Gastric cancer (GC) was one of the most common cancers with high mortality. The detection of GC peritoneal metastasis had important significance. In this work, we have developed the novel electrochemiluminescence (ECL) biosensor to detect microRNA in GC extracellular vesicle (EV). Firstly, in situ growth of Cu nanocluster (Cu NC) on the metal-organic frameworks (MOFs) nanosheet was achieved successfully. Due to the confinement effect, Cu NCs in the porous structure of Zn MOF possessed the high quantum yield and good stability. Meanwhile, Zn MOF provided good electrochemical activity for the ECL reaction. Furthermore, the nanosized MOFs did not only act as sensing platform to load Cu NCs and link biomolecules, but also reduce steric hindrance effect for biomolecular recognition. Additionally, Au NPs/MXene and phospholipid layer were prepared and modified on the electrode, which can regulate electron transfer and improve the target recognition efficiency. The Cu NCs/Zn MOF nanosheet-based ECL sensor was employed to detect miRNA-421 from 1 fM to 1 nM with a detection limit of 0.5 fM. Finally, extracellular vesicles form clinic GC patient ascites were extracted and analyzed. The results showed that the constructed biosensor can be used for the GC peritoneal metastasis diagnosis.

中文翻译：

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基于纳米簇/金属有机框架纳米片的受限 ECL 增强生物传感器用于细胞外囊泡检测

胃癌（GC）是最常见的癌症之一，死亡率很高。 GC腹膜转移的检测具有重要意义。在这项工作中，我们开发了新型电化学发光（ECL）生物传感器来检测GC细胞外囊泡（EV）中的microRNA。首先，成功实现了金属有机框架（MOF）纳米片上铜纳米簇（Cu NC）的原位生长。由于限域效应，Zn MOF多孔结构中的Cu NCs具有高量子产率和良好的稳定性。同时，Zn MOF为ECL反应提供了良好的电化学活性。此外，纳米级MOF不仅可以作为负载Cu NCs和连接生物分子的传感平台，还可以减少生物分子识别的空间位阻效应。此外，在电极上制备并修饰了Au NPs/MXene和磷脂层，可以调节电子传递并提高目标识别效率。采用基于 Cu NCs/Zn MOF 纳米片的 ECL 传感器检测 1 fM 至 1 nM 的 miRNA-421，检测限为 0.5 fM。最后，提取临床GC患者腹水中的细胞外囊泡并进行分析。结果表明构建的生物传感器可用于GC腹膜转移的诊断。