In this study, a triblock copolymer PDMAEMA-b-poly(PEGMA)-b-PDMAEMA (DED) and a diblock copolymer PDMAEMA-b-poly(PEGMA) (DE) were synthesized by atom transfer radical polymerization (ATRP) with the initiators bis(2-bromoisobutyryl) hexanediamide (BiBH) and ethyl 2-bromoisobutyrate (EBiB), respectively. Their molecular weights and chemical compositions were almost the same with only difference being in the block sequences. The influence of the block copolymer structures on the gene transfection results was investigated systematically. Gel retardation assay, atomic force microscopy (AFM) observation, particle size and zeta potential measurements with dynamic light scattering (DLS) were used to characterize the properties of the polymer/pDNA complexes. DED showed moderate aggregation behavior with far less cytotoxicity to in vitro and in vivo to zebrafish than DE, which indicates that DED would be a promising vector for gene therapeutic applications.
本研究分别以双(2-
溴异丁酰)
己二胺(BiBH)和 2-
溴异丁酸乙酯(EBiB)为
引发剂,通过原子转移自由基聚合(ATRP)合成了三嵌段共聚物 PD
MAEMA-b-poly(PE
GMA)-b-PD
MAEMA (DED)和二嵌段共聚物 PD
MAEMA-b-poly(PE
GMA) (DE)。它们的分子量和
化学成分几乎相同,唯一不同的是嵌段序列。我们系统地研究了嵌段共聚物结构对
基因转染结果的影响。凝胶延缓试验、原子力显微镜(A
FM)观察、粒度和 zeta 电位测量以及动态光散射(DLS)被用来表征聚合物/pDNA 复合物的特性。DED 显示出适度的聚集行为,对体外和体内斑马鱼的细胞毒性远低于 DE,这表明 DED 将是一种很有前景的
基因治疗应用载体。