Abstract
5(or 8)-sulfonated hypocrellin B (5-SO 3H-HB) is a water-soluble perylenequinone derivative. Electron spin resonance studies in combination with chemical methods show that 5-SO 3H-HB is an active photosensitizer. Visible-light illumination of 5-SO 3H-HB solutions generates a semiquinone radical anion, singlet oxygen, a superoxide radical anion, a hydroxyl radical and hydrogen peroxide. In anaerobic solution, the semiquinone radical anion is predominately photoproduced, via self-electron transfer between the excited and ground states of 5-SO 3H-HB. In aerobic solution, singlet oxygen is generated in the photosensitization of 5-SO 3H-HB. In addition, a superoxide radical anion is also generated from 5-SO 3H-HB on illumination in aerobic solution, via the reduction of oxygen by the semiquinone radical anion. In aqueous solution, the superoxide radical anion formed can rapidly transformed to a hydroxyl radical via the Fenton reaction and via the reaction of the semiquinone radical anion with H 2O 2. Based on these results, the pathways for the photodynamic action of 5-SO 3H-HB have been proposed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Journal of Photochemistry & Photobiology, B: Biology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.