This study reports a surface-enhanced electrochemiluminescence (SEECL) sensor for the ultrasensitive detection of prostate-specific antigen (PSA) in human serum. First, we prepared the Au-SiO₂ core–shell nanocomposites doped with Ru(bpy)₃²⁺ (Au@SiO₂-Ru) as the ECL signal generation and amplification element of the SEECL sensor. Ru(bpy)₃²⁺ could emit ECL under the excitation of an electrochemical reaction, and generate the local surface plasmon resonance (LSPR) electromagnetic field from the gold nanoparticle (AuNP) core. The produced LSPR then effectively enhanced the ECL signals. This sensing strategy was utilized for the detection of PSA, which can be absorbed on the electrode surface by the reaction between PSA and monoclonal antibodies. When polyclonal antibody-modified Au@SiO₂-Ru was added, the PSA-double-antibody sandwich structure was formed on the electrode surface and thus, the Au@SiO₂-Ru were quantitatively immobilized on the electrode surface. The results show that this kind of SEECL sensor has good selectivity toward PSA. Notably, the minimum detection concentration reached 7 × 10⁻⁷ ng mL⁻¹ under the optimum experimental conditions, which is much better than most of the previously reported approaches for the detection of PSA in serum.

中文翻译：

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一种表面增强的电化学发光传感器，基于Ru（bpy）32+掺杂的Au-SiO2核壳纳米复合材料，用于超灵敏检测人血清中的前列腺特异性抗原。

这项研究报告了一种表面增强的电化学发光（SEECL）传感器，用于超灵敏地检测人血清中的前列腺特异性抗原（PSA）。首先，我们制备了掺有Ru（bpy）₃ ²⁺（Au @ SiO ₂ -Ru）的Au-SiO ₂核壳纳米复合材料，作为SEECL传感器的ECL信号产生和放大元件。Ru（bpy）₃ ²⁺可以在电化学反应的激发下发出ECL，并从金纳米粒子（AuNP）核产生局部表面等离子体共振（LSPR）电磁场。然后，生成的LSPR有效地增强了ECL信号。该传感策略用于PSA的检测，可通过PSA和单克隆抗体之间的反应将其吸附在电极表面上。当添加多克隆抗体修饰的Au @ SiO ₂ -Ru时，在电极表面上形成了PSA-双抗体夹心结构，因此，Au @ SiO ₂ -Ru被定量地固定在电极表面上。结果表明，这种SEECL传感器对PSA具有良好的选择性。值得注意的是，最低检测浓度达到7×10 ^-7ng mL ^-1在最佳实验条件下，比以前报道的大多数检测血清PSA的方法要好得多。