Qi Qi, Liu Chunhui, Liu Lintao, Meng Qingyi, Wei Shuhua, Ming Anjie, Zhang Jing, Wang Yanrong, Wu Lidong, Zhu Xiaoli, Wei Feng, Yan Jiang
School of Information science and technology, North China University of Technology, No. 5 Jinyuanzhuang Street, Shijingshan District, Beijing 100144, China.
State Key Laboratory of Advanced Materials for Smart Sensing, General Research Institute for Nonferrous Metals, No. 11 Xingkedong Street, Huairou District, Beijing 101402, China.
Micromachines (Basel). 2019 Apr 27;10(5):282. doi: 10.3390/mi10050282.
Surface-enhanced Raman spectroscopy (SERS) substrates with high sensitivity and reproducibility are highly desirable for high precision and even molecular-level detection applications. Here, large-scale uniformly hybrid nanoparticle-enhanced Raman spectroscopy (NERS) substrates with high reproducibility and controllability were developed. Using oxygen plasma treatment, large-area and uniformly rough polystyrene sphere (URPS) arrays in conjunction with 20 nm Au films (AuURPS) were fabricated for SERS substrates. Au nanoparticles and clusters covered the surface of the URPS arrays, and this increased the Raman signal. In the detection of malachite green (MG), the fabricated NERS substrates have high reproducibility and sensitivity. The enhancement factor (EF) of Au nanoparticles and clusters was simulated by finite-difference time-domain (FDTD) simulations and the EF was more than 10. The measured EF of our developed substrate was more than 10 with a relative standard deviation as low as 6.64%-13.84% over 15 points on the substrate. The minimum limit for the MG molecules reached 50 ng/mL. Moreover, the Raman signal had a good linear relationship with the logarithmic concentration of MG, as it ranged from 50 ng/mL to 5 μg/mL. The NERS substrates proposed in this work may serve as a promising detection scheme in chemical and biological fields.
具有高灵敏度和可重复性的表面增强拉曼光谱（SERS）基底对于高精度甚至分子水平的检测应用来说是非常需要的。在此，开发了具有高可重复性和可控性的大规模均匀混合纳米颗粒增强拉曼光谱（NERS）基底。通过氧等离子体处理，制备了大面积且均匀粗糙的聚苯乙烯球体（URPS）阵列与20 nm金膜（AuURPS）结合的SERS基底。金纳米颗粒和团簇覆盖在URPS阵列表面，这增强了拉曼信号。在孔雀石绿（MG）的检测中，所制备的NERS基底具有高可重复性和灵敏度。通过时域有限差分（FDTD）模拟对金纳米颗粒和团簇的增强因子（EF）进行了模拟，其EF大于10。我们所开发基底的实测EF大于10，在基底上的15个点上相对标准偏差低至6.64% - 13.84%。MG分子的最低检测限达到50 ng/mL。此外，当MG浓度范围为50 ng/mL至5 μg/mL时，拉曼信号与MG的对数浓度具有良好的线性关系。本文提出的NERS基底可能成为化学和生物领域一种有前景的检测方案。
