Department of Chemistry, State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, and iChEM , Fudan University , Shanghai 200433 , China.
School of Electronic and Computer Engineering, Shenzhen Graduate School , Peking University , Shenzhen 518055 , China.
ACS Appl Mater Interfaces. 2019 Mar 13;11(10):10356-10363. doi: 10.1021/acsami.8b18721. Epub 2019 Mar 5.
Magnetic mesoporous silica microspheres with core-shell structure and large pores are highly desired in macromolecules delivery and biocatalysis, biospeparation, and adsorption. In this work, a controllable solvent evaporation induced solution-phase interface co-assembly approach was developed to synthesize core-shell structural magnetic mesoporous silica microspheres with ultralarge mesopore size (denoted as LP-MMS). The synthesis was achieved by employing large-molecular-weight amphiphilic block copolymers poly(ethylene oxide)- block-poly(methyl methacrylate) (PEO- b-PMMA) and small surfactant cetyltrimethylammonium bromide as co-templates, which can co-assemble with silica source in tetrahydrofuran/water solutions. The obtained LP-MMS microspheres possess uniform rasberry-like morphology with a diameter of 600 nm, large primary spherical mesopores (ca. 36 nm), large specific surface area (348 m/g), high specific pore volume (0.59 cm/g), and fast magnetic responsivity with high magnetization (15.9 emu/g). The mesopore morphology can be transformed from spherical to cylindrical through introducing a shearing force during the interfacial co-assembly in the synthesis system. The designed LP-MMS microspheres turn out to be good carriers for enzyme (trypsin) immobilization with a high loading capacity of 80 μg/mg and demonstrate excellent biocatalysis efficiency up to 99.1% for protein digestion within 30 min and good recycling stability with negligible decay in digestion efficiency after reuse for five times.
具有核壳结构和大孔的磁性介孔硅微球在大分子输送和生物催化、生物分离和吸附中受到高度关注。在这项工作中，开发了一种可控的溶剂蒸发诱导的溶液相界面共组装方法，用于合成具有超大介孔尺寸的核壳结构磁性介孔硅微球（表示为 LP-MMS）。该合成通过使用高分子量两亲嵌段共聚物聚（环氧乙烷）-嵌段-聚（甲基丙烯酸甲酯）（PEO-b-PMMA）和小的表面活性剂十六烷基三甲基溴化铵作为共模板来实现，它们可以在四氢呋喃/水溶液中与硅源共组装。所得的 LP-MMS 微球具有均匀的覆盆子状形态，直径为 600nm，具有大的初级球形介孔（约 36nm）、大的比表面积（348m/g）、高的比孔体积（0.59cm/g）和快速的磁响应性，具有高的磁化强度（15.9emu/g）。通过在合成体系中的界面共组装过程中引入剪切力，可以将介孔形态从球形转变为圆柱形。设计的 LP-MMS 微球可作为酶（胰蛋白酶）固定化的良好载体，具有高达 80μg/mg 的高负载能力，并表现出优异的生物催化效率，在 30min 内蛋白质消化率达到 99.1%，在重复使用五次后，消化效率几乎没有下降，具有良好的循环稳定性。
