Tarcha Peter J, Pelisek Jaroslav, Merdan Thomas, Waters Jan, Cheung Kent, von Gersdorff Katharina, Culmsee Carsten, Wagner Ernst
Departments of Advanced Drug Delivery, Abbott Laboratories, North Chicago, IL, USA.
Biomaterials. 2007 Sep;28(25):3731-40. doi: 10.1016/j.biomaterials.2007.04.037. Epub 2007 May 3.
Polyethylenimines (PEI) are often inefficient in gene knockdown experiments with small interfering RNA (siRNA), presumably due to the strong complexing properties. A more efficient and potentially degradable oligoethylenimine-based carrier was synthesized by the condensation of 800 molecular weight PEI oligomers with hexanedioldiacrylate. Reaction conditions were chosen such that Michael reaction occurs followed by complete N-acylation of all residual ester bonds resulting in beta-aminopropionamide linkage sites and an average molecular weight of 30,000. Based on NMR analysis, these conditions produced 38% tertiary amides and 62% secondary amides, with about 2% residual carboxylate, presumably from hydrolysis. The ionizable equivalent weight of the carrier increased to 51, compared to a value of 43 for standard PEI. Sensible in vitro knockdown of the luciferase gene in stably transfected HUH7 cells, up to 80% in comparison to non-specific siRNA, demonstrated its suitability for siRNA delivery.
聚乙烯亚胺（PEI）在使用小干扰RNA（siRNA）进行基因敲低实验中往往效率不高，这可能是由于其强大的络合特性。通过将800分子量的PEI低聚物与己二醇二丙烯酸酯缩合，合成了一种更高效且可能可降解的基于低聚乙撑亚胺的载体。选择反应条件以使迈克尔反应发生，随后所有残留酯键完全N-酰化，产生β-氨基丙酰胺连接位点，平均分子量为30,000。基于核磁共振分析，这些条件产生了38%的叔酰胺和62%的仲酰胺，大概有2%的残留羧酸盐，可能来自水解。与标准PEI的43相比，该载体的可电离当量增加到了51。在稳定转染的HUH7细胞中对荧光素酶基因进行了合理的体外敲低，与非特异性siRNA相比高达80%，证明了其适用于siRNA递送。
