This work is focused on the development of a genosensor for microRNA-21 quantification using surface plasmon resonance (SPR) to transduce the hybridization event. The biosensing platform was built by self-assembling two bilayers of poly(diallyldimethylammonium chloride) (PDDA) and graphene oxide (GO) at a gold surface modified with 3-mercaptopropane sulfonate (MPS), followed by the covalent attachment of the DNA probe. GO was used in two directions, to allow the anchoring of the probe DNA and to increase the sensitivity of the biosensing event due to its field enhancer effect. The new bioanalytical platform represents an interesting alternative for the label-free biosensing of microRNA-21, with a linear range between 1.0 fM and 10 nM, a sensitivity of 5.1 ± 0.1 moM-1 and a detection limit of 0.3fM. The proposed sensing strategy was successfully used for the quantification of microRNA-21 in enriched urine samples. Graphical abstract.

中文翻译：

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基于无标记氧化石墨烯的 SPR 基因传感器，用于定量 microRNA21。

这项工作的重点是开发用于 microRNA-21 量化的基因传感器，使用表面等离子共振 (SPR) 来转导杂交事件。该生物传感平台是通过在用 3-巯基丙烷磺酸盐 (MPS) 修饰的金表面上自组装聚二烯丙基二甲基氯化铵 (PDDA) 和氧化石墨烯 (GO) 的两个双层构建的，然后共价连接 DNA 探针。GO 用于两个方向，以允许探针 DNA 的锚定，并由于其场增强效应而增加生物传感事件的灵敏度。新的生物分析平台代表了 microRNA-21 的无标记生物传感的有趣替代方案，其线性范围在 1.0 fM 和 10 nM 之间，灵敏度为 5.1 ± 0.1 moM-1，检测限为 0.3fM。所提出的传感策略成功地用于定量富集尿液样本中的 microRNA-21。图形概要。