We report the complexation of poly(ethylene glycol) conjugated double-stranded oligoDNA (PEG-(ds)oligoDNA) with imidazolium-based ionic liquids (ILs) to form polyelectrolyte complex aggregates (PCAs). The PEG-(ds)oligoDNA conjugates are prepared following a solution-phase coupling reaction. The binding of PEG-(ds)oligoDNA with either 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF₄]) or 1-hexyl-3-methylimidazolium tetrafluoroborate ([HMIM][BF₄]) is confirmed by a fluorescence displacement assay. Both ILs show stronger binding affinity to PEG-(ds)oligoDNA than bare (ds)oligoDNA due to the PEG-assisted increase in IL cation concentration in the vicinity of (ds)oligoDNA. The complex morphology formed at various amine (N) to phosphate (P) ratios is also examined. At high N/P ratios above 4, nanosized PCAs are formed, driven by a counterion-mediated attraction among the IL-bound (ds)oligoDNA segments and stabilized by the conjugated PEG segments. The PCAs exhibit near-neutral surface charges and resistance to DNase degradation, suggesting their potential use in gene delivery applications.

中文翻译：

---

聚(乙二醇)-(ds)OligoDNA 缀合物与离子液体的络合


我们报道了聚（乙二醇）共轭双链寡DNA（PEG-（ds）oligoDNA）与咪唑基离子液体（IL）络合形成聚电解质复合物聚集体（PCA）。 PEG-(ds)oligoDNA 缀合物是在溶液相偶联反应后制备的。 PEG-(ds)oligoDNA 与四氟硼酸 1-丁基-3-甲基咪唑鎓 ([BMIM][BF ₄ ]) 或四氟硼酸 1-己基-3-甲基咪唑鎓 ([HMIM][BF < b1>])通过荧光位移测定来证实。由于 PEG 辅助增加了 (ds)oligoDNA 附近的 IL 阳离子浓度，因此两种 IL 均比裸露的 (ds)oligoDNA 表现出更强的对 PEG-(ds)oligoDNA 的结合亲和力。还检查了在各种胺 (N) 与磷酸盐 (P) 比例下形成的复杂形态。在高于 4 的高 N/P 比率下，在 IL 结合的 (ds)oligoDNA 片段之间反离子介导的吸引力驱动下，形成纳米级 PCA，并通过缀合的 PEG 片段稳定。 PCA 表现出接近中性的表面电荷和对 DNase 降解的抵抗力，表明它们在基因传递应用中的潜在用途。