Epanchintseva Anna V, Poletaeva Julia E, Pyshnyi Dmitrii V, Ryabchikova Elena I, Pyshnaya Inna A
Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of Russian Academy of Science, Lavrent'ev av., 8, Novosibirsk, 630090, Russian Federation.
Beilstein J Nanotechnol. 2019 Dec 23;10:2568-2578. doi: 10.3762/bjnano.10.248. eCollection 2019.
Gold nanoparticles (AuNPs) are a platform for the creation of nanoconstructions that can have a variety of functions, including the delivery of therapeutic nucleic acids. We previously designed a AuNP/small interfering RNA (siRNA) nanoconstruction consisting of siRNA noncovalently bound on the AuNP surface and showed that this construction, when coated with a lipid shell, was an efficient vehicle for the delivery of siRNA into cells. The goal of the present work was to study the possibility of scaling up the synthesis of AuNP-siRNA and its long-term storage without loss of physicochemical characteristics and siRNA duplex integrity as well as siRNA surface density. Dynamic light scattering, transmission electron microscopy, UV-vis spectroscopy, and electrophoresis were used to study the effect of scaling up the AuNP-siRNA synthesis and long term storage of its suspension on physicochemical properties of the samples and integrity of the siRNA duplex. It was shown that a ten-fold increase in the volume of the reaction mixture decreased the surface density of siRNA by about 10%, which influenced the corresponding physicochemical characteristics of the AuNP-siRNA suspension. The storage of the AuNP-siRNA suspension at 4 °C for different times resulted in the formation of particle clusters of high colloidal stability as demonstrated by conventional methods. These clusters completely disintegrated when albumin was added, indicating that they are agglomerates (and not aggregates) of AuNP-siRNA. The AuNPs-siRNA nanoconstruction demonstrated integrity of the siRNA duplex and high stability of the siRNA surface density during storage for seven months at 4 °C. Thus, it can be concluded that it is possible to scale-up the synthesis of noncovalent AuNP-siRNA and to obtain a nanoconstruction possessing high stability in terms of physicochemical characteristics and siRNA surface density for a long period.
金纳米颗粒（AuNPs）是一种用于构建具有多种功能的纳米结构的平台，这些功能包括治疗性核酸的递送。我们之前设计了一种由非共价结合在AuNP表面的小干扰RNA（siRNA）组成的AuNP/小干扰RNA（siRNA）纳米结构，并表明这种结构在包被脂质外壳后，是一种将siRNA高效递送至细胞的载体。本研究的目的是探讨扩大AuNP-siRNA合成规模并进行长期储存而不损失其物理化学特性、siRNA双链完整性以及siRNA表面密度的可能性。采用动态光散射、透射电子显微镜、紫外可见光谱和电泳等方法，研究扩大AuNP-siRNA合成规模及其悬浮液长期储存对样品物理化学性质和siRNA双链完整性的影响。结果表明，反应混合物体积增加10倍会使siRNA的表面密度降低约10%，这影响了AuNP-siRNA悬浮液相应的物理化学特性。常规方法表明，AuNP-siRNA悬浮液在4℃下储存不同时间会形成具有高胶体稳定性的颗粒聚集体。加入白蛋白后，这些聚集体会完全解体，表明它们是AuNP-siRNA的团聚物（而非聚集体）。AuNPs-siRNA纳米结构在4℃下储存七个月期间，siRNA双链保持完整，siRNA表面密度具有高稳定性。因此，可以得出结论，扩大非共价AuNP-siRNA的合成规模并获得在物理化学特性和siRNA表面密度方面长期具有高稳定性的纳米结构是可行的。
