Hierarchical Self-Assembly and Optical Disassembly for Controlled Switching of Magnetoferritin Nanoparticle Magnetism

详细信息    查看全文

• 作者：Mauri A. Kostiainen ; Pierpaolo Ceci ; Manuela Fornara ; Panu Hiekkataipale ; Oksana Kasyutich ; Roeland J. M. Nolte ; Jeroen J. L. M. Cornelissen ; Ryan D. Desautels ; Johan van Lierop
• 刊名：ACS Nano
• 出版年：2011
• 出版时间：August 23, 2011
• 年：2011
• 卷：5
• 期：8
• 页码：6394-6402
• 全文大小：1117K
• 年卷期：0
• ISSN：1936-086X

文摘

Protein cages such as ferritin and viral capsids are interesting building blocks for nanotechnology due to their monodisperse structure and ability to encapsulate various functional moieties. Here we show that recombinant ferritin protein cages encapsulating Fe₃O₄–γ-Fe₂O₃ iron oxide (magnetoferritin) nanoparticles and photodegradable Newkome-type dendrons self-assemble into micrometer-sized complexes with a face-centered-cubic (fcc) superstructure and a lattice constant of 13.1 nm. The magnetic properties of the magnetoferritin particles are affected directly by the hierarchical organization. Magnetoferritin nanoparticles dispersed in water exhibit typical magnetism of single domain noninteracting nanoparticles; however, the same nanoparticles organized into fcc superstructures show clearly the effects of the altered magnetostatic (e.g., dipole–dipole) interactions by exhibiting, for example, different hysteresis of the field-dependent magnetization. The magnetoferritin–dendron assemblies can be efficiently disassembled by a short optical stimulus resulting in release of free magnetoferritin particles. After the triggered release the nanomagnetic properties of the pristine magnetoferritin nanoparticles are regained.