Department of Chemistry, Institute of Biomedical Sciences, Fudan University, Shanghai, China.
Small. 2012 Sep 10;8(17):2715-20. doi: 10.1002/smll.201200217. Epub 2012 Jun 4.
Mesoporous carbon nanospheres (MCNs) with small diameters of ≈90 nm are developed as an efficient transmembrane delivery vehicle of an anticancer drug, doxorubicin (DOX). MCNs exhibit a high loading capacity toward DOX due to hydrophobic interactions and the supramolecular π stacking between DOX and the carbonaceous structures, on which the pH-dependent drug release are successfully achieved. Specifically, DOX can be loaded onto MCNs in basic solution and in a physiological pH range, while release occurs in acidic solution in its ionized state. By effective passive and active targeting, MCNs can be readily internalized into HeLa cells, where the carried DOX can be efficiently released in the acidic microenvironment of the tumors for further therapy. The endocytosis and cytotoxicity of DOX@MCNs toward HeLa cells are investigated by confocal microscopy and MTT assay. This smart pH-dependent drug loading and release property of DOX@MCNs makes it possible to reduce the cytotoxicity to normal tissues during circulation in the body since the normal physiological pH is ≈7.4.
介孔碳纳米球（MCNs）的直径约为 90nm，可作为一种有效的抗癌药物阿霉素（DOX）的跨膜输送载体。MCNs 由于疏水相互作用和 DOX 与碳质结构之间的超分子π堆积作用，对 DOX 具有高的负载能力，在此基础上成功实现了 pH 依赖性药物释放。具体来说，DOX 可以在碱性溶液中和生理 pH 值范围内加载到 MCNs 上，而在酸性溶液中以离子形式释放。通过有效的被动和主动靶向，MCNs 可以很容易地被内吞到 HeLa 细胞中，其中携带的 DOX 可以在肿瘤的酸性微环境中有效地释放出来，以进行进一步的治疗。通过共聚焦显微镜和 MTT 测定研究了 DOX@MCNs 对 HeLa 细胞的内吞作用和细胞毒性。DOX@MCNs 的这种智能 pH 依赖性药物加载和释放特性使得在体内循环过程中降低对正常组织的细胞毒性成为可能，因为正常的生理 pH 值约为 7.4。
