CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

Evolution of Structural and Magnetic Properties of Magnetite Nanoparticles for Biomedical Applications

Stefan Gustafsson (Institutionen för teknisk fysik, Mikroskopi och mikroanalys ; SuMo Biomaterials) ; A. Fornara ; K. Petersson ; C. Johansson ; M. Muhammed ; Eva Olsson (Institutionen för teknisk fysik, Mikroskopi och mikroanalys)
Crystal Growth & Design (1528-7483). Vol. 10 (2010), 5, p. 2278-2284.
[Artikel, övrig vetenskaplig]

We have investigated the evolution of microstructure and magnetic properties of thermally blocked magnetite nanoparticles, aimed for immunoassay applications, during their synthesis. High-resolution transmission electron microscopy (HRTEM) investigations of the size, size distribution, morphology, and crystal structure of particles reveal that particles at an early stage of the reaction process are either single crystals or polycrystals containing planar faults and they grow via a combination of reactant (monomer) consumption and oriented attachment at specific crystallographic surfaces because of the strong dipolar character of the < 111 > surfaces of magnetite. At a later stage of the synthesis reaction, the magnetic attraction strives to align contacting particles with their < 111 > axis of easy magnetization in parallel and this may also be an active driving force for crystal growth. At latter stages, the crystal growth is dominated by Ostwald ripening leading to smoother crystalline particles with a mean diameter of 16.7 +/- 3.5 nm and a narrow size distribution. The magnetic properties of the particles measured using static and dynamic magnetic fields are consistent with the evolution of particle size and structure and show the transition from superparamagnetic to thermally blocked behavior needed for magnetic relaxation-based immunoassay applications.

Nyckelord: IMPERFECT ORIENTED ATTACHMENT, MAGNETOTACTIC BACTERIA, NANOCRYSTALLINE, ZNS, DEFECT GENERATION, GROWTH-KINETICS, CRYSTAL-GROWTH, PARTICLES, ORGANIZATION, ACCRETION, DYNAMICS



Denna post skapades 2010-05-28. Senast ändrad 2016-03-21.
CPL Pubid: 122051

 

Läs direkt!


Länk till annan sajt (kan kräva inloggning)


Institutioner (Chalmers)

Institutionen för teknisk fysik, Mikroskopi och mikroanalys (2005-2012)
SuMo Biomaterials

Ämnesområden

Teknisk fysik

Chalmers infrastruktur