磁性羟基磷灰石复合物的制备与表征

为探索磁性颗粒在治疗因缺乏骨骼应有的应力刺激而导致骨质疏松方面的潜在应用,研究制备了兼具良好生物活性和超顺磁性的羟基磷灰石(HA)/Fe3O4复合物。以化学沉积法合成的纳米Fe3O4浆料为底物,在Ca、P溶液中通过尿素酶催化水解尿素缓慢升高pH值,从而使HA逐渐在Fe3O4上沉积,形成具有一定核壳结构的磁性HA复合物。利用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、X射线能量色散谱仪(EDX)、振动样品磁强计(VSM)和磁铁对底物及试样进行了表征。结果表明,以纳米Fe3O4浆料为底物,一定浓度含氯化钠的Ca、P溶液(Ca、P原子比为5∶3,Ca、Fe原子比为5∶3)为媒介,在37℃水浴中,反应48h,可制得具有较好磁性能的HA复合物,其饱和磁化强度可达7.23A.m2/kg,剩磁为0.073A.m2/kg,矫顽力为261.08A/m。

Preparation and characterization of the magnetic hydroxyapatite composite

For the purpose of exploring the potential application of magnetic hydroxyapatite(HA) composite particles in treatment the osteoporosis due to lack of stress stimulus,a novel method was employed to fabricate HA/Fe3O4 composite particles with good bioactivity and superparamagnetism.The nano-iron oxide(Fe3O4) slurry synthesized by chemical precipitation was used as substrate in Ca,P solution to deposite HA on the Fe3O4 spheres through slowly increase of pH by decomposition of urea using urease as the catalytic.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray energy dispersive spectroscopy(EDX),vibrating sample magnetometer(VSM) and the magnet were used to characterize the substrate and the resultant samples.The results show that:it’s a good method to prepare the superparamagnetic hydroxyapatite composite which has better magnetic performance by using the nano-iron oxide(Fe3O4) slurry as substrate and the Ca,P solution of certain concentration(the Ca/P ratio of 5∶3;Ca/Fe ratio of 5∶3) containing the sodium chloride as the media,reacting in water bathing at 37 ℃ for 48h.The saturated magnetization(Ms) of the composite sample is 7.23A·m2/kg,the remanence(Mr) is 0.073A·m2/kg and the coercivity(Hc) is 261.08A/m.