Institute of Advanced Materials and Flexible Electronics (IAMFE), School of Chemistry and Materials Science, Nanjing University of Information Science & Technology, 210044, Nanjing, China.
Institute of Advanced Materials and Flexible Electronics (IAMFE), School of Chemistry and Materials Science, Nanjing University of Information Science & Technology, 210044, Nanjing, China.
Talanta. 2024 May 15;272:125773. doi: 10.1016/j.talanta.2024.125773. Epub 2024 Feb 14.
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.
贵金属纳米结构和光子晶体（PhC）已被广泛研究作为构建表面增强电化学发光（SE-ECL）生物传感器的基底。然而，它们的应用受到表面等离子体共振（SPR）增强强度的限制和光增强效应的不完全机制的阻碍。因此，开发具有更好信号增强能力的新型 SE-ECL 策略，丰富我们对高效生物分析的内在机制的理解是非常紧迫的。在这里，提出了一种协同 SE-ECL 策略，用于灵敏地测定前列腺特异性抗原（PSA）蛋白。随机排列的聚苯乙烯（r-PS）球和 PS PhC 阵列被应用于增强硫化镉量子点（CdS QDs）的 ECL 发射，结果表明 PhC 阵列的强度（0.22）优于 r-PS 界面（0.10）。金纳米粒子（NPs）被引入到两种表面上，并进一步增强了 ECL 强度。根据 ECL 测量结果，在 r-PS 表面修饰的 Au NPs 仅略有增加（0.13），而 PhC 阵列则显示出约 5 倍的增强（0.92），这得益于协同增强。有限差分时间域（FDTD）模拟表明，ECL 增强归因于 PS PhC 和 Au NPs 表面的耦合电磁场（EM）。SE-ECL 可以实现从 1 pg/mL 到 1 μg/mL 的检测范围，检测限为 0.41 pg/mL（S/N = 3）。本研究首次将 PhC 阵列和金属表面等离子体纳米结构结合在一起，用于协同增强 SE-ECL 系统。它为先进的 ECL 生物传感器的合理设计开辟了新的途径，并为临床诊断展示了广阔的前景。
