Anal Chem. 2010 Dec 1;82(23):9626-30. doi: 10.1021/ac102475k. Epub 2010 Nov 8.
A novel, ultra low-cost surface enhanced Raman spectroscopy (SERS) substrate has been developed by modifying the surface chemistry of cellulose paper and patterning nanoparticle arrays, all with a consumer inkjet printer. Micro/nanofabrication of SERS substrates for on-chip chemical and biomolecular analysis has been under intense investigation. However, the high cost of producing these substrates and the limited shelf life severely limit their use, especially for routine laboratory analysis and for point-of-sample analysis in the field. Paper-based microfluidic biosensing systems have shown great potential as low-cost disposable analysis tools. In this work, this concept is extended to SERS-based detection. Using an inexpensive consumer inkjet printer, cellulose paper substrates are modified to be hydrophobic in the sensing regions. Synthesized silver nanoparticles are printed onto this hydrophobic paper substrate with microscale precision to form sensing arrays. The hydrophobic surface prevents the aqueous sample from spreading throughout the paper and thus concentrates the analyte within the sensing region. A SERS fingerprint signal for Rhodamine 6G dye was observed for samples with as low as 10 femtomoles of analyte in a total sample volume of 1 μL. This extraordinarily simple technique can be used to construct SERS microarrays immediately before sample analysis, enabling ultra low-cost chemical and biomolecular detection in the lab as well as in the field at the point of sample collection.
一种新颖的、超低成本的表面增强拉曼光谱（SERS）基底，通过修饰纤维素纸的表面化学性质和图案化纳米粒子阵列而开发出来，所有这些都可以使用消费者喷墨打印机完成。用于片上化学和生物分子分析的 SERS 基底的微纳制造一直是研究的热点。然而，这些基底的制造成本高，保质期有限，严重限制了它们的使用，特别是对于常规实验室分析和现场样本分析。基于纸张的微流控生物传感系统作为低成本一次性分析工具显示出巨大的潜力。在这项工作中，这个概念被扩展到基于 SERS 的检测中。使用廉价的消费者喷墨打印机，纤维素纸基底被修饰为在感测区域具有疏水性。将合成的银纳米粒子以微尺度精度打印到这种疏水性纸基底上，形成感测阵列。对于总样品体积为 1 μL 的样品，即使其中的分析物低至 10 飞摩尔，也可以观察到 Rhodamine 6G 染料的 SERS 指纹信号。这种非常简单的技术可以在样品分析之前立即构建 SERS 微阵列，从而能够在实验室以及在现场样本采集点进行超低成本的化学和生物分子检测。
