Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications, Nanjing, China.
Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications, Nanjing, China; College of Geography and Biological Information, Nanjing University of Posts and Telecommunications, Nanjing, China.
Nanomedicine. 2018 Aug;14(6):1797-1807. doi: 10.1016/j.nano.2018.05.006. Epub 2018 May 16.
Identification of tumor-related mRNA in living cells hold great promise for early cancer diagnosis and pathological research. Herein, we present poly-adenine (polyA)-mediated fluorescent spherical nucleic acid (FSNA) probes for intracellular mRNA detection with regulable sensitivities by programmably adjusting the loading density of DNA on gold nano-interface. Gold nanoparticles (AuNPs) functionalized with polyA-tailed recognition sequences were hybridized to fluorescent "reporter" strands to fabricate fluorescence-quenched FSNA probes. While exposed to target gene, the "reporter" strands were released from FSNA through strand displacement and fluorescence was recovered. With polyA20 tail as the attaching block, the detection limit of FSNA probes was calculated to be 0.31 nM, which is ~55 fold lower than that of thiolated probes without surface density regulation. Quantitative intracellular mRNA detection and imaging could be achieved with polyA-mediated FSNA probes within 2 hours, indicating their application potential in rapid and sensitive intracellular target imaging.
在活细胞中鉴定肿瘤相关 mRNA 对癌症的早期诊断和病理研究具有重要意义。在此，我们提出了聚腺苷酸（polyA）介导的荧光球形核酸（FSNA）探针，通过程序控制 DNA 在金纳米界面上的加载密度，实现了可调节灵敏度的细胞内 mRNA 检测。用聚 A 尾识别序列功能化的金纳米粒子（AuNPs）与荧光“报告”链杂交，制备荧光猝灭的 FSNA 探针。当暴露于靶基因时，FSNA 通过链置换从 FSNA 中释放“报告”链，恢复荧光。以聚 A20 尾为附着块，FSNA 探针的检测限计算为 0.31 nM，比没有表面密度调节的巯基化探针低约 55 倍。聚 A 介导的 FSNA 探针可在 2 小时内实现定量的细胞内 mRNA 检测和成像，表明其在快速、灵敏的细胞内靶标成像中的应用潜力。
