表面分子印迹磁性纳米粒子的制备及其血红蛋白传感应用

以Fe₃O₄磁性纳米粒子为载体、多巴胺（DA）为功能单体、血红蛋白（Hb）为模板分子，用氯铂酸氧化DA生成聚多巴胺（PDA），同时氯铂酸还原为铂纳米粒子（PtNPs），与Hb一起负载于Fe₃O₄纳米粒子表面，洗脱Hb后合成了表面分子印迹磁性纳米粒子（印迹Fe₃O₄/PDA-PtNPs）. 将印迹Fe₃O₄/PDA-PtNPs修饰于磁性玻碳基底表面，制得印迹Fe₃O₄/PDA-PtNPs修饰电极. 实验结果表明，印迹Fe₃O₄/PDA-PtNPs具有良好的水溶性，粒径分布均匀，生成的PtNPs具有良好的导电性和刚性. 用印迹Fe₃O₄/PDA-PtNPs构建的传感器对Hb具有良好的识别性，在0.14 ~ 2.7 μg·mL^-1 Hb浓度范围与交流阻抗变化值呈良好的线性关系，检出限（S/N=3）为0.05 μg·mL^-1.

Preparation of Surface Molecularly Imprinted Magnetic Nanoparticles for Hemoglobin Sensing

Surface molecularly imprinted magnetic nanoparticles (NPs) were prepared by employing dopamine (DA) as a functional monomer, hemoglobin (Hb) as a template, H₂PtCl₆ as an oxidant triggered DA polymerization on the surface of the Fe₃O₄ NPs. The Hb and the formed platinum nanoparticles (PtNPs) were embedded into the polydopamine (PDA). After removal of the Hb, the surface molecularly imprinted magnetic nanoparticles (imprinted Fe₃O₄/PDA-PtNPs) were formed, and then simply immobilized on the magnetic glassy carbon electrode (imprinted Fe₃O₄/PDA-PtNPs/MGCE) for Hb sensing. The imprinted Fe₃O₄/PDA-PtNPs were demonstrated magnetic spherical shape with good solubility in water and narrow size distribution. The PtNPs embedded in the imprinted coating could effectively promote the conductivity and the mechanical strength of imprinted cavity. In addition, the imprinted Fe₃O₄/PDA-PtNPs/MGCE could selectively recognize Hb and was used to detect Hb in the range of 0.14 ~ 2.7 μg?mL^-1 with a detection limit of 0.05 μg?mL^-1 (S/N=3).