結果與討論：機械式攪拌可以有效奈米化黑色素。在視網膜色素上皮細胞暴露在外源性活性氧壓力下，奈米化黑色素相較於未處理的黑色素明顯有效提高存活率。這個結果在不照光時有更明顯的提升，有希望應用於靜脈給藥的體內試驗。;Aim: It is known that melanin has the ability of scavenging free radicals and reactive oxygen species (ROS). The authors propose to utilize nanonized melanin as medication against endogenous chronic oxidative stress or exogenous acute oxidative stress caused by, e.g., acute radiation exposure.
Materials & Methods: A simple technique based on mechanical stir was developed for nanonization of melanin to produce nanometer-sized and water-dispersible melanin. The viabilities of cultured retinal pigment epithelium (RPE) cells exposed to exogenous H2O2 stress and treated with various conditions of melanin and irradiation were compared.
Results & Conclusion: Melanin can be nanonized very effectively with simple mechanical stir. Nanonized melanin exhibited a much stronger effect than unprocessed melanin on raising the viability of cultured RPE cells under exogenous acute ROS stress. The effect was even more prominent without simultaneous light irradiation, promising for effective in vivo application to the whole body via intravenous administration.