论文部分内容阅读
建立了一种可同时检测双组分肿瘤标志物的免标记电化学免疫测定方法,检测了人血清样品中癌胚抗原(CEA)和甲胎蛋白(AFP)的含量.在实验中,我们首先将二种电化学底物,二茂铁甲酸(FCA)和亚甲基蓝(MB),分别结合在离子液体(IL)修饰的介孔硅(MPS)的孔道内,制备FCA-IL-MPS和MB-IL-MPS复合材料;然后将免疫探针涂覆在掺铟氧化锡(ITO)电极表面的不同部分;最后将CEA单克隆抗体(anti-CEA)和AFP单克隆抗体(anti-AFP)分别负载到两种材料的孔内,制得CEA和AFP的免标记免疫探针(anti-CEA/FCA-IL-MPS,anti-AFP/MB-IL-MPS),组装得到双组分的免标记免疫传感器.当该免疫传感器在含有抗原的样液中温育后,CEA和AFP抗原通过特异性免疫反应而结合到MPS孔道内.由于形成的免疫复合物不导电且有一定的空间位阻,所以对电极表面的电子转移产生了阻碍.根据ITO不同位置上响应电流的变化实现对CEA和AFP含量的同时测定.本方法对CEA和AFP的检测线性范围分别为0.5~80 ng?mL-1和0.5~100 ng?mL-1,检测限分别为0.1 ng?mL-1和0.1 ng?mL-1(S/N=3).离子液体具有高导电率,能实现所构建体系信号的放大,使制备的免疫传感器具有良好的灵敏度.
A novel immunoassay for label-free detection of two-component tumor markers was established to detect the content of carcinoembryonic antigen (CEA) and alpha-fetoprotein (AFP) in human serum samples.In the experiment, Two kinds of electrochemical substrates, ferrocene carboxylic acid (FCA) and methylene blue (MB) were respectively incorporated in the pores of the ion liquid (IL) -modified mesoporous silica (MPS) to prepare FCA-IL-MPS and MB- IL-MPS composite material; and then immunoprobe was coated on different parts of the surface of the indium tin oxide (ITO) electrode; finally, the anti-CEA and anti-AFP antibodies were respectively loaded Immunofluorescent probes (anti-CEA / FCA-IL-MPS, anti-AFP / MB-IL-MPS) of CEA and AFP were prepared in the wells of both materials to assemble a two- Sensor. When the immunosensor is incubated in a sample-containing antigen, the CEA and AFP antigens bind to the MPS pore via a specific immunoreaction. Since the immune complexes formed are not electrically conductive and have steric hindrance, The electrode surface of the electron transfer has hindered.According to ITO in different positions of the response to changes in the current CEA and AFP content at the same time The linear range of this method for CEA and AFP was 0.5 ~ 80 ng? ML-1 and 0.5 ~ 100 ng? ML-1 with the detection limits of 0.1 ng? ML-1 and 0.1 ng? ML-1 respectively S / N = 3) .Ionic liquid has high conductivity, which can amplify the signal of the constructed system and make the prepared immunosensor have good sensitivity.