中国物理B ›› 2016, Vol. 25 ›› Issue (7): 77504-077504.doi: 10.1088/1674-1056/25/7/077504
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
Dan Wang(王丹), Bingbing Lin(林兵兵), Taipeng Shen(申太鹏), Jun Wu(吴君), Fuhua Hao(豪富华), Chunchao Xia(夏春潮), Qiyong Gong(龚启勇), Huiru Tang(唐惠儒), Bin Song(宋彬), Hua Ai(艾华)
Dan Wang(王丹)1, Bingbing Lin(林兵兵)1, Taipeng Shen(申太鹏)1, Jun Wu(吴君)1, Fuhua Hao(豪富华)2, Chunchao Xia(夏春潮)3, Qiyong Gong(龚启勇)3, Huiru Tang(唐惠儒)2, Bin Song(宋彬)3, Hua Ai(艾华)1,3
摘要:
Polymer-mediated self-assembly of superparamagnetic iron oxide (SPIO) nanoparticles allows modulation of the structure of SPIO nanocrystal cluster and their magnetic properties. In this study, dopamine-functionalized polyesters (DA-polyester) were used to directly control the magnetic nanoparticle spacing and its effect on magnetic resonance relaxation properties of these clusters was investigated. Monodisperse SPIO nanocrystals with different surface coating materials (poly(ε-caprolactone), poly(lactic acid)) of different molecular weights containing dopamine (DA) structure (DA-PCL2k, DA-PCL1k, DA-PLA1k)) were prepared via ligand exchange reaction, and these nanocrystals were encapsulated inside amphiphilic polymer micelles to modulate the SPIO nanocrystal interparticle spacing. Small-angle x-ray scattering (SAXS) was applied to quantify the interparticle spacing of SPIO clusters. The results demonstrated that the tailored magnetic nanoparticle clusters featured controllable interparticle spacing providing directly by the different surface coating of SPIO nanocrystals. Systematic modulation of SPIO nanocrystal interparticle spacing can regulate the saturation magnetization (Ms) and T2 relaxation of the aggregation, and lead to increased magnetic resonance (MR) relaxation properties with decreased interparticle spacing.
中图分类号: (Magnetic properties of nanostructures)