Yuan Qi, Wang Yunqing, Mei Rongchao, Zhao Xizhen, Song Jie, Chen Jiadong, Wu Yixuan, Chen Lingxin
Shandong Key Laboratory of Coastal Environmental Processes, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003, P. R. China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Environ Sci Technol. 2025 Jun 24;59(24):12292-12301. doi: 10.1021/acs.est.5c03571. Epub 2025 Jun 12.
Identification and quantitative analysis of nanoplastics (NPs) in the environment are extremely challenging. Surface-enhanced Raman scattering (SERS) is a promising technique, but conventional solid SERS substrate-based detection faces difficulties such as ensuring NPs make contact with hotspots, dealing with uneven particle distribution, and poor detection repeatability. Herein, we propose a simple and sensitive SERS detection strategy by co-self-assembling silver (Ag) nanoparticles and NPs in a monolayer. 90% of NPs in solution spontaneously transfer to the monolayer within 30 s. More importantly, a single NP can be uniformly entrapped in Ag nanoparticle SERS "hotspots", resulting in a significant enhancement of the intrinsic Raman signal. This enhancement enables quantitative detection in the range of 10-2 mg/L for 80, 300, and 800 nm polystyrene (PS) NPs, with a low detection limit of 10 mg/L. The method allows for the identification of various plastic types, including PS, poly(methyl methacrylate) (PMMA), polyethylene terephthalate (PET), and polyformaldehyde (POM). This method was used to determine the efficacy of NP generation from bulk PS foam through physical (sand friction) and biological (mealworm ingestion) routes. Moreover, NPs in real seawater collected from a rocky beach were quantitatively analyzed. The coassembly monolayer-based SERS detection provides a straightforward and sensitive technique for identification and quantitative analysis of NPs.
环境中纳米塑料（NPs）的识别和定量分析极具挑战性。表面增强拉曼散射（SERS）是一种很有前景的技术，但基于传统固体SERS基底的检测面临着诸多困难，如确保纳米塑料与热点接触、处理颗粒分布不均以及检测重复性差等问题。在此，我们提出了一种简单且灵敏的SERS检测策略，通过在单层中共自组装银（Ag）纳米颗粒和纳米塑料。溶液中90%的纳米塑料在30秒内自发转移到单层中。更重要的是，单个纳米塑料可以均匀地捕获在Ag纳米颗粒SERS“热点”中，从而显著增强固有拉曼信号。这种增强使得能够对80、300和800纳米的聚苯乙烯（PS）纳米塑料在10 -2毫克/升范围内进行定量检测，检测下限低至10毫克/升。该方法能够识别包括PS、聚甲基丙烯酸甲酯（PMMA）、聚对苯二甲酸乙二酯（PET）和聚甲醛（POM）在内的各种塑料类型。此方法用于通过物理（砂摩擦）和生物（黄粉虫摄食）途径确定由块状PS泡沫产生纳米塑料的效率。此外，对从岩石海滩采集的实际海水中的纳米塑料进行了定量分析。基于共组装单层的SERS检测为纳米塑料的识别和定量分析提供了一种直接且灵敏的技术。
