Abstract：
The photoelectrochemical immunoassay of glycogen phosphorylase BB (GPBB) was studied. A methyl orange/TiO2 nanorod heterojunction was constructed on a fluorine-doped tin oxide electrode by hydrothermal synthesis, calcination, and chemical adsorption. A sandwich immune structure consisting of GPBB as the first antibody, GPBB, and a CdS@mesoporous silica-ascorbic acid (AA)-GPBB as secondary antibody composite was constructed on each of the selected well surfaces of a 96-well microplate. By adding mercaptoethylamine to structurally destroy the secondary antibody composite and release the electron donor AA, the amplification of photocurrent, and thus the \"off-on\" photoelectrochemical biosensing of GPBB were realized. The use of the 96-well microplate provides good reproducibility of the assembled immune structures and eliminates the possible effect of the photogenerated hole-induced protein oxidation on the photocurrent. The relevant electrodes and materials were characterized by electrochemistry, UV-vis diffuse reflectance spectra, Fourier transform infrared spectroscopy, X-ray diffractometer, scanning electron microscopy/energy dispersive spectroscopy, transmission electron microscopy and BET method. Under the optimal conditions, the photocurrent was linear with the logarithm of GPBB concentration from 0.005 to 200 ng mL-1 and with a limit of detection of 1.7 pg mL-1 (S/N = 3). Satisfactory results were obtained in the analysis of real serum samples. A sandwich immune structure consisting of GPBB first antibody, GPBB, and a CdS@mesoporous silica-ascorbic acid (AA)-GPBB secondary antibody composite was constructed on each of the selected well surfaces of a 96-well microplate. By adding mercaptoethylamine to structurally destroy the secondary antibody composite and release the electron donor AA, the amplification of photocurrent, and thus the \"off-on\" photoelectrochemical biosensing of GPBB were realized.
摘要：
研究了糖原磷酸化酶BB（GPBB）的光电化学免疫测定。通过水热合成在氟掺杂的氧化锡电极上构建了甲基橙/TiO2纳米棒异质结，煅烧,和化学吸附。由GPBB作为第一抗体组成的夹心免疫结构，GPBB,在96孔微孔板的每个选定孔表面上构建CdS@介孔二氧化硅-抗坏血酸（AA）-GPBB作为第二抗体复合物。通过添加巯基乙胺在结构上破坏第二抗体复合物并释放电子供体AA，光电流的放大，从而实现了GPBB的“关”光电化学生物传感。96孔微孔板的使用提供了组装的免疫结构的良好再现性，并消除了光生空穴诱导的蛋白质氧化对光电流的可能影响。通过电化学对相关电极和材料进行了表征，紫外-可见漫反射光谱,傅里叶变换红外光谱,X射线衍射仪,扫描电子显微镜/能量色散光谱，透射电镜和BET法。在最优条件下,光电流与GPBB浓度的对数在0.005~200ngmL-1范围内呈线性关系,检测限为1.7pgmL-1(S/N=3).在实际血清样品的分析中获得了满意的结果。由GPBB第一抗体组成的夹心免疫结构，GPBB,在96孔微孔板的每个选定孔表面上构建CdS@介孔二氧化硅-抗坏血酸(AA)-GPBB二级抗体复合物。通过添加巯基乙胺在结构上破坏第二抗体复合物并释放电子供体AA，光电流的放大，从而实现了GPBB的“关”光电化学生物传感。
