An ultrasensitive electrochemical genosensor has been fabricated for the double determination of two different specific sequences deduced from the maternally expressed gene3 (MEG3) lncRNA (long noncoding RNA), which was demonstrated by coupling RNase A-aided target recycling with DNA supersandwich-induced signal enhancement, based on a composite interface of graphene-like tungsten disulfide/dendritic gold nanostructures (WS₂/DGN). Firstly, duple target sequences of T₁ and T₂ were captured by the primer probes of P₁/P₂ functionalized Fe₃O₄@C magnetic nanoparticles, via the DNA/RNA hybridization between T₁/T₂ and P₁/P₂. In the presence of RNase A, T₁ and T₂ were released to trigger the target recycling, accompanied by the generation of numerous intermediate DNAs designated as IT₁ and IT₂, respectively. After the magnetic separation, the IT₁ and IT₂ were liberated and hybridized with the capture probes of CP₁/CP₂ loaded DGN/WS₂ modified electrode. Subsequently, the stepwise DNA hybridization chain reactions (HCR) labeled with ferrocene (Fc) and methyleneblue (MB) were processed, respectively. The DPV current values of Fc and MB were recorded, which were proportional with the concentration of T₁ and T₂, respectively. Using the multiple amplification strategy, this newly designed genosensor provided a wide linear range from 1 fM to 100 pM with a low detection limit of 0.25 fM for T₁ and 0.3 fM for T₂. The application of the genosensor in real serum sample has also been studied, confirming the excellent selectivity and sensitivity for the application in bioanalysis and clinical diagnostics.

已经制造了一种超灵敏的电化学基因传感器，用于双重测定从母体表达的gene3（MEG3）lncRNA（长非编码RNA）推导的两个不同的特定序列，这通过将RNase A辅助的靶标回收与DNA超三明治诱导的信号增强偶联来证明，基于类似石墨烯的二硫化钨/树突状金纳米结构（WS ₂ / DGN）的复合界面。首先，通过T ₁ / T ₂之间的DNA / RNA杂交，通过P ₁ / P ₂功能化的Fe ₃ O ₄ @C磁性纳米粒子的引物探针捕获T ₁和T _2的双重靶序列。和P ₁ / P ₂。在存在RNase A的情况下，T ₁和T ₂被释放以触发靶标回收，并伴随着大量中间DNA的产生，分别被命名为IT ₁和IT ₂。磁分离后，将IT ₁和IT ₂释放，并与装载CP ₁ / CP _2的DGN / WS ₂的捕获探针杂交修饰电极。随后，分别处理了用二茂铁（Fc）和亚甲基蓝（MB）标记的逐步DNA杂交链反应（HCR）。记录Fc和MB的DPV电流值，分别与T ₁和T ₂的浓度成比例。使用多重扩增策略，这种新设计的基因传感器提供了从1 fM到100 pM的宽线性范围，对T ₁和T _2的检测限较低，分别为0.25 fM和0.3 fM 。还对基因传感器在实际血清样品中的应用进行了研究，证实了其在生物分析和临床诊断中的优异选择性和敏感性。