标题：A network signal amplification strategy of ultrasensitive photoelectrochemical immunosensing carcinoembryonic antigen based on CdSe/melamine network as label
作者：Li, Jiaojiao ;Zhang, Yong ;Kuang, Xuan ;Wang, Zhiling ;Wei, Qin
作者机构：[Li, Jiaojiao ;Zhang, Yong ;Kuang, Xuan ;Wang, Zhiling ;Wei, Qin ] Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong (Univer 更多
来源：Biosensors and Bioelectronics
摘要：Taking advantage of CdSe/melamine network as label and Au-TiO2as substrate, this work developed a novel kind of signal amplification strategy for fabricating photoelectrochemical (PEC) immunoassay. The melamine, a star-shaped triamino molecule, was firstly used for readily capturing CdSe QDs and forming a CdSe/melamine network, which was formed through strong interactions between the carboxyl groups of TGA-stabilized CdSe QDs and the three amino groups of each melamine molecule. In this strategy, the primary antibody (Ab1) was immobilized onto Au-TiO2substrate, which made the photoelectric conversion efficiency increase significantly. After the formed Ab2-CdSe/melamine network labels were captured onto the electrode surface via the specific antibody-antigen interaction, the photoelectric activity could be further enhanced via the interaction between the Au-TiO2substrate and CdSe/melamine network. Due to this amplification of PEC signals and the special structure of the label, the fabricated PEC immunosensor was applied for sensitive and specific detection of cancer biomarker carcinoembryonic antigen (CEA), and displayed a wide linear range (0.005-1000 ng mL-1) and low detection limit (5 pg mL-1). In addition, the immunosensor was performed with good stability and reproducibility, and the results to analyze human serum samples were satisfactory.