Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, International Joint Research Center for Photoresponsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu, 214122, China.
Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, International Joint Research Center for Photoresponsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu, 214122, China.
Biosens Bioelectron. 2022 Jan 15;196:113733. doi: 10.1016/j.bios.2021.113733. Epub 2021 Oct 28.
Strong and stable electrochemical beacons are critical for the achievement of sensitive and reliable electroanalysis applications. In this work, the electrochemical oxidation performance of AuPt NPs was studied and firstly found to be largely enhanced under light illumination. Plasmonic AuPt NPs collected light energy after local surface plasmon resonance (LSPR) excitation and generated much more holes to participate in the electrochemical oxidation process of Pt in AuPt NPs. AuPt NPs with the electrochemical oxidation peak at around -0.7 V were utilized as detection probes for the fabrication of ratiometric electrochemical aptasensor, by introducing Co-MOF/FeO/Ag nanosheets (NSs) with the electrochemical oxidation peak at 0.1 V as reference beacons. The aptamers of epithelial cell adhesion molecule (EpCAM) modified AuPt NPs were assembled with Co-MOF/FeO/Ag NSs, which generated strong detection and reference signals at -0.7 V and 0.1 V, respectively. The high affinity between EpCAM and aptamers induced the separation of AuPt NPs from Co-MOF/FeO/Ag NSs, resulting in the decrease of detection signal at -0.7 V and unchanged reference signal at 0.1 V. A ratiometric electrochemical aptasensor was achieved for the sensitive and reliable quantification of EpCAM in the range from 100 pg/mL to 100 ng/mL. The limit of detection (LOD) was calculated to be 13.8 pg/mL for EpCAM. Plasmon-driven electrochemical oxidation enhancement principle provides the possibility for the design and fabrication of more strong and anti-interference electroactive plasmonic metal-Pt composite nanostructures for the electroanalysis applications.
强稳定的电化学信标对于实现灵敏可靠的电化学生物分析应用至关重要。在这项工作中，研究了 AuPt NPs 的电化学氧化性能，首次发现其在光照下得到了极大的增强。等离子体 AuPt NPs 在局域表面等离子体共振（LSPR）激发后收集光能，并产生更多的空穴参与 AuPt NPs 中 Pt 的电化学氧化过程。电化学氧化峰在约-0.7 V 的 AuPt NPs 被用作比率型电化学生物传感器的检测探针，通过引入电化学氧化峰在 0.1 V 的 Co-MOF/FeO/Ag 纳米片（NSs）作为参考信标。修饰有上皮细胞黏附分子（EpCAM）的适配体 AuPt NPs 与 Co-MOF/FeO/Ag NSs 组装在一起，在-0.7 V 和 0.1 V 处分别产生强的检测和参考信号。EpCAM 与适配体之间的高亲和力导致 AuPt NPs 从 Co-MOF/FeO/Ag NSs 上分离，导致-0.7 V 处检测信号降低而 0.1 V 处参考信号不变。实现了用于灵敏可靠定量检测 EpCAM 的比率型电化学生物传感器，检测范围为 100 pg/mL 至 100 ng/mL。EpCAM 的检测限（LOD）计算为 13.8 pg/mL。等离子体驱动的电化学氧化增强原理为电化学生物分析应用中设计和制备更强大、抗干扰的电活性等离子体金属-Pt 复合纳米结构提供了可能。
