纸质空心金纳米笼SERS传感器的制备及对非小细胞肺癌患者痰液中miRNAs的快速高灵敏检测

利用油水界面自组装法获得了单层空心金纳米笼(HGNCs)阵列基底. 通过时域有限差分方法, 证明HGNCs间隙可提供大量“热点”, 从而使基底表现出优异的表面增强拉曼散射(SERS)性能. 同时, 将拉曼信号分子标记的发夹结构DNA与基底链接, 在与目标miRNAs互补杂交后进行SERS信号检测. 结果表明, 基于单层HGNCs阵列基底的SERS传感器具有优良的灵敏度、 可重复性和特异性, 对痰液中miR-196a和miR-21的检出限分别为10.00和36.15 amol/L. 为了验证该SERS传感器在临床检测中的准确性, 利用其对非小细胞肺癌(NSCLC)患者痰液中miR-196a和miR-21进行检测, 并将结果与实时定量多聚核苷酸链式反应技术(qRT-PCR)的检测结果进行了比较. 2种检测方法均显示NSCLC患者痰液中miR-196a和miR-21的表达高于健康人, 检测结果间没有统计学差异, 且相对标准偏差均低于10%. 因此, 纸质空心金纳米笼SERS传感器在NSCLC诊断中具有应用价值, 可能成为生物医学诊断领域miRNAs研究的一个替代工具.

Preparation of Paper Hollow Gold Nanocage SERS Sensor and Its Rapid and Highly Sensitive Detection for miRNAs in Sputum of Patients with Non-small Cell Lung Cancer

The abnormal expression of nucleic acid is closely related to the occurrence and development of tumor. Detecting the expression of micro-RNA（miRNAs） markers is of great significance for the diagnosis and treatment of non-small cell lung cancer（NSCLC）. In this work， the monolayer hollow gold nanocages（HGNCs） array substrate was fabricated by the self-assembly method at the oil-water interface. It was proved that the HGNCs gap provided a large number of “hot spots” by FDTD method， which made the substrate exhibit an excellent surface-enhanced Raman scattering（SERS） performance. At the same time， the hairpin DNA labeled by Raman signal molecule was linked with the substrate， and then the SERS signal was detected after complementary hybridization with the target miRNAs. The detection limits of miR-196a and miR-21 in sputum were 10.00 and 36.15 amol/L， respectively. In order to verify the accuracy of the sensor in clinical detection， the SERS sensor was used to detect miR-196a and miR-21 in sputum of patients with NSCLC， and the results were compared with those of real-time quantitative polynucleotide chain reaction technology. There were no significant differences between the results of the two detection methods， which both showed that the expressions of miR-196a and miR-21 in sputum of NSCLC patients were higher than those of healthy people， and the relative standard deviations were less than 10%. Therefore， the paper HGNCs SERS sensor has potential application in NSCLC diagnosis， and may become an alternative tool for miRNAs research in biomedical diagnosis field.