Beijing Engineering Research Center of Optoelectronic Information and Instruments , Beijing Information Science and Technology University , Beijing 100016 , China.
School of Information and Communication Engineering , University of Electronic Science and Technology of China , Chengdu 611731 , China.
Anal Chem. 2019 Jan 2;91(1):1064-1070. doi: 10.1021/acs.analchem.8b04441. Epub 2018 Dec 18.
With the advanced development of miniaturized Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS) has extended its applications into the field of point-of-care testing (POCT) and demonstrated its great significance by virtue of its noninvasive property and capability of fingerprint identification. In the SERS-based analysis and/or sensing system, the preparation of a low-cost, high-performance SERS substrate is critically important. In this manuscript, vacuum filtration is utilized to fabricate the silver nanoparticles (AgNPs)-embedded nylon filter membrane (ANFM) as flexible paper-based SERS chips. By characterizing the typical analytes with a miniaturized smartphone-based Raman analyzer, the proposed SERS chips have successfully demonstrated good sensitivity, repeatability, and stability. The lowest concentration as detected can approach 1 pmol for rhodamine 6G (RH6G) and 10 pmol for both crystal violet (CV) and malachite green (MG), respectively. With the help of the microporous structure of the membrane, the ANFM-based SERS chips can implement the separation of small molecules from a complex mixture and can achieve "purified" SERS signals of targeted molecules. Besides, with the function of antifriction resistance and flexibility, the ANFM can serve as SERS papers to preconcentrate the contaminates by multiple swapping and further enhance the SERS signals for point-of-care analysis. Therefore, we demonstrate multifunctions of the flexible ANFM-based SERS chips, which provide a promising solution for the POCT analysis with the SERS technique on account of their flexibility and low fabrication cost.
随着微型拉曼光谱学的先进发展，表面增强拉曼光谱（SERS）已经将其应用扩展到即时检测（POCT）领域，并凭借其非侵入性和指纹识别能力显示出其重要意义。在基于 SERS 的分析和/或传感系统中，制备低成本、高性能的 SERS 基底至关重要。在本手稿中，利用真空过滤来制备银纳米颗粒（AgNPs）嵌入的尼龙滤膜（ANFM）作为柔性纸质 SERS 芯片。通过使用小型智能手机拉曼分析仪对典型分析物进行表征，所提出的 SERS 芯片成功地展示了良好的灵敏度、重复性和稳定性。对于罗丹明 6G（RH6G），可检测到的最低浓度可接近 1pmol，对于结晶紫（CV）和孔雀石绿（MG），则分别可达到 10pmol。借助膜的微孔结构，基于 ANFM 的 SERS 芯片可以实现小分子从复杂混合物中的分离，并实现目标分子的“纯化”SERS 信号。此外，ANFM 具有抗摩擦阻力和柔韧性，可以用作 SERS 纸，通过多次交换来浓缩污染物，并进一步增强用于即时检测分析的 SERS 信号。因此，我们展示了基于柔性 ANFM 的 SERS 芯片的多功能性，由于其灵活性和低成本制造，为 SERS 技术在 POCT 分析中提供了一种有前途的解决方案。
