Wang Kaiqiang, Sun Da-Wen, Pu Hongbin, Wei Qingyi, Huang Lunjie
School of Food Science and Engineering , South China University of Technology , Guangzhou 510641 , China.
Food Refrigeration and Computerized Food Technology (FRCFT), Agriculture and Food Science Centre , University College Dublin , National University of Ireland, Belfield D04 V1W8 , Dublin 4, Ireland.
ACS Appl Mater Interfaces. 2019 Aug 14;11(32):29177-29186. doi: 10.1021/acsami.9b09746. Epub 2019 Aug 2.
The high sensitivity and long-term storage stability of a plasmonic substrate are vital for practical applications of the surface-enhanced Raman scattering (SERS) technique in real-world analysis. In this study, a rationally designed, ternary film-packaged, silver-coated gold-nanoparticle (Au@Ag NP) plasmonic array was fabricated and applied as a stable and high-performance SERS chip for highly sensitive sensing of thiabendazole (TBZ) residues in fruit juices. The ternary films played different roles in the plasmonic chip: a newborn poly(methyl methacrylate) (PMMA) film serving as a template for fixing the self-assembled closely packed monolayer Au@Ag NP array that provided an intensive hot spot, a fluorescent quantitative polymerase chain reaction adhesive film (qPCR film) acting as a carrier to retrieve the Au@Ag/PMMA film that was used to improve the robustness of the plasmonic array, and a polyethylene terephthalate (PET) film covered over the Au@Ag/PMMA/qPCR film performing as a barrier to improve the stability of the chip. The Au@Ag/PMMA/qPCR-PET film chip showed high sensitivity with an enhancement factor of 3.14 × 10, long-term storage stability without changing SERS signals for more than 2 months at room temperatures, and a low limit of detection for sensing TBZ in pear juice (21 ppb), orange juice (43 ppb), and grape juice (69 ppb). In addition, the procedure for fabricating the Au@Ag/PMMA/qPCR-PET film SERS chip was easy to handle, offering a new strategy to develop flexible and wearable sensors for on-site monitoring of chemical contaminants with a portable Raman spectrometer in the future.
等离子体基底的高灵敏度和长期存储稳定性对于表面增强拉曼散射（SERS）技术在实际分析中的实际应用至关重要。在本研究中，制备了一种经过合理设计的、三元膜封装的、涂银金纳米粒子（Au@Ag NP）等离子体阵列，并将其用作稳定且高性能的SERS芯片，用于高灵敏度检测果汁中的噻菌灵（TBZ）残留。三元膜在等离子体芯片中发挥了不同作用：新生的聚甲基丙烯酸甲酯（PMMA）膜用作固定自组装紧密堆积单层Au@Ag NP阵列的模板，该阵列提供了密集的热点；荧光定量聚合酶链反应粘附膜（qPCR膜）作为载体来回收Au@Ag/PMMA膜，用于提高等离子体阵列的稳健性；聚对苯二甲酸乙二醇酯（PET）膜覆盖在Au@Ag/PMMA/qPCR膜上，起到屏障作用以提高芯片的稳定性。Au@Ag/PMMA/qPCR - PET膜芯片显示出高灵敏度，增强因子为3.14×10，在室温下长期存储稳定性良好，超过2个月SERS信号不变，并且对梨汁（21 ppb）、橙汁（43 ppb）和葡萄汁（69 ppb）中TBZ的检测限较低。此外，制备Au@Ag/PMMA/qPCR - PET膜SERS芯片的过程易于操作，为未来使用便携式拉曼光谱仪开发用于现场监测化学污染物的柔性可穿戴传感器提供了一种新策略。
