通过化学共沉法和表面功能化修饰得到硫酸软骨素钠和Fe3+负载的磁性纳米粒子Fe3O4-CS@Fe3+(CMNP@Fe3+),并对该粒子的形貌等特性进行分析.透射电子显微镜观察显示CMNP@Fe3+呈尺寸为20 nm的圆球形,分散性较好;磁滞回线结果表明该粒子具有超顺磁性;傅里叶变换红外光谱测定证明硫酸软骨素钠和Fe3+已成功修饰在Fe3O4表面.利用磁性纳米粒子表面Fe3+与卵黄高磷蛋白的强结合力,建立从蛋黄中磁性分离卵黄高磷蛋白的新方法,并对吸附过程的影响因素进行研究.结果发现当溶液pH 4.0、底物初始质量浓度10 mg/mL、吸附时间180 min时,磁性纳米粒子的吸附能力最强.利用动力学模型和等温吸附模型进行拟合,确定CMNP@Fe3+吸附卵黄高磷蛋白的过程符合伪二级动力学模型和Freundlich等温吸附模型,并通过模型计算得到吸附平衡时卵黄高磷蛋白的理论吸附量为625.00 mg/g.该研究结果为鸡蛋中蛋白质实现磁性分离提供了依据.%Functional magnetic nanoparticles Fe3O4-CS@Fe3+ (CMNP@Fe3+ for short) were prepared by chemical co-precipitation and functional modification with sodium chondroitin sulfate and ferric ion,and their surface morphology was analyzed.CMNP@Fe3+ showed a spherical shape with a small diameter of about 20 nm,and they could be well dispersed in aqueous solution as proved by transmission electron microscope.It was found that the nanoparticles had superparamagnetic properties as indicated by the hysteresis loop.Fourier transform infrared spectrum revealed that sodium chondroitin sulfate and Fe3+coated the surface of Fe3O4 successfully.This study established a new method to extract phosvitin from hen egg yolk by taking advantage of the strong binding of Fe3+ on the surface of magnetic nanoparticles to phosvitin,and we also investigated the factors influencing the adsorption process.The magnetic nanoparticles had maximum adsorption capacity under the following conditions:solution pH 4.0,initial substrate concentration 10 mg/mL,and adsorption time 180 min.The adsorption kinetics of CMNP@Fe3+ for phosvitin was better described by a pseudo second-order kinetic model,and the theoretical adsorption capacity at the equilibrium state computed from the model was 625.00 mg/g.The adsorption data were fit to well the Freundlich isotherm model.This research may provide a reference for protein separation from eggs using magnetic particles.
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