The investigation of frequency response for the magnetic nanoparticulate assembly induced by time-varied magnetic field
1 State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096, PR China
2 Jiangsu Key Laboratory of Biomaterials and Devices, Southeast University, Nanjing 210096, PR China
3 Center of Materials Analysis, Nanjing University, Nanjing, 210093, PR China
Nanoscale Research Letters 2011, 6:453 doi:10.1186/1556-276X-6-453Published: 14 July 2011
The field-induced assembly of γ-Fe2O3 nanoparticles under alternating magnetic field of different frequency was investigated. It was found that the assembly was dependent upon the difference between colloidal relaxation time and field period. The same experiments on DMSA-coated γ-Fe2O3 nanoparticles exhibited that the relaxation time may be mainly determined by the magnetic size rather than the physical size. Our results may be valuable for the knowledge of dynamic assembly of colloidal particles.