Department of Microelectronic Science and Engineering, School of Physical Science and Technology, Ningbo University, Ningbo 315211, Zhejiang, PR China.
GongQing Institute of Science and Technology, Gongqingcheng 332020, Jiangxi, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Oct 5;278:121304. doi: 10.1016/j.saa.2022.121304. Epub 2022 Apr 28.
Attributed to poor signal uniformity and external interference, ultrasensitive surface-enhanced Raman spectroscopy (SERS) still faces difficulties in the reliable and quantitative detection of trace molecules. Here, a facile Ag/Si/sodium carboxy methyl cellulose (NaCMC) film with internal standard (IS) was promoted for quantitative determination of thiram. The effects of preparation conditions on SERS activity of the film were systematically investigated and then a flexible SERS substrate with high sensitivity and uniformity was fabricated. The enhancement factor was calculated to be 1.12 × 10 and SERS mapping was recorded with a relative standard deviation value of 19.8% by utilizing 4-mercaptobenzoic acid (4-MBA) as target molecule. Additionally, the dominant contribution of the IS from encapsulated Si nanoparticles (NPs) was confirmed in the quantitative assay of 4-MBA and thiram, facilitating attractive fitting coefficients (R) as 0.991 and 0.998. Besides that, the proposed flexible film was conducted to scrub trace thiram from the surfaces of apple, orange, and cucumber, resulting in recoveries of 89%, 94%, and 91%. A smart and facile quantitative SERS substrate was developed here for monitoring trace biochemical molecules, verifying its potential utilizations in monitoring pesticide residues.
由于信号均匀性差和外部干扰，超灵敏表面增强拉曼光谱（SERS）在痕量分子的可靠和定量检测方面仍然存在困难。在这里，我们提出了一种简便的 Ag/Si/羧甲基纤维素钠（NaCMC）薄膜内标（IS），用于定量测定福美双。系统研究了制备条件对薄膜 SERS 活性的影响，然后制备了具有高灵敏度和均匀性的柔性 SERS 基底。利用 4-巯基苯甲酸（4-MBA）作为目标分子，计算得到的增强因子为 1.12×10，并且通过 SERS mapping 记录到的相对标准偏差值为 19.8%。此外，通过封装的 Si 纳米颗粒（NPs）内标，在定量测定 4-MBA 和福美双时，证实了其主要贡献，这使得拟合系数（R）分别达到了 0.991 和 0.998。此外，所提出的柔性薄膜还用于从苹果、橙子和黄瓜表面清洗痕量福美双，回收率分别为 89%、94%和 91%。这里开发了一种智能且简便的定量 SERS 基底，用于监测痕量生化分子，验证了其在监测农药残留方面的潜在应用。
