Cavalieri Francesca, Postma Almar, Lee Lillian, Caruso Frank
Centre for Nanoscience and Nanotechnology, Department of Chemical and Biomolecular Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
ACS Nano. 2009 Jan 27;3(1):234-40. doi: 10.1021/nn800705m.
We report the synthesis and characterization of DNA-grafted poly(N-isopropylacrylamide) (PNIPAM) micelles, their assembly into multilayered thin films, and the subsequent generation and poly(ethylene glycol) (PEG) functionalization of DNA-PNIPAM microcapsules. Multilayer films were assembled by sequentially depositing DNA-grafted PNIPAM micelles containing the cDNA sequences polyA(30) or polyT(30) (i.e., PNIPAM-A(30) or PNIPAM-T(30)). DNA-polymer microcapsules were obtained by the alternate deposition of PNIPAM-A(30) and PNIPAM-T(30) onto silica particles, followed by removal of the template core. Upon removal of the silica core particle, shrinkage of between 30 and 50% was observed for the microcapsules. The presence of PNIPAM within the DNA-polymer hybrid film reduces the permeability of the microcapsules to macrosolutes (e.g., dextran) compared with microcapsules made solely of DNA. The hydrophobic core of the DNA-grafted PNIPAM micelles was designed to contain alkyne "click" groups, which were exploited to covalently couple azide-bearing low-fouling PEG to the DNA-PNIPAM microcapsules. The combination of hydrophobic and reactive "click" nanodomains, along with the degradability of DNA, offers a multifunctional and versatile DNA-polymer capsule system that is envisioned to find applications in the controlled delivery of therapeutics.
我们报道了DNA接枝聚（N-异丙基丙烯酰胺）（PNIPAM）胶束的合成与表征、它们组装成多层薄膜以及随后DNA-PNIPAM微胶囊的生成和聚乙二醇（PEG）功能化。多层膜是通过依次沉积含有cDNA序列polyA(30)或polyT(30)（即PNIPAM-A(30)或PNIPAM-T(30)）的DNA接枝PNIPAM胶束组装而成。DNA-聚合物微胶囊是通过将PNIPAM-A(30)和PNIPAM-T(30)交替沉积到二氧化硅颗粒上，然后去除模板核心而获得的。去除二氧化硅核心颗粒后，观察到微胶囊收缩了30%至50%。与仅由DNA制成的微胶囊相比，DNA-聚合物杂化膜中PNIPAM的存在降低了微胶囊对大分子溶质（如葡聚糖）的渗透性。DNA接枝PNIPAM胶束的疏水核心设计为含有炔基“点击”基团，利用该基团将带有叠氮化物的低污染PEG共价偶联到DNA-PNIPAM微胶囊上。疏水和反应性“点击”纳米域的组合，以及DNA的可降解性，提供了一种多功能且通用的DNA-聚合物胶囊系统，预计可用于治疗药物的控制递送。
