Gao Fei, Botella Pablo, Corma Avelino, Blesa Jose, Dong Lin
Instituto de Tecnologia Quimica, UPV-CSIC, Avenida Los Naranjos s/n, 46022 Valencia, Spain.
J Phys Chem B. 2009 Feb 12;113(6):1796-804. doi: 10.1021/jp807956r.
Silica nanoparticles with controlled diameter (approximately 70-300 nm) and with uniform pores of 20 nm are prepared by a low temperature (10 degrees C) synthetic method in the presence of a dual surfactant system. While a triblock copolymer (Pluronic F127) acts as supramolecular template and coassembles with hydrolyzed silica species to develop a partially ordered mesophase with face-centered cubic symmetry, a fluorocarbon surfactant with high surface activity (FC-4) surrounds the silica particles through S+X-I+ interactions, thereby limiting their growth. The final textural properties of this material are achieved by means of a subsequent hydrothermal treatment to yield high pore volume mesoporous silica nanoparticles with the largest pore entrance size (17 nm) and cavity diameter (20 nm) reported up to now. After surface modification with aminopropyl groups, the nanoparticles are able to encapsulate inside the pores molecules of the firefly luciferase plasmid DNA (pGL3-Control, 5256 pb), leading to stable conjugates with up to 0.07 microg DNA m(-2), which is the highest content achieved with silica-based materials. Furthermore, plasmid DNA becomes protected from enzymatic degradation when conjugated with the mesostructured nanoparticles.
通过在双表面活性剂体系存在下的低温（10摄氏度）合成方法，制备出直径可控（约70 - 300纳米）且具有20纳米均匀孔隙的二氧化硅纳米颗粒。三嵌段共聚物（普朗尼克F127）作为超分子模板，与水解的二氧化硅物种共组装形成具有面心立方对称性的部分有序中间相，而具有高表面活性的碳氟表面活性剂（FC - 4）通过S + X - I +相互作用围绕二氧化硅颗粒，从而限制其生长。这种材料的最终结构性质是通过随后的水热处理实现的，以产生具有迄今报道的最大孔入口尺寸（17纳米）和腔直径（20纳米）的高孔容介孔二氧化硅纳米颗粒。用氨丙基进行表面改性后，纳米颗粒能够在孔内包封萤火虫荧光素酶质粒DNA（pGL3 - Control，5256 pb）分子，形成稳定的缀合物，DNA含量高达0.07微克/平方米，这是基于二氧化硅材料所达到的最高含量。此外，当与介孔结构纳米颗粒缀合时，质粒DNA受到保护，免受酶促降解。
