Surface-enhanced Electrochemiluminescence Sensor Based on Au-SiO2 core-shell nanocomposites doped with Ru(bpy)32+ for Ultrasensitive Detection of Prostate specific Antigen in Human Serum
This work reports a surface-enhanced electrochemiluminescence (SEECL) sensor for ultrasensitive detection of prostate specific antigen (PSA) in human serum. Firstly, we prepared the Au-SiO2 core-shell nanocomposites doped with Ru(bpy)32+ (Au@SiO2-Ru) as ECL signal generation and amplification element of the SEECL sensor. Ru(bpy)32+ could emit ECL under the excitation of electrochemical reaction, and generate the local surface plasmon resonance (LSPR) electromagnetic field frim the gold nanoparticle (AuNP) core. The produced LSPR would then effectively enhance the ECL signals. This sensing strategy was utilized for the detection of PSA. PSA was absorbed on the electrode surface modified with monoclonal antibody. When the addition of polyclonal antibody modified Au@SiO2-Ru, the PSA-double-antibody sandwich structure formed, thus Au@SiO2-Ru were quantitative immobilized on electrode surface. The results show that this kind of SEECL sensor has good selectivity to PSA. Notably, the minimum detection concentration could be reached 7×10-7 ng/mL under the optimum experimental conditions, which is much better than most of the previously reported approaches for the detection of PSA in serum.
- This article is part of the themed collection: Versatile Electrochemical Approaches