面向医学单分子诊断的卷曲复合贵金属微纳米管研究

Surface-enhanced Raman scattering (SERS) is recognized as one of the most sensitive spectroscopic tools offering highly sensitive chemical and biological detection such as DNA and protein down to the single molecular level possible. The fact that particle plasmons allow the direct coupling of light to resonant electron plasmon oscillations has spurred tremendous research activities in the design and fabrication of highly SERS-active substrates in metallic nanostructures. Urgent bottleneck problems that should be solved now are: (1) It is still difficult to obtain complex metallic nanostructures with precision fabrication, so that the research and application of SERS is not easy; (2) The poor control over the size and shape of the metallic nanostructures allows one difficulty to observe homogeneously broadened line shapes of plasmon modes and gives rise to tunable absorption from the visible to near-IR region. Thus this project is aiming at fabricating a series of rolled-up noble metal composite micro/nano tubes, investigating the effects of the structure, diameter, and the structure aspect ratio, etc., of the tubes on the SERS efficiency and optimizing the sensor design from these findings, understanding the physical and chemical origins of the sensing capability. It should also be mentioned that rolled-up nanotech profits from all advantages of MEMS/NEMS technology. Furthermore, the specific tubular structures can integrate new and possibly more functions into one single device than flat thin films from optofluidic technology for single-molecule diagnosis.

表面增强拉曼散射（SERS）光谱是一种用于探测和鉴定各种分子的有力而灵敏的分析工具，其应用于生物分子如DNA序列、蛋白质和其他生物活性小分子的快速单分子检测和鉴定有极其重大的意义。国内外SERS活性基底的研究一直是金属材料的制备科学与跨学科应用的研究热点之一，目前亟待解决的"瓶颈"问题是：I金属纳米结构的精确制造有一定难度，从而使得SERS的研究及其应用变得困难；II利用金属介质上特定形状、尺寸的金属纳米结构来精确控制表面等离激元的共振频率，将光谱应用范围从可见调谐至生物传感领域尤为重要的近红外还远没有实现。因此本项目主要从实验和理论两方面入手，构筑一系列具有典型特征的复合贵金属微纳米管材料，调控金属管的几何尺寸、卷曲层数及材料组份，通过精确地制造复合贵金属微纳米管结构来控制表面等离激元共振频率，探索金属管微结构对于拉曼增强的理论本源，最终作为微流控光学芯片全分析系统用于医学单分子诊断。

本项目围绕卷曲复合贵金属微纳米管的设计、制造及作为微流控光学芯片全分析系统用于医学单分子诊断应用，开展了深入而系统的研究，取得了一系列重要的创新性成果，圆满完成了研究计划任务和预期目标。共完成SCI收录学术论文18篇，标志性的成果发表在Mater. Sci. Eng. R.、Nanoscale、J. Phys. Chem. C等一流杂志上（其中影响因子3.0以上的11篇）。在卷曲复合贵金属微纳米管制造方面，我们获得微纳米管精准制造的重要工艺参数及其控制技术，构筑了一系列具有典型特征的复合贵金属微纳米管材料；其后在物理上成功揭示了复合贵金属微纳米管表面等离激元的产生过程；最终获得复合贵金属微纳米管作为微流控光学芯片全分析系统用于医学单分子诊断的技术方案。