Nanoparticle based siRNA formulations often suffer from aggregation and loss of function during storage. We in this study report a frozen targeted RGD-polyethylene glycol (PEG)-ECO/siβ3 nanoparticle formulation with a prolonged shelf life and preserved nanoparticle functionality. The targeted RGD-PEG-ECO/siβ3 nanoparticles are formed by step-wised self-assembly of RGD-PEG-maleimide, ECO, and siRNA. The nanoparticles have a diameter of 224.5 ± 9.41 nm and a zeta potential to 45.96 ± 3.67 mV in water and a size of 234.34 ± 3.01 nm and a near neutral zeta potential in saline solution. The addition of sucrose does not affect their size and zeta potential and substantially preserves the integrity and biological activities of frozen and lyophilized formulations of the targeted nanoparticles. The frozen formulation with as low as 5% sucrose retains nanoparticle integrity (90% siRNA encapsulation), size distribution (polydispersity index [PDI] ≤20%), and functionality (at least 75% silencing efficiency) at -80°C for at least 1 year. The frozen RGD-PEG-ECO/siβ3 nanoparticle formulation exhibits excellent biocompatibility, with no adverse effects on hemocompatibility and minimal immunogenicity. As RNAi holds the promise in treating the previously untreatable diseases, the frozen nanoparticle formulation with the low sucrose concentration has the potential to be a delivery platform for clinical translation of RNAi therapeutics.

中文翻译：

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具有长期稳定性的生物相容性靶向 ECO/siRNA 纳米颗粒的配制，用于 RNAi 的临床转化。


基于纳米颗粒的 siRNA 制剂在储存过程中经常会发生聚集和功能丧失。我们在这项研究中报告了一种冷冻靶向 RGD-聚乙二醇 (PEG)-ECO/siβ3 纳米颗粒制剂，具有延长的保质期并保留了纳米颗粒的功能。靶向RGD-PEG-ECO/siβ3纳米颗粒是通过RGD-PEG-马来酰亚胺、ECO和siRNA逐步自组装形成的。纳米粒子的直径为224.5±9.41 nm，在水中的zeta电位为45.96±3.67 mV，在盐溶液中的尺寸为234.34±3.01 nm，zeta电位接近中性。蔗糖的添加不会影响它们的尺寸和zeta电位，并且基本上保留了目标纳米粒子的冷冻和冻干制剂的完整性和生物活性。蔗糖含量低至 5% 的冷冻制剂在 -80°C 下保持纳米颗粒完整性（90% siRNA 封装）、尺寸分布（多分散指数 [PDI] ≤20%）和功能性（至少 75% 沉默效率）。至少1年。冷冻的RGD-PEG-ECO/siβ3纳米颗粒制剂表现出优异的生物相容性，对血液相容性没有不利影响，并且免疫原性极小。由于RNAi有望治疗以前无法治疗的疾病，因此低蔗糖浓度的冷冻纳米颗粒制剂有潜力成为RNAi疗法临床转化的递送平台。