State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Biosens Bioelectron. 2017 May 15;91:293-298. doi: 10.1016/j.bios.2016.12.045. Epub 2016 Dec 20.
This work reports the use of compositionally heterogeneous asymmetric Ag@Au core-satellite nanoassembly functionalized with DNA sequence as unique signaling nanoprobes for the realization of new energy-transfer-based photoelectrochemical (PEC) immunoassay of prostate- specific antigen (PSA). Specifically, the Ag@Au asymmetric core-satellite nanoassemblies (Ag@Au ACS) were fabricated on a two-dimensional glass substrate by a modified controlled assembly technique, and then functionalized with DNA sequences containing PSA aptamers as signaling nanoprobes. Then, the sandwich complexing between the PSA, its antibodies, and the signaling nanoprobes was performed on a CdS QDs modified indium tin oxide (ITO) electrode. The single stranded DNA can server as a facile mediator that place the Ag@Au ACS in proximity of CdS QDs, stimulating the interparticle exciton-plasmon interactions between Ag@Au ACS and CdS QDs and thus quenching the excitonic states in the latter. Since the damping effect is closely related to the target concentration, a novel energy-transfer-based PEC bioanalysis could be achieved for the sensitive and specific PSA assay. The developed biosensor displayed a linear range from 1.0×10gmL to 1.0×10gmL and the detection limit was experimentally found to be of 0.3×10gmL. This strategy used the Ag@Au ACS-DNA signaling nanoprobes and overcame the deficiency of short operating distance of the energy transfer process for feasible PEC immunoassay. More significantly, it provided a way to couple the plasmonic properties of the Ag NPs and Au NPs in a single PEC bioanalytical system. We expected this work could inspire more interests and further investigations on the advanced engineering of the core-satellite or other judiciously designed nanostructures for new PEC bioanalytical uses with novel properties.
这项工作报道了使用组成异质不对称的 Ag@Au 核-卫星纳米组装体，并将其功能化，使其与 DNA 序列结合，作为独特的信号纳米探针，用于实现基于新能量转移的光电化学（PEC）免疫分析前列腺特异性抗原（PSA）。具体来说，Ag@Au 不对称核-卫星纳米组装体（Ag@Au ACS）是通过改进的控制组装技术在二维玻璃基底上制备的，然后用含有 PSA 适体的 DNA 序列进行功能化，作为信号纳米探针。然后，在 CdS QDs 修饰的氧化铟锡（ITO）电极上进行 PSA、其抗体和信号纳米探针之间的三明治复合。单链 DNA 可以作为一种简单的介体，将 Ag@Au ACS 置于 CdS QDs 附近，刺激 Ag@Au ACS 和 CdS QDs 之间的粒子间激子-等离子体相互作用，从而猝灭后者的激子态。由于阻尼效应与目标浓度密切相关，因此可以实现基于新能量转移的 PEC 生物分析，用于敏感和特异的 PSA 分析。所开发的生物传感器的线性范围为 1.0×10gmL 至 1.0×10gmL，检测限实验上发现为 0.3×10gmL。该策略使用 Ag@Au ACS-DNA 信号纳米探针，克服了能量转移过程操作距离短的缺陷，实现了可行的 PEC 免疫分析。更重要的是，它为在单个 PEC 生物分析系统中结合 Ag NPs 和 Au NPs 的等离子体特性提供了一种方法。我们期望这项工作能够激发更多的兴趣，并进一步研究核心-卫星或其他明智设计的纳米结构的先进工程，用于具有新特性的新型 PEC 生物分析用途。
