Ning Lichun, Li Junbo, Xie Qinhui, Hu Jianing, Liu Jian, Xu Cheng, Peng Jinsong, Chen Chunxia, Ji Wei
Center for Innovative Research in Synthetic Chemistry and Resource Utilization, College of Chemistry, Chemical Engineering and Resource Utilization, Northeast Forestry University, Harbin 150040, China.
Anal Chem. 2024 Nov 26;96(47):18772-18780. doi: 10.1021/acs.analchem.4c04153. Epub 2024 Oct 8.
A novel and simple coacervate microdroplet-based detection platform for the quantification of trace hydrophobic analytes is presented. Herein, taking advantage of the effective encapsulation and enrichment performance of the condensed coacervates, plasmonic metallic silver nanoparticles (AgNPs) and target hydrophobic analytes are simultaneously concentrated into a single microdroplet. The coencapsulation of AgNPs within coacervates promotes the formation of aggregates with a lot of "hot spots" for surface-enhanced Raman scattering (SERS) enhancement, facilitating the sensitive analysis of hydrophobic analytes by SERS technology. Such plasmonic coacervates are easily prepared and exhibit good reproducibility and signal uniformity. Optimized SERS performance by modulating the volume of encapsulated AgNPs enables quantitative determination of hydrophobic analytes of Nile Red, chlorpyrifos, benzo[e]pyrene, 20 and 50 nm polystyrene nanoplastics with low detection limits of 10 M, 10 M, 10 M, 0.05 ppb, and 0.5 ppb, and an approximately linear correlation between SERS signals and the analytical concentrations. This study opens a new convenient SERS platform for the ultrasensitive detection of hydrophobic hazardous substances, potentially becoming a rapid analysis method for extensive applications ranging from food safety to environment monitoring.
本文提出了一种新颖且简单的基于凝聚微滴的检测平台，用于定量分析痕量疏水性分析物。在此，利用凝聚凝聚层的有效包封和富集性能，将等离子体金属银纳米颗粒（AgNPs）和目标疏水性分析物同时浓缩到单个微滴中。AgNPs在凝聚层中的共包封促进了具有大量用于表面增强拉曼散射（SERS）增强的“热点”的聚集体的形成，便于通过SERS技术对疏水性分析物进行灵敏分析。这种等离子体凝聚层易于制备，具有良好的重现性和信号均匀性。通过调节包封的AgNPs的体积优化SERS性能，能够定量测定尼罗红、毒死蜱、苯并[e]芘、20和50纳米聚苯乙烯纳米塑料等疏水性分析物，检测限低至10 M、10 M、10 M、0.05 ppb和0.5 ppb，并且SERS信号与分析浓度之间具有近似线性相关性。本研究为超灵敏检测疏水性有害物质开辟了一个新的便捷SERS平台，有望成为从食品安全到环境监测等广泛应用的快速分析方法。
