miRNAs are among the novel biomarkers that can be evaluated for sensitive and early cancer diagnosis. In the present study, an electrochemical nanobiosensor has been fabricated to detect two gastric cancer (GC) related miRNAs simultaneously. By employing Au nanoparticles- and [email protected] quantum dots-contained magnetic nanocomposites as electrochemical labels along with the polythiophene/reduced graphene oxide-modified carbon electrodes, this dual signal nanobiosensor showed a considerable performance in quantifying miR-106a (a GC oncogenic miRNA) and let-7a (a GC tumor suppressor miRNA). Using cyclic voltammetry (CV) and differential pulse voltammetry (DPV), not only the accomplishment of desired biosensing platform construction was confirmed, but also its great specificity, appropriate selectivity, acceptable stability, and significant sensitivity were indicated. Through the combined analyses of the dual miRNAs, our nanobiosensor reached detection limit of 0.02 fM and 0.06 fM for let-7a and miR-106a, respectively. This multiplex PCR-free miRNA nanobiosensor demonstrates attractive potentials for promising applications in early diagnosis of GC and additionally the screen of any miRNA sequence.

miRNA是可以用于敏感和早期癌症诊断的新型生物标志物。在本研究中，电化学纳米生物传感器已被制造来同时检测两个胃癌（GC）相关的miRNA。通过使用含金纳米颗粒和[受电子邮件保护的]量子点的磁性纳米复合材料以及聚噻吩/还原的氧化石墨烯修饰的碳电极作为电化学标记，这种双信号纳米生物传感器在定量miR-106a（GC致癌miRNA）方面显示出显着的性能。 ）和let-7a（GC肿瘤抑制物miRNA）。使用循环伏安法（CV）和差分脉冲伏安法（DPV），不仅证实了所需的生物传感平台的构建成功，而且还证实了其高度的特异性，适当的选择性，可接受的稳定性，并显示出显着的敏感性。通过对双重miRNA的组合分析，我们的纳米生物传感器对let-7a和miR-106a的检测极限分别达到0.02 fM和0.06 fM。这种无多重PCR反应的miRNA纳米生物传感器在早期诊断GC和筛选任何miRNA序列中显示出诱人的潜在应用前景。