Institut national de la recherche scientifique, Centre - Energie, Matériaux et Télécommunications, 1650, Boul. Lionel Boulet, Varennes, Québec J3X 1S2, Canada.
Analyst. 2013 Aug 7;138(15):4378-84. doi: 10.1039/c3an36883a. Epub 2013 Jun 5.
A graphene-based label-free voltammetric immunosensor for the sensitive detection of the egg white allergen ovalbumin has been developed. Graphene-modified screen printed carbon electrodes have been covalently functionalized using electrochemical reduction of in situ generated aryl diazonium salt forming a carboxyphenyl film on the graphene surface. The blocking property of the carboxyphenyl film grafted on to the graphene electrodes using different cyclic voltammetry cycles has been characterized using differential pulse voltammetry in Fe(CN)6 solution. Then, the terminal carboxylic groups on the graphene surface were activated using EDC/NHS and used to immobilize the ovalbumin antibody and construct the immunosensor. The fabrication steps of the immunosensor have also been characterized using differential pulse voltammetry. The decrease in the Fe(CN)6 reduction peak current after the immunochemical reaction with ovalbumin has been used for the ovalbumin detection. The developed immunosensor has been used for ovalbumin detection in the concentration range of 1 pg mL(-1) to 0.5 μg mL(-1) with a detection limit of 0.83 pg mL(-1) in PBS buffer. The food matrix effect studied with ovalbumin spiked cake extract showed a good percentage of recovery, indicating the possible applicability of the developed immunosensor in real food samples.
一种基于石墨烯的无标记伏安免疫传感器已被开发用于敏感检测蛋清过敏原卵清蛋白。通过电化学还原原位生成的芳基重氮盐，将石墨烯修饰的丝网印刷碳电极共价功能化，在石墨烯表面形成羧基苯层。使用不同的循环伏安循环对在石墨烯电极上接枝的羧基苯层的阻断性能进行了特征描述，使用差分脉冲伏安法在Fe(CN)6溶液中进行了特征描述。然后，使用 EDC/NHS 激活石墨烯表面上的末端羧酸基团，用于固定卵清蛋白抗体并构建免疫传感器。使用差分脉冲伏安法对免疫传感器的制备步骤进行了特征描述。与卵清蛋白发生免疫化学反应后，Fe(CN)6还原峰电流的降低被用于卵清蛋白的检测。该开发的免疫传感器已用于在 PBS 缓冲液中浓度范围为 1 pg mL(-1)至 0.5 μg mL(-1)的卵清蛋白检测，检测限为 0.83 pg mL(-1)。用卵清蛋白掺杂蛋糕提取物研究食物基质效应显示出良好的回收率百分比，表明开发的免疫传感器在实际食品样品中的适用性。
