In this study, a novel potential-resolved ratiometric electrochemiluminescence (ECL) sensor, using Ru(bpy)₃²⁺ doped TiO₂ nanoparticles (TiO₂-Ru(bpy)₃²⁺ NPs) with polyethyleneimine (PEI) capped CdS quantum dots (PEI-CdS QDs) as new ECL emitter unit and molecularly imprinted polymer (MIP) as recognition element, was proposed for the first time. Owing to the large specific surface area and porosity of TiO₂ NPs plentiful Ru(bpy)₃²⁺ was well immobilized on them. The obtained TiO₂-Ru(bpy)₃²⁺ NPs were able to catalyze the reduction of coreactant H₂O₂ of PEI-CdS QDs, while the PEI-CdS QDs could serve as the coreactant of TiO₂-Ru(bpy)₃²⁺ NPs, thus their ECL was promoted by each other. Additionally, graphene oxide (GO) was used to facilitate the electron transfer and sialic acid (SA) imprinted poly(3-aminophenylboronic acid) was electrodeposited on the resulting GO/TiO₂-Ru(bpy)₃²⁺@PEI-CdS/GCE. When SA concentration increased the anodic ECL signal from TiO₂-Ru(bpy)₃²⁺ NPs increased, while the cathodic ECL signal from PEI-CdS QDs declined. The sensor exhibited high sensitivity, selectivity and stability. Under the optimized conditions, the linear range was 1.0 nM - 0.1 mM and the detection limit was low to 0.017 nM (S/N = 3). Its good practical feasibility was confirmed by detecting SA in real samples with satisfactory results.

在这项研究中，一种新型的电位分辨比例电化学发光（ECL）传感器，使用Ru（bpy）₃ ²⁺掺杂的TiO ₂纳米颗粒（TiO ₂ -Ru（bpy）₃ ²⁺ NPs）和聚乙烯亚胺（PEI）封端的CdS量子点（PEI-CdS QDs）作为新的ECL发射单元，并首次提出了分子印迹聚合物（MIP）作为识别元件。由于TiO ₂ NPs的比表面积和孔隙率大，大量Ru（bpy）₃ ²⁺被很好地固定在它们上。所获得的TiO ₂ -Ru（bpy）₃ ²⁺ NPs能够催化共反应剂H ₂ O的还原₂ PEI-硫化镉量子点，而PEI-硫化镉量子点可作为二氧化钛的共反应物₂ -Ru（BPY）_3级²⁺的NP，因此它们的ECL通过相互促进。此外，使用氧化石墨烯（GO）促进电子转移，并在所得GO / TiO ₂ -Ru（bpy）₃ ²⁺ @ PEI-CdS /上电沉积唾液酸（SA）印迹的聚（3-氨基苯基硼酸）。GCE。当SA浓度增加时，来自TiO ₂ -Ru（bpy）₃ ²⁺的阳极ECL信号增加NPs增加，而PEI-CdS QDs的阴极ECL信号下降。该传感器具有高灵敏度，选择性和稳定性。在最佳条件下，线性范围为1.0 nM-0.1 mM，检出限低至0.017 nM（S / N = 3）。通过在真实样品中检测SA确认了其良好的实践可行性，并获得了令人满意的结果。