Key Laboratory of Interface Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, China.
Mikrochim Acta. 2019 Aug 5;186(9):606. doi: 10.1007/s00604-019-3709-x.
A sandwich-type electrochemiluminescence (ECL) immunosensor for the N-terminal brain natriuretic peptide (NT-proBNP) is described. The assay is based on the quenching of the ECL of graphite-like carbon nitride (g-CN) by polydopamine (PDA). Two-dimensional g-CN is grown in-situ on titanium dioxide nanoflowers (TiO NFs). The macroporous structure of the NFs enhances the interfacial stability of g-CN, and also promotes the ECL reaction of g-CN with the co-reactant. The introduction of gold nanoparticles into the matrix further enhances the ECL and facilitates the immobilization of capture antibodies. The nanoquencher used to label the secondary antibody is synthesized by catalytic polymerization of dopamine in the presence of bimetallic NiPd nanoparticles. The nanoquencher preserves the high reactivity of polydopamine and quenches the ECL of the g-CN/TiO system. Compared to other methods, the detection limit for NT-proBNP is decreased to 50 fg∙mL. Graphical abstract Schematic presentation of the electrochemiluminescence (ECL) process of the immunosensor: titanium dioxide nanoflowers@graphite-like carbon nitride-gold nanoparticles (TiO NFs@g-CN-Au) as luminophor, and polydopamine (PDA) as nanoquencher.
夹心型电化学发光（ECL）免疫传感器用于检测 N 端脑利钠肽（NT-proBNP）。该分析方法基于石墨相氮化碳（g-CN）的电化学发光（ECL）被聚多巴胺（PDA）猝灭。二维 g-CN 原位生长在二氧化钛纳米花（TiO NFs）上。NFs 的大孔结构增强了 g-CN 的界面稳定性，也促进了 g-CN 与共反应物的 ECL 反应。金纳米粒子的引入进一步增强了 ECL，并有利于捕获抗体的固定化。用于标记二抗的纳米猝灭剂是在双金属 NiPd 纳米粒子存在的条件下通过多巴胺的催化聚合合成的。纳米猝灭剂保持了聚多巴胺的高反应性，并猝灭了 g-CN/TiO 体系的 ECL。与其他方法相比，NT-proBNP 的检测限降低至 50 fg·mL。
