【摘要】 基于识别竞争策略和金十二面体(AuNDs)阵列，构建了表面增强拉曼光谱(SERS)传感器，并实现了健康人和结直肠癌(CRC)患者血清中两种miRNA的高效检测。通过将拉曼信号分子和适配体互补链修饰到金纳米双锥(AuNBP)表面，制备了两种标记探针，并将其结合在适配体功能化AuNDs阵列上构建SERS传感器。目标miRNAs能够特异性结合适配体，使标记探针从AuNDs阵列表面竞争性脱落，进而使得SERS信号降低。该方法对血清中miR-21和miR-92a的检出限分别低至5.7 pmol/L和8.4 pmol/L，反应时间仅需6 min。临床检测结果显示，相对于健康人，CRC患者血清中miR-21和miR-92a的表达水平显著升高。SERS结果与实时定量聚合酶链反应(qRT-PCR)一致，证实了其准确性。该方法为miRNA的快速、高灵敏、同时检测提供了新的策略，在CRC的早期诊断中具有巨大的临床潜在价值。更多还原

【Abstract】 Based on the recognition competition strategy and Au nano dodecahedron(AuNDs) arrays,a surface-enhanced Raman scattering(SERS) sensor was constructed to efficiently detect two miRNAs in the serum of healthy individuals and colorectal cancer(CRC) patients. Two kinds of labeled probes were prepared by modifying Raman signaling molecules and complementary chains of aptamers onto the surface of Au nano bipyramids(AuNBP),which were combined on the aptamer-functionalized AuNDs arrays for the construction of the SERS sensor. The target miRNAs were able to specifically bind the aptamers,resulting in competitive detachment of the labeled probes from the surface of the AuNDs arrays and reduced SERS signals. Using this method, the detection limits of miR-21 and miR-92a in serum were as low as 5. 7 pmol/L and 8. 4 pmol/L,respectively,and the reaction incubation time was only 6 min. Clinical assays showed that the expression levels of miR-21 and miR-92a in the serum of CRC patients were significantly elevated relative to those of healthy individuals.The SERS results of this protocol were consistent with real-time quantitative polymerase chain reaction(qRT-PCR),confirming its accuracy. This protocol provides a new strategy for rapid,highly sensitive,and simultaneous detection of miRNAs,which has great potential clinical value for early diagnosis of CRC.更多还原