Department of Chemistry, Huazhong University of Science and Technology, Wuhan 430074, China.
Biomaterials. 2010 Feb;31(6):1380-91. doi: 10.1016/j.biomaterials.2009.10.056. Epub 2009 Nov 11.
A metal-based nonviral carrier for DNA-transfer in gene therapy was synthesized and characterized. The strong intermolecular pi-pi contacts are common in the observed dinuclear Cu(2+) and Co(2+) complexes of polybenzimidazole ligands. The affinity assays indicated that the strong binding of the complexes to DNA is driven by both electrostatic attractions between the complexes and DNA and the intercalation of the ligands between DNA base pairs. The typical in vitro studies showed that micromolar doses of each complex tested can efficiently and rapidly condense free DNA, either in linear or circular state, from solutions into well defined and globular nanoparticles with varied sizes. Therefore, the formation and dissociation of the DNA condensates were explored in detail under different conditions, indicating that the sizes of DNA condensates can be regulated by changing both doses and incubation time for the different dinuclear complexes. Since the intermolecular pi-pi interactions in the DNA-bound complexes may be a key force to drive DNA condensation, we propose a new DNA condensation model that is essentially distinct from that proposed for the most studied multivalent cationic reagents used in DNA condensation. The cellular uptake experiments successfully performed with the DNA condensates including plasmid pGL3 control vector that strongly expresses luciferase in many types of mammalian cells, as well as cytotoxicity evaluation, demonstrated the potentiality of the dinuclear metal(II) complexes as a new nonviral gene carrier. Finally, the dinuclear Co(2+) complexes of polybenzimidazole ligands are suggested to be the most potential nonviral gene carriers that are not impacted by serum proteins.
一种用于基因治疗中 DNA 转移的基于金属的非病毒载体被合成并进行了表征。在观察到的双核 Cu(2+)和 Co(2+)多苯并咪唑配体配合物中，存在强烈的分子间 π-π 接触。亲和测定表明，配合物与 DNA 的强结合是由配合物与 DNA 之间的静电吸引和配体在 DNA 碱基对之间的嵌入共同驱动的。典型的体外研究表明，测试的每个配合物的毫摩尔剂量都可以有效地、快速地将游离 DNA 从溶液中凝聚成具有不同大小的定义良好的球状纳米颗粒，无论是线性还是环形。因此，在不同条件下详细研究了 DNA 凝聚物的形成和解离，表明通过改变不同双核配合物的剂量和孵育时间，可以调节 DNA 凝聚物的大小。由于 DNA 结合配合物中的分子间 π-π 相互作用可能是驱动 DNA 凝聚的关键力，我们提出了一种新的 DNA 凝聚模型，该模型与用于 DNA 凝聚的研究最多的多价阳离子试剂提出的模型本质上不同。成功地用包括强表达荧光素酶的质粒 pGL3 对照载体在内的 DNA 凝聚物进行了细胞摄取实验，以及细胞毒性评估，证明了双核金属(II)配合物作为新型非病毒基因载体的潜力。最后，建议双核 Co(2+)多苯并咪唑配体配合物是最有潜力的非病毒基因载体，不受血清蛋白的影响。
