Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE, United States.
Int J Pharm. 2010 Mar 15;387(1-2):278-85. doi: 10.1016/j.ijpharm.2009.12.024. Epub 2009 Dec 16.
Non-viral polymeric gene delivery systems offer increased protection from nuclease degradation, enhanced plasmid DNA (pDNA) uptake, and controlled dosing to sustain the duration of pDNA action. Such gene delivery systems can be formulated from biocompatible and biodegradable polymers such as poly(D,L-lactic-co-glycolic) acid (PLGA). Experimental loading of hydrophilic macromolecules such as pDNA is low in polymeric particles. The study purpose was to develop a supercritical fluid extraction of emulsions (SFEE) process based on CO(2) for preparing pEGFP-PLGA nanoparticles with high plasmid loading and loading efficiency. Another objective was to determine the efficacy of pFlt23k, an anti-angiogenic pDNA capable of inhibiting vascular endothelial growth factor (VEGF) secretion, following nanoparticle formation using the SFEE process. Results indicated that the SFEE process allows high actual loading of pDNA (19.7%, w/w), high loading efficiency (>98%), and low residual solvents (<50 ppm), due to rapid particle formation from efficient solvent removal provided by the SFEE process. pFlt23K-PLGA nanoparticles were capable of in vitro transfection, significantly reducing secreted VEGF from human lung alveolar epithelial cells (A549) under normoxic and hypoxic conditions. pFlt23K-PLGA nanoparticles did not exhibit cytotoxicity and are of potential value in treating neovascular disorders wherein VEGF levels are elevated.
非病毒聚合物基因传递系统提供了更高的保护，免受核酸酶的降解，增强质粒 DNA（pDNA）的摄取，并控制剂量以维持 pDNA 作用的持续时间。这样的基因传递系统可以由生物相容性和可生物降解的聚合物制成，如聚（D，L-乳酸-共-乙醇酸）（PLGA）。亲水性大分子如 pDNA 的实验加载量在聚合物颗粒中较低。研究目的是开发一种基于 CO2 的超临界流体萃取乳液（SFEE）工艺，用于制备具有高质粒载量和载药效率的 pEGFP-PLGA 纳米粒子。另一个目的是确定 pFlt23k 的功效，pFlt23k 是一种能够抑制血管内皮生长因子（VEGF）分泌的抗血管生成 pDNA，使用 SFEE 工艺形成纳米粒子后。结果表明，SFEE 工艺允许高实际负载 pDNA（19.7%，w/w），高载药效率（>98%）和低残留溶剂（<50ppm），这是由于 SFEE 工艺提供的高效溶剂去除快速形成颗粒。pFlt23K-PLGA 纳米粒子能够在体外转染，在常氧和缺氧条件下显著减少人肺肺泡上皮细胞（A549）分泌的 VEGF。pFlt23K-PLGA 纳米粒子没有表现出细胞毒性，在治疗 VEGF 水平升高的新生血管疾病方面具有潜在价值。
