (CNBP) (RAAP)

    Piper, J., Goldys, E., Packer, N. & Jin, D.

    20/06/14 → …

    Project: Research

    Cite this