Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260, USA.
Biomaterials. 2013 Dec;34(37):9688-99. doi: 10.1016/j.biomaterials.2013.08.063. Epub 2013 Sep 10.
Representing a new type of biodegradable cationic block copolymer, well-defined poly(ethylene glycol)-block-cationic polylactides (PEG-b-CPLAs) with tertiary amine-based cationic groups were synthesized by thiol-ene functionalization of an allyl-functionalized diblock precursor. Subsequently the application of PEG-b-CPLAs as biodegradable vectors for the delivery of plasmid DNAs (pDNAs) was investigated. Via the formation of PEG-b-CPLA:pDNA nanocomplexes by spontaneous electrostatic interaction, pDNAs encoding luciferase or enhanced green fluorescent protein were successfully delivered to four physiologically distinct cell lines (including macrophage, fibroblast, epithelial, and stem cell). Formulated nanocomplexes demonstrated high levels of transfection with low levels of cytotoxicity and hemolysis when compared to a positive control. Biophysical characterization of charge densities of nanocomplexes at various polymer:pDNA weight ratios revealed a positive correlation between surface charge and gene delivery. Nanocomplexes with high surface charge densities were utilized in an in vitro serum gene delivery inhibition assay, and effective gene delivery was observed despite high levels of serum. Overall, these results help to elucidate the influence of charge, size, and PEGylation of nanocomplexes upon the delivery of nucleic acids in physiologically relevant conditions.
代表一种新型的可生物降解的阳离子嵌段共聚物，具有叔胺基阳离子基团的精确定义的聚乙二醇嵌段阳离子聚乳酸（PEG-b-CPLA）通过烯丙基功能化的二嵌段前体的硫醇-烯基官能化合成。随后研究了 PEG-b-CPLA 作为可生物降解载体传递质粒 DNA（pDNA）的应用。通过自发静电相互作用形成 PEG-b-CPLA:pDNA 纳米复合物，成功地将编码荧光素酶或增强型绿色荧光蛋白的 pDNA 递送至四种生理上不同的细胞系（包括巨噬细胞、成纤维细胞、上皮细胞和干细胞）。与阳性对照相比，制剂纳米复合物显示出高转染效率和低细胞毒性和溶血水平。在各种聚合物：pDNA 重量比下对纳米复合物的电荷密度进行生物物理特性分析，表明表面电荷与基因传递之间存在正相关。在体外血清基因传递抑制试验中使用具有高表面电荷密度的纳米复合物，尽管存在高水平的血清，但仍观察到有效的基因传递。总体而言，这些结果有助于阐明纳米复合物的电荷、大小和 PEG 化对生理相关条件下核酸传递的影响。
