【摘要】 采用高温热分解前驱体乙酰丙酮铁法合成了尺寸均一且分散性好的油溶性Fe3O4纳米粒子,通过表面配体置换直接将其表面换为水溶性分子聚乙二醇二酸(PEG diacid),形成了具有表面功能基的稳定无毒的水溶性磁性复合体系.TEM,M-H曲线,FTIR和TGA等表征结果表明,油溶性Fe3O4纳米粒子已成功转移至水相,且具有很好的顺磁性及生物相容性.研究结果表明,α-胰凝乳蛋白酶(α-ChT)被成功地固载到水溶性Fe3O4纳米粒子表面,与自由酶相比,固定化酶的热稳定性明显提高,并体现出良好的可重复利用性.更多还原

【Abstract】 The oil-soluble magnetic Fe3O4 nanoparticles with uniform size and morphology were synthesized via thermal decomposition of Fe(acac)3 precursor. They were successfully transferred into aqueous phase through the ligand-exchange reaction with water-soluble PEG diacid molecule,forming water-soluble,stable,nontoxic,and magnetic composite with surface functional group. TEM,M-H curve,FTIR and TGA were used to characterize the as-synthesized composite and demonstrated that the nanoparticles maintained their superparamagnetism and biocompatibility. α-Chymotrypsin(α-ChT) was immobilized on the surface of the water-soluble nanoparticles. The immobilized α-ChT exhibited better thermal stability and high activity after repeated usage.更多还原