Diol glycidyl ether-bridged cyclens: preparation and their applications in gene delivery
作者:Wen-Jing Yi、Zhi-Hua Feng、Qin-Fang Zhang、Ji Zhang、Ling-Dong Li、Wen Zhu、Xiao-Qi Yu
DOI:10.1039/c0ob00879f
日期:——
Polymeric 1,4,7,10-tetraazacyclododecanes (cyclens) using diol glycidyl ether with different chain length as bridges (5a–e) were designed and synthesized from various diols, 1,7-diprotected cyclen and epichlorohydrin. The molecular weights of the title polymers were measured by GPC with good polydispersity. Agarose gel retardation and fluorescent titration using ethidium bromide showed good DNA-binding ability of 5. They could retard plasmid DNA (pDNA) at an N/P ratio of 4–6 and form polyplexes with sizes around 100–250 nm from an N/P ratio of 10 to 60 and relatively low zeta-potential values (5–22 mV). The cytotoxicity of 5 assayed by MTT is much lower than that of 20 kDa PEI. In vitro transfection against A549 and 293 cells showed that the transfection efficiency (TE) of 5c/DNA polyplexes is close to that of 20 kDa PEI at an N/P ratio of 5. Structure–activity relationship (SAR) of 5 was discussed in their DNA-binding, cytotoxicity, and transfection studies. The TE of 5c/DNA polyplexes could be improved by the introduction of 50 μM of chloroquine, the endosomolytic agents, to pretreated cells. These studies may extend the application areas of macrocyclic polyamines, especially for cyclen.
以不同链长的二醇缩水甘油醚作为桥联基团,设计并合成了系列聚合的 1,4,7,10-四氮杂环十二烷(环定)衍生物(5a–e),其制备方法是以各种二醇、1,7-二保护的环定和环氧氯丙烷为原料。经凝胶渗透色谱(GPC)测定,目标聚合物的分子量分布均匀。通过琼脂糖凝胶电泳和荧光滴定法(用溴化乙锭作为荧光探针)表明 5 具有良好的 DNA 结合能力。其能以较低的 N/P 比值(4–6)抑制质粒 DNA(pDNA)活性,并能在 N/P 比值 10-60 范围内与 pDNA 形成粒径约为 100-250 nm 的聚集体, 且 zeta 电位绝对值(5-22 mV)相对较低。通过 MTT 法测得的 5 的细胞毒性远低于20 kDa 的 PEI。在体外对人肺癌 A549 细胞和人类胚胎肾 293 细胞的转染实验表明,5c/DNA 聚集体的转染效率(TE)与 20 kDa 的 PEI 相近,N/P比值为 5。在 DNA 结合活性、细胞毒性和转染实验过程中探讨了 5 的构效关系。运用溶酶体解离剂氯喹(50 μM)对细胞进行预处理后,能够提高 5c/DNA 聚集体的转染效率。该研究表明,大环聚胺,尤其是环定类化合物将会拥有更广泛的应用领域。