以金纳米颗粒-二氧化钛纳米线阵列为支架的电化学免疫传感的构建及其应用  

Construction of an electrochemical immunosensor based on Au nanoparticles-TiO_2 nanowire arrays and its application

作　　者：霍小鹤 刘培培[1] 刘小强[1] 刘锦[1] 

机构地区：[1]河南大学化学化工学院,河南开封475004

出　　处：《化学研究》2017年第1期113-119,共7页Chemical Research

基　　金：国家自然科学基金(U1504215)

摘　　要：首先以掺杂氟的二氧化锡导电玻璃为基片,采用水热法制备出二氧化钛纳米线阵列,然后使用电化学沉积法将金纳米颗粒修饰于二氧化钛纳米线阵列表面以增强其导电性和生物相容性.将纳米金-二氧化钛纳米线阵列用作电化学免疫传感器支架,利用纳米金与癌胚抗原抗体之间的静电吸附作用,将包被抗体负载于电极表面制得检测癌胚抗原的电流型免疫传感器.同样,水热法还被用于制备圆柱形二氧化钛纳米棒,以辛二酸双(3-磺基-N-羟基琥珀酰亚胺酯)钠盐为双氨基交联剂,将辣根过氧化物酶和信号抗体一起固定于二氧化钛纳米棒表面作为示踪标记物.扫描电子显微镜、透射电子显微镜和X射线衍射分析仪均被用于分析上述材料的结构、形貌和组成.通过夹心型免疫反应,示踪标记物上信号抗体被定量负载于免疫传感器表面.通过一个以过氧化氢为媒介体的辣根过氧化物酶催化反应,差示脉冲伏安法被用于癌胚抗原的定量测定.结果表明,该癌胚抗原免疫传感器线性范围为0.01~120μg/L,检测限为6 ng/L.Initially,TiO2 nanowire arrays（ Ti NW） were synthesized on a F doped SnO2（ FTO） substrate through a facile hydrothermal method. With an electrochemical deposition method,gold nanoparticles（ GNPs） were modified on the Ti NW surface to enhance the conductivity and biocompatibility.Then,capture antibody（ Ab1） was immobilized on the surface of electrode via electrostatic interaction between GNPs and Ab1. With BSA used to block possible remaining active sites against nonspecific adsorption,the amperometric immunosensor was prepared successfully. Hydrothermal method was also used to prepare cylinder-shaped TiO2 nanorods,on which horseradish peroxidase（ HRP） and signal antibody（ Ab2） were immobilized to form the tracing labels. Bis（ sulfosuccinimidyl） suberate sodium salt（ BS3） was used as double amino crosslinking agent. Scanning electron microscopy（ SEM）,transmission electron microscope（ TEM）,and X-ray diffraction（ XRD） were used to survey the structure,morphology and composition of the above materials. After a sandwich-type immunoreaction,the tracing labels were quantitatively captured on the immunosensor surface to generate electrochemical signals through a H2O2 mediated HRP catalytic reaction. A linear range between 0. 01 μg/L and 120 μg/L with a detection limit of 6 ng/L were obtained by differential pulse voltam-metry（ DPV） for the quantitative determination of carcinoembryonic antigen.

关 键 词：二氧化钛纳米线阵列 电化学沉积法 金纳米颗粒 夹心型免疫反应 癌胚抗原 

分 类 号：O657.1[理学—分析化学]