基于PoPD-MWCNTs-离子液体／纳米金的髓过氧化物酶免疫传感器

Immunosensor for Myeloperoxidase Based on PoPD-MWCNTs-Ionic Liquid/Nanogold Modified Au Electrode

在离子液体([EMIM]Br)中,将聚邻苯二胺(PoPD)-多壁碳纳米管(MWCNTs)复合物原位电聚合到金电极(Au)表面,利用纳米金固载髓过氧化物酶(MPO)抗体,构建了一种用于MPO检测的无需标记的电流型免疫传感器.采用循环伏安法(CV)和扫描电子显微镜(SEM)对修饰过程进行表征.探讨了邻苯二胺单体浓度、pH、孵育时间和孵育温度对该免疫传感器性能的影响.实验结果表明,该传感器在最适条件下对MPO响应良好,其线性范围为0.25～350 ng/mL,线性相关系数为0.9985,检出限为0.07 ng/mL.该电流型免疫传感器具有稳定性好、灵敏度较高、特异性好、结果准确可靠和可再生等优点,可应用于临床检测.

A novel label-free amperometric immunosensor for the determination of myeloperoxidase （MPO） based on poly-o-phenylenediamine （PoPD）-multi-wall carbon nanotubes （MWCNTs）-ionic liquid/ gold nanoparticles （nanogold） modified gold electrode （Au） was constructed. Firstly, a PoPD/MWNTs composite modified Au electrode was prepared in situ electropolymerization using ionic liquid as the supporting electrolyte. Then gold nanoparticles were adsorbed onto the electrode surface through amino-groups on the composite membrane for immobilization of MPO antibody via amine-Au affinity. The modification process was characterized by cyclic voltammetry （CV） and scanning electron microscope （SEM）. The factors possibly influenced the performance of the proposed immunosensor were studied in detail. Under optimal conditions, the obtained immunosensor exhibited good electrochemical behavior to MPO in a linear range of 0.25 to 350 ng/mL （r=0.9985）, with a detection limit of 0.07 ng/mL. The immunosensor has advantages of good stability, regeneration, high sensitivity and specificity. Thus, the method can be used for clinical application of MPO analysis.