State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P.R. China.
Chemistry. 2011 Sep 26;17(40):11223-9. doi: 10.1002/chem.201100975. Epub 2011 Aug 18.
Rose bengal-grafted chitosan (RB-CHI), synthesized through dehydration between amino and carboxyl functional groups under mild conditions, was coated onto the outer layer of preformed biodegradable microcapsules consisting of sodium alginate and chitosan. The fabricated photosensitive microcapsules were characterized by optical microscopy, scanning electron microscopy, and confocal laser scanning microscopy. The assembled materials maintained intact spherical morphology and thus showed good ability to form thin films. Electron spin resonance spectroscopy allowed direct observation of the generation of singlet oxygen ((1)O(2)) from photosensitive microcapsules under light excitation at about 545 nm. Furthermore, with increasing light radiation, the content of (1)O(2) increased, as detected by a chemical probe. In vitro cellular toxicity assays showed that RB-CHI-coated photosensitive microcapsules exhibit good biocompatibility in darkness and high cytotoxicity after irradiation, and could provide new photoresponsive drug-delivery vehicles.
玫瑰 Bengal 接枝壳聚糖（RB-CHI）是通过在温和条件下氨基和羧基官能团之间的脱水反应合成的，它被涂覆在由海藻酸钠和壳聚糖组成的预先形成的可生物降解微胶囊的外层上。所制备的光敏感微胶囊通过光学显微镜、扫描电子显微镜和共聚焦激光扫描显微镜进行了表征。组装材料保持完整的球形形态，因此具有良好的形成薄膜的能力。电子顺磁共振波谱允许直接观察到在约 545nm 的光激发下，光敏感微胶囊中（1）O2 的生成。此外，随着光辐射的增加，通过化学探针检测到（1）O2 的含量增加。体外细胞毒性试验表明，RB-CHI 涂层的光敏感微胶囊在黑暗中具有良好的生物相容性，在照射后具有高细胞毒性，可为新的光响应药物输送载体提供了可能性。
