State Key Laboratory of Chemical Resource Engineering, Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, College of Materials Science & Engineering, Beijing University of Chemical Technology, Beijing, China.
Bioconjug Chem. 2011 Sep 21;22(9):1842-51. doi: 10.1021/bc200241m. Epub 2011 Aug 26.
Successful gene transfection on a tissue scaffold is of crucial importance in facilitating tissue repair and regeneration by enabling the localized production of therapeutic drugs. Polycaprolactone (PCL) has been widely adopted as a scaffold biomaterial, but its unfavorable cell-adhesion property needs to be improved. In this work, the PCL film surface was conjugated with poly((2-dimethyl amino)ethyl methacrylate) (P(DMAEMA))/gelatin complexes via surface-initiated atom transfer radical polymerization (ATRP) for improving cell immobilization and subsequent gene transfection. A simple aminolysis-based method was first used for the covalent immobilization of ATRP initiators on the PCL film. Well-defined P(DMAEMA) brushes were subsequently prepared via surface-initiated ATRP from the initiator-functionalized PCL surfaces. The P(DMAEMA) chains with a pK(a) of 7.0-7.3 were used for conjugating gelatin with a pI of 4.7 via electrostatic interaction. The amount of complexed gelatin increased as that of the grafted P(DMAEMA) layer. The cell-adhesion property on the functionalized PCL surface could be controlled by adjusting the ratio of P(DMAEMA)/gelatin. It was found that the gene transfection property on the immobilized cells was dependent on the density of the immobilized cells on the functionalized PCL film. With the good cell-adhesive nature of gelatin and the efficient gene transfection on the dense immobilized cells, the incorporating the suitable of P(DMAEMA)/gelatin complexes onto PCL surfaces could endow the PCL substrates new and interesting properties for potential tissue engineering applications.
成功地将基因转染到组织支架上对于促进组织修复和再生至关重要，因为它能够局部产生治疗药物。聚己内酯（PCL）已被广泛用作支架生物材料，但需要改善其不利的细胞粘附性能。在这项工作中，通过表面引发原子转移自由基聚合（ATRP）将聚（（2-二甲氨基）乙基甲基丙烯酸酯）（P（DMAEMA））/明胶复合物接枝到 PCL 薄膜表面，以提高细胞固定化和随后的基因转染效率。首先，使用基于简单氨解的方法将 ATRP 引发剂共价固定在 PCL 薄膜上。随后，通过从引发剂功能化的 PCL 表面引发的表面引发 ATRP，制备了具有明确结构的 P（DMAEMA）刷。具有 pK（a）为 7.0-7.3 的 P（DMAEMA）链用于通过静电相互作用将 pI 为 4.7 的明胶与接枝的 P（DMAEMA）链进行共轭。接枝的 P（DMAEMA）层越多，复合的明胶量就越大。可以通过调整接枝的 P（DMAEMA）/明胶的比例来控制功能化 PCL 表面的细胞粘附性能。发现固定化细胞上的基因转染性能取决于功能化 PCL 薄膜上固定化细胞的密度。由于明胶具有良好的细胞粘附性和对致密固定化细胞的高效基因转染，因此将合适的 P（DMAEMA）/明胶复合物掺入 PCL 表面可以为潜在的组织工程应用赋予 PCL 基底新的有趣的特性。
