Mechanical and photo-fragmentation processes for nanonization of melanin to improve its efficacy in protecting cells from reactive oxygen species stress

Journal Article · Sat Feb 14 04:00:00 EST 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4907997· OSTI ID:22413110

Liu, Yi-Cheng ^[1]; Chen, Sih-Min ^[2]; Liu, Jhong-Han; Hsu, Hsiang-Wei ^[3]; Lin, Hoang-Yan ^[1]; Chen, Szu-yuan ^[4]

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1. Graduate Institute of Photonics and Optoelectronics, and Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)
2. Graduate Institute of Biophysics, National Central University, Jhongli 32001, Taiwan (China)
3. Department of Physics, National Central University, Jhongli 32001, Taiwan (China)
4. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China)

It has been well established ex vivo that melanin has the ability of scavenging free radicals and reactive oxygen species (ROS), besides other functions. Therefore, we propose to utilize nanonized melanin as medication against acute oxidative stress. For this purpose, we developed and characterized two techniques based on mechanical stir and photo-fragmentation using femtosecond laser pulses, respectively, for disintegration of suspended melanin powder to produce nanometer-sized and water-dispersible melanin. This resolves a major obstacle in the medical and industrial applications of melanin. The viabilities of cultured retinal pigment epithelium (RPE) cells exposed to exogenous H{sub 2}O{sub 2} stress and treated with various conditions of melanin and irradiation were compared. It was found that melanin could be nanonized very effectively with the techniques, and nanonized melanin exhibited a much stronger effect than unprocessed melanin on raising the viability of cultured RPE cells under acute ROS stress. The effect was even more prominent without simultaneous light irradiation, promising for effective in vivo application to the whole body.

• OSTI ID: 22413110
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 6 Vol. 117; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COMPARATIVE EVALUATIONS
EPITHELIUM
HYDROGEN PEROXIDE
IRRADIATION
LASER RADIATION
MELANIN
OXIDATION
OXYGEN
POWDERS
RHODOPSIN
STRESSES
VISIBLE RADIATION
WATER