Determination of microRNAs (miRNAs) as valuable blood-borne biomarkers has attracted many scientific attentions. However, analytical methods are still restricted by miRNAs intrinsic characteristics. In this study, for the first time, novel blackberry-like magnetic DNA/FMMA nanospheres were synthesized and mounted on a gold stir-bar as signal amplification probes. To produce this strong electrochemical signal label, double strand DNAs were immobilized on gold coated magnetic nanospheres through a hybridization chain reaction followed by reversible addition-fragmentation chain-transfer polymerization, which brought a great quantity of the electroactive tags (FMMA) on the nanosphere surface. These nanospheres were then fixed on the gold stir-bar as signal probes. The magnetic DNA/FMMA nanosphere probes can be released by substituting with the newly emerging DNA fragments of catalyzed hairpin assembly products. Eventually, these signal probes were magnetically enriched on the electrode surface to produce electrochemical signal and finally, the biosensor was developed to detect miRNA-106a (model target). The suggested aptamer-based biosensor demonstrated considerable selectivity, acceptable storage stability, high specificity, and excellent performance in real sample analysis without any pretreatments. As a result, current study reveals that the developed strategy has a great potential for the early diagnosis of gastric cancer and additionally the clinical monitoring of any miRNA sequences.

microRNAs (miRNAs) 作为有价值的血源性生物标志物的测定已经引起了许多科学的关注。然而，分析方法仍然受到 miRNA 固有特性的限制。在这项研究中，首次合成了新型的类黑莓磁性 DNA/FMMA 纳米球，并将其安装在金搅拌棒上作为信号放大探针。为了产生这种强电化学信号标记，将双链 DNA 通过杂交链反应固定在镀金的磁性纳米球上，然后进行可逆的加成-断裂链转移聚合，在纳米球表面产生大量的电活性标签 (FMMA) . 然后将这些纳米球固定在金搅拌棒上作为信号探针。磁性 DNA/FMMA 纳米球探针可以通过用催化发夹组装产品的新出现的 DNA 片段替代来释放。最终，这些信号探针在电极表面被磁性富集以产生电化学信号，最后，生物传感器被开发用于检测 miRNA-106a（模型目标）。所建议的基于适配体的生物传感器在实际样品分析中表现出相当大的选择性、可接受的储存稳定性、高特异性和优异的性能，无需任何预处理。因此，目前的研究表明，所开发的策略在胃癌的早期诊断以及任何 miRNA 序列的临床监测方面具有巨大潜力。这些信号探针在电极表面进行磁性富集以产生电化学信号，最后开发了生物传感器来检测 miRNA-106a（模型目标）。所建议的基于适配体的生物传感器在实际样品分析中表现出相当大的选择性、可接受的储存稳定性、高特异性和优异的性能，无需任何预处理。因此，目前的研究表明，所开发的策略在胃癌的早期诊断以及任何 miRNA 序列的临床监测方面具有巨大潜力。这些信号探针在电极表面进行磁性富集以产生电化学信号，最后开发了生物传感器来检测 miRNA-106a（模型目标）。所建议的基于适配体的生物传感器在实际样品分析中表现出相当大的选择性、可接受的储存稳定性、高特异性和优异的性能，无需任何预处理。因此，目前的研究表明，所开发的策略在胃癌的早期诊断以及任何 miRNA 序列的临床监测方面具有巨大潜力。在实际样品分析中表现出色，无需任何预处理。因此，目前的研究表明，所开发的策略在胃癌的早期诊断以及任何 miRNA 序列的临床监测方面具有巨大潜力。在实际样品分析中表现出色，无需任何预处理。因此，目前的研究表明，所开发的策略在胃癌的早期诊断以及任何 miRNA 序列的临床监测方面具有巨大潜力。