Department of Chemical Engineering, ‡Department of Biomedical Engineering, and §College of Pharmacy, The University of Texas at Austin , Austin, Texas 78712, United States.
ACS Nano. 2014 Mar 25;8(3):2908-17. doi: 10.1021/nn500101c. Epub 2014 Feb 24.
In this work, we develop and evaluate polycationic nanoparticles for the delivery of small interfering RNA (siRNA). Delivery remains a major challenge for translating siRNA to the clinic, and overcoming the delivery challenge requires effective siRNA delivery vehicles that meet the demands of the specific delivery strategy. Cross-linked polycationic nanoparticle formulations were synthesized using ARGET ATRP or UV-initiated polymerization. The one-step, one-pot, surfactant-stabilized monomer-in-water synthesis technique may provide a simpler and faster alternative to complicated, multistep techniques and an alternative to methods that rely on toxic organic solvents. The polymer nanoparticles were synthesized using the cationic monomer 2-(diethylamino)ethyl methacrylate, the hydrophobic monomer tert-butyl methacrylate to tune pH responsiveness, the hydrophilic monomer poly(ethylene glycol) methyl ether methacrylate to improve biocompatibility, and cross-linking agent tetraethylene glycol dimethacrylate to enhance colloidal stability. Four formulations were evaluated for their suitability as siRNA delivery vehicles in vitro with the human embryonic kidney cell line HEK293T or the murine macrophage cell line RAW264.7. The polycationic nanoparticles demonstrated efficient and rapid loading of the anionic siRNA following complexation. Confocal microscopy as well as flow cytometry analysis of cells treated with polycationic nanoparticles loaded with fluorescently labeled siRNA demonstrated that the polycationic nanoparticles promoted cellular uptake of fluorescently labeled siRNA. Knockdown experiments using polycationic nanoparticles to deliver siRNA demonstrated evidence of knockdown, thus demonstrating potential as an alternative route to creating polycationic nanoparticles.
在这项工作中，我们开发并评估了用于递送小干扰 RNA (siRNA) 的阳离子纳米颗粒。递送仍然是将 siRNA 转化为临床应用的主要挑战，克服递送挑战需要有效的 siRNA 递送载体，以满足特定递送策略的需求。使用ARGET ATRP 或 UV 引发聚合合成交联阳离子纳米颗粒制剂。一步一锅、表面活性剂稳定的单体在水中的合成技术可能为复杂的多步技术提供一种更简单、更快的替代方法，也为依赖有毒有机溶剂的方法提供一种替代方法。使用阳离子单体 2-(二乙基氨基)乙基甲基丙烯酸酯、疏水性单体叔丁基甲基丙烯酸酯来调节 pH 响应性、亲水性单体聚乙二醇甲基醚甲基丙烯酸酯来提高生物相容性、以及交联剂四乙二醇二甲基丙烯酸酯来增强胶体稳定性，合成了聚合物纳米颗粒。使用人胚肾细胞系 HEK293T 或鼠巨噬细胞系 RAW264.7，体外评估了四种制剂作为 siRNA 递送载体的适用性。阳离子纳米颗粒在复合物形成后能够高效快速地负载阴离子 siRNA。用荧光标记的 siRNA 负载的阳离子纳米颗粒处理细胞的共焦显微镜和流式细胞术分析表明，阳离子纳米颗粒促进了荧光标记的 siRNA 的细胞摄取。用阳离子纳米颗粒递送 siRNA 的敲低实验证明了敲低的证据，因此证明了作为替代途径来制备阳离子纳米颗粒的潜力。
