Department of Chemical & Biomolecular Engineering, National University of Singapore, Singapore 117576, Singapore.
Biomaterials. 2012 Apr;33(12):3494-501. doi: 10.1016/j.biomaterials.2012.01.036. Epub 2012 Feb 4.
The aim of this work was to develop a new type of D-alpha-tocopheryl polyethylene glycol 1000 succinate mono-ester (TPGS) coated multi-functional (theranostic) liposomes, which contain both docetaxel and quantum dots (QDs) for cancer imaging and therapy. Non-targeting and folate receptor targeting TPGS coated theranostic liposomes were prepared by the solvent injection method and characterized for their particle size, polydispersity, zeta potential, surface chemistry and drug encapsulation efficiency. MCF-7 breast cancer cells of folate receptor overexpression were employed as an in vitro model to assess cellular uptake and cytotoxicity of the drug and QDs loaded liposomes. The mean particle size of the non-targeting and the targeting liposomes was found to be 202 and 210 nm, respectively. High resolution field emission transmission electron microscopy (FETEM) confirmed the presence of quantum dots in the peripheral hydrophobic membranes of the liposomes. The qualitative internalization of multi-functional liposomes by MCF-7 cells was visualized by confocal laser scanning microscopy (CLSM). The IC50 value, which is the drug concentration needed to kill 50% cells in a designated time period, was found to be 9.54 ± 0.76, 1.56 ± 0.19 and 0.23 ± 0.05 μg/ml for the commercial Taxotere(®), non-targeting and targeting liposomes, respectively after 24 h culture with MCF-7 cells. The targeting multi-functional liposomes showed greater efficacy than the non-targeting liposomes and thus great potential to improve the cancer imaging and therapy.
这项工作的目的是开发一种新型 D-α-生育酚聚乙二醇 1000 琥珀酸单酯(TPGS)包覆的多功能(治疗诊断一体化)脂质体,其既包含多西紫杉醇又包含量子点(QDs),用于癌症成像和治疗。通过溶剂注入法制备了非靶向和叶酸受体靶向 TPGS 包覆的治疗诊断一体化脂质体,并对其粒径、多分散性、Zeta 电位、表面化学和药物包封效率进行了表征。选择叶酸受体过表达的 MCF-7 乳腺癌细胞作为体外模型,评估载药和载 QDs 脂质体的细胞摄取和细胞毒性。非靶向和靶向脂质体的平均粒径分别为 202nm 和 210nm。高分辨率场发射透射电子显微镜(FETEM)证实了量子点存在于脂质体的外周疏水性膜中。通过共聚焦激光扫描显微镜(CLSM)可视化了多功能脂质体的定性内化。24 小时 MCF-7 细胞培养后,商业 Taxotere(®)、非靶向和靶向脂质体的 IC50 值(杀死指定时间内 50%细胞所需的药物浓度)分别为 9.54±0.76μg/ml、1.56±0.19μg/ml 和 0.23±0.05μg/ml。靶向多功能脂质体比非靶向脂质体具有更高的疗效,因此具有改善癌症成像和治疗的巨大潜力。