Zhang Rui, Lai Yongchao, Zhan Jinhua
Key Laboratory for Colloid & Interface Chemistry of Education Ministry, Department of Chemistry, Shandong University, Jinan 250100, China.
Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan 250062, China.
Nanomaterials (Basel). 2021 Mar 9;11(3):672. doi: 10.3390/nano11030672.
The development of high-quality flexible surface-enhanced Raman spectroscopy (SERS) substrates is crucial for developing rapid SERS analysis in situ. Silver nanowire membranes as novel flexible substrates could benefit from the high collection efficiency of analytes by wrapping complex surfaces or wiping the surfaces of samples. However, their low SERS performance impedes further applications of silver nanowire membranes in analyte detection. Herein, we report an ultra-high-sensitivity silver nanowire membrane synthesized by a simple and time-saving cyclic voltammetry (CV) method. After CV treatment, a part of the silver nanowires on the silver nanowire membrane turned into small nanoparticles and nanorods. This nanostructure's reconstitution increased the analytical enhancement factor of silver nanowire membranes by 14.4 times. Scanning and transmission electron microscopy, UV-vis spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were employed to investigate the transformation in the membrane nanostructure. The CV-treated substrates exhibited high surface-enhanced Raman activity and good temporal stability. The limits of detection (LODs) for -aminothiophenol, crystal violet, tetramethylthiuram disulfide, sodium perchlorate, malachite green, fluoranthene, and potassium nitrate are 3.7 × 10 M, 5.1 × 10 M, 5.4 × 10 M, 6.3 × 10 M, 0.00693 ng, 0.0810 ng, and 0.0273 ng on this substrate, respectively. Additionally, the developed substrate is feasible for the detection of crystal violet in real samples. These results certify that CV-treated substrates possess broad application prospects in on-site SERS analysis.
高质量柔性表面增强拉曼光谱（SERS）基底的开发对于原位快速SERS分析的发展至关重要。银纳米线膜作为新型柔性基底，通过包裹复杂表面或擦拭样品表面，可受益于对分析物的高收集效率。然而，它们较低的SERS性能阻碍了银纳米线膜在分析物检测中的进一步应用。在此，我们报道了一种通过简单且省时的循环伏安法（CV）合成的超高灵敏度银纳米线膜。经过CV处理后，银纳米线膜上的一部分银纳米线转变为小纳米颗粒和纳米棒。这种纳米结构的重构使银纳米线膜的分析增强因子提高了14.4倍。采用扫描和透射电子显微镜、紫外可见光谱、X射线衍射和X射线光电子能谱来研究膜纳米结构的转变。经CV处理的基底表现出高表面增强拉曼活性和良好的时间稳定性。在该基底上，对氨基硫酚、结晶紫、二硫化四甲基秋兰姆、高氯酸钠、孔雀石绿、荧蒽和硝酸钾的检测限分别为3.7×10⁻⁸ M、5.1×10⁻⁸ M、5.4×10⁻⁸ M、6.3×10⁻⁸ M、0.00693 ng、0.0810 ng和0.0273 ng。此外，所开发的基底对于实际样品中结晶紫的检测是可行的。这些结果证明经CV处理的基底在现场SERS分析中具有广阔的应用前景。
