Key Laboratory of Biomedical Polymers of Ministry of Education, Department of Chemistry, Wuhan University, Wuhan, PR China.
J Microencapsul. 2010;27(4):345-54. doi: 10.3109/02652040903215963.
A convenient and effective 'ultrasonic dispersion method' was used to fabricate vector/DNA complexes encapsulated microspheres. Polyamidoamine (PAMAM) dendrimer/DNA complexes protected by a water-soluble polymer, poly-alpha,beta-[N-(2-hydroxyethyl)-L-aspartamide] (PHEA), were encapsulated in a polymer film mainly composed of cholic acid functionalized star poly(DL-lactide), which degraded through surface erosion mechanism with a fast degradation rate. The PAMAM/DNA complexes encapsulated polymer film was then immersed in ethanol and ultrasonicated to afford the microspheres. The in vitro gene transfections showed PAMAM/DNA complexes protected by PHEA exhibited a much higher transfection activity compared with PAMAM/DNA complexes without the protection by PHEA. The expressions of pGL3-Luc in HEK293 cells could be effectively mediated by the polymer film and microspheres with the presence of PHEA. The ultrasonic dispersion method, which did not involve toxic organic solvents, could keep the bioactivity of DNA and offer good control over the size of microspheres.
一种方便有效的“超声分散法”被用于制备包裹有载体/DNA 复合物的微球。聚酰胺-胺（PAMAM）树枝状大分子/DNA 复合物被一种水溶性聚合物，聚-α，β-[N-（2-羟乙基）-L-天冬酰胺]（PHEA）保护，包裹在主要由胆酸功能化星型聚（DL-丙交酯）组成的聚合物薄膜中，该聚合物薄膜通过表面侵蚀机制快速降解。然后将 PAMAM/DNA 复合物包裹的聚合物薄膜浸入乙醇中并进行超声处理，得到微球。体外基因转染实验表明，与未被 PHEA 保护的 PAMAM/DNA 复合物相比，被 PHEA 保护的 PAMAM/DNA 复合物具有更高的转染活性。在存在 PHEA 的情况下，聚合物薄膜和微球可以有效地介导 pGL3-Luc 在 HEK293 细胞中的表达。超声分散法不涉及有毒有机溶剂，可保持 DNA 的生物活性，并能很好地控制微球的粒径。
