Mignet Nathalie, Scherman Daniel
Unité de Pharmacologie Chimique et Génétique, Inserm, U640, Paris, France.
Methods Mol Biol. 2010;605:435-44. doi: 10.1007/978-1-60327-360-2_30.
To provide long circulating nanoparticles which can carry a gene to tumors, we have designed anionic pegylated lipoplexes that are pH sensitive. Anionic pegylated lipoplexes have been prepared from the combined formulation of cationic lipoplexes and pegylated anionic liposomes. The neutralization of the particle surface charge as a function of the pH was monitored by light scattering, in order to determine the ratio between anionic and cationic lipids that would give pH sensitive complexes. This ratio has been optimized to form particles sensitive to pH change in the range 5.5-6.5. Compaction of DNA into these newly formed anionic complexes was checked by DNA accessibility to picogreen. The transfection efficiency and pH sensitive property of these formulations were shown in vitro using bafilomycin, a vacuolar H(+)-ATPase inhibitor.
为了提供能够携带基因至肿瘤部位的长循环纳米颗粒，我们设计了对pH敏感的阴离子聚乙二醇化脂质体复合物。阴离子聚乙二醇化脂质体复合物由阳离子脂质体复合物和聚乙二醇化阴离子脂质体的组合配方制备而成。通过光散射监测颗粒表面电荷随pH的中和情况，以确定能产生pH敏感复合物的阴离子脂质与阳离子脂质的比例。该比例已得到优化，以形成对5.5 - 6.5范围内pH变化敏感的颗粒。通过DNA与Picogreen的可及性检查DNA压缩到这些新形成的阴离子复合物中的情况。使用液泡H(+) - ATP酶抑制剂巴弗洛霉素在体外展示了这些制剂的转染效率和pH敏感特性。
