Jinwoo Lee1, Youjin Lee1, Jong Kyu Youn2, Hyon Bin Na1, Taekyung Yu1, Hwan Kim1, Sang Mok Lee3, Yoon‐Mo Koo3, Ja Hun Kwak4, Hyun Gyu Park2, Ho Nam Chang2, Misun Hwang5, Je‐Geun Park5, Jungbae Kim6,4, Taeghwan Hyeon1
1National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea,
2Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea
3Center for Advanced Bioseparation Technology, Inha University, Incheon 402-751, Korea
4Pacific Northwest National Laboratory, Richland, WA 99352, USA
5Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea
6Current address: Department of Chemical and Biological Engineering
Tóm tắt
AbstractUniformly sized silica‐coated magnetic nanoparticles (magnetite@silica) are synthesized in a simple one‐pot process using reverse micelles as nanoreactors. The core diameter of the magnetic nanoparticles is easily controlled by adjusting the w value ([polar solvent]/[surfactant]) in the reverse‐micelle solution, and the thickness of the silica shell is easily controlled by varying the amount of tetraethyl orthosilicate added after the synthesis of the magnetite cores. Several grams of monodisperse magnetite@silica nanoparticles can be synthesized without going through any size‐selection process. When crosslinked enzyme molecules form clusters on the surfaces of the magnetite@silica nanoparticles, the resulting hybrid composites are magnetically separable, highly active, and stable under harsh shaking conditions for more than 15 days. Conversely, covalently attached enzymes on the surface of the magnetite@silica nanoparticles are deactivated under the same conditions.
