Wang Qing, Zhang Chunlei, Shen Guangxia, Liu Huiyang, Fu Hualin, Cui Daxiang
School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.
Institute of Nano Biomedicine and Engineering, Key Laboratory for Thin Film and Microfabrication Technology of the Ministry of Education, Department of Instrument Science & Engineering, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, 800 Dongchuan RD, Shanghai, 200240, China.
J Nanobiotechnology. 2014 Dec 30;12:58. doi: 10.1186/s12951-014-0058-0.
Fluorescent carbon dots (Cdots) have attracted increasing attention due to their potential applications in sensing, catalysis, and biomedicine. Currently, intensive research has been concentrated on the synthesis and imaging-guided therapy of these benign photoluminescent materials. Meanwhile, Cdots have been explored as nonviral vector for nucleic acid or drug delivery by chemical modification on purpose.
We have developed a microwave assisted one-step synthesis of Cdots with citric acid as carbon source and tryptophan (Trp) as both nitrogen source and passivation agent. The Cdots with uniform size show superior water solubility, excellent biocompatibility, and high quantum yield. Afterwards, the PEI (polyethylenimine)-adsorbed Cdots nanoparticles (Cdots@PEI) were applied to deliver Survivin siRNA into human gastric cancer cell line MGC-803. The results have confirmed the nanocarrier exhibited excellent biocompatibility and a significant increase in cellular delivery of siRNA, inducing efficient knockdown for Survivin protein to 6.1%. In addition, PEI@Cdots complexes mediated Survivin silencing, the arrested cell cycle progression in G1 phase as well as cell apoptosis was observed.
The Cdots-based and PEI-adsorbed complexes both as imaging agents and siRNA nanocarriers have been developed for Survivin siRNA delivery. And the results indicate that Cdots-based nanocarriers could be utilized in a broad range of siRNA delivery systems for cancer therapy.
荧光碳点（Cdots）因其在传感、催化和生物医学方面的潜在应用而受到越来越多的关注。目前，大量研究集中在这些良性光致发光材料的合成及成像引导治疗上。同时，人们已通过有意的化学修饰将Cdots探索为用于核酸或药物递送的非病毒载体。
我们开发了一种以柠檬酸为碳源、色氨酸（Trp）作为氮源和钝化剂的微波辅助一步法合成Cdots。尺寸均匀的Cdots表现出优异的水溶性、良好的生物相容性和高量子产率。随后，将聚乙烯亚胺（PEI）吸附的Cdots纳米颗粒（Cdots@PEI）应用于将Survivin小干扰RNA（siRNA）递送至人胃癌细胞系MGC-803。结果证实该纳米载体表现出优异的生物相容性，且siRNA的细胞递送显著增加，使Survivin蛋白有效敲低至6.1%。此外，观察到PEI@Cdots复合物介导Survivin沉默、细胞周期进程阻滞于G1期以及细胞凋亡。
已开发出基于Cdots且吸附了PEI的复合物，其兼具成像剂和siRNA纳米载体的功能，用于递送Survivin siRNA。结果表明基于Cdots的纳米载体可用于广泛的癌症治疗siRNA递送系统。
