Synergetic surface enhancement of quantum dots-based electrochemiluminescence with photonic crystal light scattering and metal surface plasmon resonance for sensitive bioanalysis

• Published in: Talanta (Oxford) 2024-05, Vol.272, p.125773-125773, Article 125773
• Main Authors: Lu, Haijie, Zhu, Junkai, Chen, Juncheng, Tao, Tao, Shen, Yizhong, Zhou, Hong
• Format: Article
• Language: English
• Subjects: Electrochemiluminescence; Photonic crystal; Prostate specific antigen; Surface plasmon resonance; Synergetic surface enhancement
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2024.125773

Noble metal nanostructures and photonic crystals (PhCs) have been widely investigated as substrates for constructing surface enhanced electrochemiluminescence (SE-ECL) biosensors. However, their applications are hindered by the limited enhancement intensity of surface plasmon resonance (SPR) and an incomplete mechanism for the photonic enhancement effect. Hence, developing a novel SE-ECL strategy with better signal enhanced capability and enriching our understanding of the intrinsic mechanisms for efficient bioanalysis is extremely urgent. Here, a synergistic SE-ECL strategy was developed for the sensitive determination of prostate specific antigen (PSA) protein. The randomly arranged polystyrene (r-PS) spheres and PS PhC arrays were applied to enhance the ECL emission of cadmium sulfide quantum dots (CdS QDs) and the results suggested that the PhC arrays displayed superior intensity (0.22) than the r-PS interface (0.10). Au nanoparticles (NPs) were introduced onto the two kinds of surfaces and further boosted the ECL intensity. According to the ECL measurements, Au NPs modified at the r-PS surface exhibited only a slight increase (0.13), while the PhC arrays showed approximately 5-fold enhancement (0.92), benefiting from the synergistic enhancement. The finite-difference time-domain (FDTD) simulation indicated that the ECL enhancement was ascribed to the coupled electromagnetic (EM) field at the surfaces of PS PhCs and Au NPs. The SE-ECL could achieve a detection range from 1 pg/mL to 1 μg/mL with a detection limit of 0.41 pg/mL (S/N = 3). This study provides the first combination of PhC arrays and metal surface plasmon nanostructure for the synergetic enhancement of SE-ECL systems. It opens a new avenue for the rational design of advanced ECL biosensors and shows great perspective for clinical diagnosis. Schematic illustration of the randomly arranged PS interface and the synergistically enhanced ECL biosensor. [Display omitted] •ECL performances at the PS PhCs and randomly-distributed PS spheres were discussed.•Synergetic enhancement of the QDs-based ECL with PS PhCs and Au NPs was reported.•Enhanced EM field at the surface of PS PhCs and Au NPs were simulated with FDTD.•Sensitive detection of the PSA with the synergistically enhanced ECL was realized.