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Updated: Mar 21, 2026

Photodynamic Therapy with Blended Conducting Polymer/Fullerene Nanoparticle Photosensitizers
Published on: October 28, 2015
Artificial pheomelanin nanoparticles and their photo-sensitization properties
Jung Pyo1, Kuk-Youn Ju1, Jin-Kyu Lee1
1Department of Chemistry, Seoul National University, Seoul 151-747, South Korea.
Abstract:
Pheomelanin-type nanoparticles (PMNPs) were synthesized through a simple oxidative polymerization of 3,4-dihydroxyphenylalanine (DOPA) in the presence of cysteine by KMnO4. The synthesized PMNPs had a diameter of approximately 100nm, exhibited high dispersion stability in neutral water and various culture media and possessed similar morphology to naturally occurring pheomelanins. The efficiency of photoinduced generation of hydroxyl radicals from PMNPs was determined and related in vitro cell experiments that were carried out, with data being compared to those from eumelanin-type nanoparticles (EMNPs) and natural sepia melanin nanoparticles. Endocytosed PMNPs showed the highest phototoxicity (~50% viability) to UV-irradiated HeLa cells, confirming the direct relationship between phototoxic efficiency and the generation of hydroxyl radicals through the complex processes of the O2 sensitization.
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