EPSRC logo

Details of Grant 

EPSRC Reference: EP/C523830/1
Title: Conjugated Porphyrin Oligomers for Photodynamic Therapy via Two-Photon Absorption
Principal Investigator: Anderson, Professor HL
Other Investigators:
Researcher Co-Investigators:
Project Partners:
Kings College London Montana State University UCL
University of Hull University of Mons
Department: Oxford Chemistry
Organisation: University of Oxford
Scheme: Standard Research (Pre-FEC)
Starts: 03 October 2005 Ends: 02 December 2007 Value (£): 153,016
EPSRC Research Topic Classifications:
Chemical Synthetic Methodology Gas & Solution Phase Reactions
Medical science & disease
EPSRC Industrial Sector Classifications:
Related Grants:
Panel History:  
Summary on Grant Application Form
Photodynamic therapy (PDT) is an established method for treating a variety of cancers (particularly lung, head, neck and non-melanoma skin cancer) and for treating a disease known as acute macular degeneration (AMD), which is the main cause of blindness in people over 50. PDT is carried out by injecting a dye into the patient, then irradiating the sick region of the body with red light. The light energy is absorbed by the dye and transferred to molecular oxygen generating excited singlet oxygen, which kills the surrounding cells. Light consists of particles called photons. Normally dyes absorb just one photon at a time, but at high light intensities, some molecules are able to absorb two photons simultaneously in a process known as 'twophoton absorption' (TPA). The possibility of carrying out PDT by TPA should make this type of therapy more applicable to deeper tumours, and to cases where spatial selectivity is critical, such as brain tumours and abnormal blood vessels in the eye (AMD).Recently we have discovered that a class of dyes known as 'conjugated porphyrin oligomers' give exceptionally strong TPA, and that they can generate singlet oxygen efficiently, and that they exhibit phototoxicity to human breast cancer cells. These three results imply that conjugated porphyrin oligomers should be excellent photosensitisers for two-photon excited PDT. Although it is recognised that two-photon PDT should offer tremendous advantages over conventional one-photon PDT, in terms of greater tissue penetration and better spatial selectivity, the field has been held back by the lack of suitable two-photon photosensitiser dyes. The aim of this project is to explore molecular structure-property relationships for the design of conjugated porphyrin oligomers with high two-photon cross-sections, high singlet-oxygen quantum yields and suitable solubility and cell-binding behaviour for PDT. Our strategy is to use a combination of rational molecular design and fast parallel synthesis with high throughput screening of phototoxicity under both one-photon and two-photon excitation. This is an interdisciplinary project involving molecular design, organic synthesis, photochemistry, photophysics and cell biology.
Key Findings
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Potential use in non-academic contexts
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Description This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Date Materialised
Sectors submitted by the Researcher
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
Project URL:  
Further Information:  
Organisation Website: http://www.ox.ac.uk