MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
Biomaterials. 2011 Nov;32(31):7978-87. doi: 10.1016/j.biomaterials.2011.07.011. Epub 2011 Jul 23.
The functional quantum dots (QDs) were specifically designed to overcome barriers in siRNA delivery such as siRNA protection, cellular penetration, endosomal release, carrier unpacking, intracellular transport and gene silencing. In this paper, two l-arginine-functional-modified CdSe/ZnSe QDs were synthesized as siRNA carriers to silence HPV18 E6 gene in HeLa cells. Using such constructs, these QDs showed significantly low cellular cytotoxicity and good siRNA protection. Flow cytometric and confocal microscopic analyses confirmed that the QDs delivered siRNA into HeLa cells efficiently. Importantly, superior gene silencing efficiency was achieved as evaluated by Reverse Transcription-PCR (RT-PCR) and Western blotting and HeLa cells growth was inhibited in xCELLigence installation analysis and MTT assay when treated with QD-siRNA complexes. Interestingly, the QDs coated with β-CD-l-Arg showed optimized property compared with those coated with l-Arg. Furthermore, these QDs complexes could also be used as nanocrystal probing agents, allowing real-time tracking and localization of QDs during delivery and transfection. The properties and capabilities of these QDs showed that amino acid-modified QDs could be used as useful siRNA carriers to effectively silence a target gene as well as fluorescence probes to analyze intracellular imaging in vivo.
功能化量子点（QDs）专门设计用于克服 siRNA 递送上的障碍，如 siRNA 保护、细胞穿透、内涵体释放、载体解包、细胞内运输和基因沉默。在本文中，我们合成了两种 l-精氨酸修饰的 CdSe/ZnSe QDs 作为 siRNA 载体，以沉默 HeLa 细胞中的 HPV18 E6 基因。使用这些构建体，这些 QDs 表现出显著低的细胞毒性和良好的 siRNA 保护作用。流式细胞术和共聚焦显微镜分析证实 QDs 能够有效地将 siRNA 递送至 HeLa 细胞。重要的是，通过反转录聚合酶链反应（RT-PCR）和 Western blot 评估，我们实现了优异的基因沉默效率，并且在 xCELLigence 安装分析和 MTT 测定中，当用 QD-siRNA 复合物处理时，HeLa 细胞的生长受到抑制。有趣的是，与用 l-Arg 修饰的 QDs 相比，用 β-CD-l-Arg 修饰的 QDs 表现出优化的性质。此外，这些 QDs 复合物还可用作纳米晶体探针剂，允许在递送和转染过程中实时跟踪和定位 QDs。这些 QDs 的性质和功能表明，氨基酸修饰的 QDs 可用作有效的 siRNA 载体，有效地沉默靶基因，并作为荧光探针用于分析体内细胞内成像。
