Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, PR China.
Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, PR China; Institute of Biomedical Sciences, Zhongshan Hospital Fudan University, Shanghai, 200032, PR China.
Biosens Bioelectron. 2020 May 15;156:112130. doi: 10.1016/j.bios.2020.112130. Epub 2020 Mar 3.
Quantitative analysis is critical for biological and chemical sensing applications, yet still remains a great challenge in surface-enhanced Raman spectroscopy (SERS). Here we report the development of a novel fractal SERS nanoprobe with robust internal calibration standard and high multiplexing capability for ultrasensitive detection of DNA and microRNA. This fractal SERS nanoprobe consists of a solid Au core of ~13 nm, an inner hollow gap of ~1 nm, and a stellate outer shell. The inner hollow gap enables the embedding of Raman tags that can serve as a self-calibrating internal standard to effectively correct the fluctuations of samples and measuring conditions. The outer shell morphology is highly tunable, which provides distinct SERS enhancement and enables a reproducible quantitative measurement of nucleic acids down to femtomolar level. In addition, the flexibility of encoding crosstalk-free Raman tag molecules makes such SERS sensor particularly attractive for multiplexed bioassays. This technique is simple, reliable, and of wide applicability to various genomic screening and diagnostic applications.
定量分析对于生物和化学传感应用至关重要，但在表面增强拉曼光谱（SERS）中仍然是一个巨大的挑战。在这里，我们报告了一种新型分形 SERS 纳米探针的开发，该探针具有稳健的内部校准标准和高多重检测能力，可用于超灵敏检测 DNA 和 microRNA。这种分形 SERS 纳米探针由约 13nm 的实心 Au 核、约 1nm 的内部中空间隙和星状外壳组成。内部中空间隙能够嵌入拉曼标记物，用作自校准内部标准，有效地校正样品和测量条件的波动。外壳形态高度可调，可提供明显的 SERS 增强，并实现对核酸的可重复定量测量，低至飞摩尔水平。此外，编码无串扰拉曼标记分子的灵活性使这种 SERS 传感器特别适用于多重生物分析。该技术简单、可靠，广泛适用于各种基因组筛选和诊断应用。
