无标记检测CD4~+T淋巴细胞的免疫传感器构建

目的构建一种无标记检测CD4~+T淋巴细胞的免疫传感器。方法采用葡萄球菌A蛋白(SPA)法定向固定单克隆抗体于金叉指微阵列电极表面以捕获CD4~+T淋巴细胞,并用循环伏安法(CV)扫描对金叉指微阵列电极表面的修饰情况进行表征,最后通过电化学交流阻抗谱法(EIS)对免疫传感器捕获的CD4~+T淋巴细胞进行阻抗检测,通过等效电路拟合获得的阻抗值变化绘制标准曲线。结果该免疫传感器检测CD4~+T淋巴细胞的线性范围是(5.0×103-5.0×106)/mL,检测下限为5.0×102/mL。结论该免疫传感器的结果准确可靠,检测过程简便,价格低廉,有望用于实时检测系统,为实现快速、准确、价廉的CD4~+T淋巴细胞分类计数提供帮助。

Immunosensor construction of label free detection of CD4+T lymphocytes

Objective To construct an immunosensor for detecting CD4+ T lymphocytes without labeling .Methods The staphy-lococcus protein A(SPA) method was adopted to conduct the oriented immobilization of CD4 monoclonal antibodies on the gold in-terdigitated microelectrode surface for capturing CD4+ T lymphocytes .Then cyclic voltammetry(CV) method was used to conduct the representation of modification situation on the gold interdigitated microelectrode surface .Finally the electrochemical impedance spectroscopy(EIS) was used to detect the impedance of CD4+ T lymphocytes captured by the immunosensor .The standard curve was drawn by the impedance values change obtained by the equivalent electric circuit fitting .Results The linear range of this im-munosensor for detecting CD4+ T lymphocytes was (5 × 103 -5 .0 × 106 )/mL ,with lower detection limit of 5 .0 × 102/mL .Conclu-sion The constructed immunosensor has accurate and reliable detection results uhidn is simple to operate accurate ,convenient and cheap ,which might be expected to be used in the real-time detection system ,and offers help for realizing rapid ,accurate and inex-pensive CD4+ T lymphocyte count .