Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China.
Biosens Bioelectron. 2018 Nov 30;120:1-7. doi: 10.1016/j.bios.2018.08.026. Epub 2018 Aug 13.
An ultrasensitive label-free photoelectrochemical (PEC) immunosensor with high visible-light activity was developed for quantitative detection of amyloid β-protein (Aβ) by cross-linking anti-Aβ antibody onto the AgS sensitized SnO/SnS nanocomposites. Specifically, SnO with flower-like porous nanostructure was innovatively applied in PEC immunosensor as a basal material. It could form a heterostructure with SnS, which brought about the sensitization of SnO and enhanced the separation of photogenerated electrons and holes. Moreover, AgS was in-situ growth on the surface of SnO/SnS, which further enhanced the photocurrent response significantly. Therefore, SnO/SnS/AgS could form stepwise band-edge structure, which benefited the light harvesting and provided a good foundation for sensor construction and detection. Under optimal conditions, the PEC immunosensor was used to detect the content of Aβ and exhibited a wide linear concentration range from 0.5 pg mL to 100 ng mL, with low limit of detection (0.17 pg mL) and limit of quantification (0.56 pg mL). Additionally, the designed PEC immunosensor exhibited good reproducibility, specificity, and stability which may find potential applications in the biosensor, biomedicine, clinical diagnosis, photocatalysis and other related fields.
一种超灵敏的无标记光电化学（PEC）免疫传感器，具有高光活性，通过将抗 Aβ 抗体交联到 AgS 敏化的 SnO/SnS 纳米复合材料上，用于定量检测淀粉样 β 蛋白（Aβ）。具体而言，创新性地将具有花状多孔纳米结构的 SnO 应用于 PEC 免疫传感器作为基底材料。它可以与 SnS 形成异质结，从而敏化 SnO 并增强光生电子和空穴的分离。此外，AgS 原位生长在 SnO/SnS 的表面，进一步显著增强了光电流响应。因此，SnO/SnS/AgS 可以形成逐步能带边缘结构，有利于光捕获，并为传感器构建和检测提供了良好的基础。在最佳条件下，该 PEC 免疫传感器用于检测 Aβ 的含量，表现出从 0.5 pg mL 到 100 ng mL 的宽线性浓度范围，检测限低（0.17 pg mL），定量限（0.56 pg mL）。此外，设计的 PEC 免疫传感器表现出良好的重现性、特异性和稳定性，可能在生物传感器、生物医学、临床诊断、光催化和其他相关领域有潜在的应用。
