Detection of microplastics from water is crucial for various reasons, such as food safety monitoring, monitoring of the fate and transport of microplastics, and development of preventive measures for their occurrence. Currently, microplastics are detected by isolating them using filtration, separation by centrifugation, or membrane filtration, subsequently followed by analysis using well-established analytical methods, such as Raman spectroscopy. However, due to their variability in shape, color, size, and density, isolation using the conventional methods mentioned above is cumbersome and time-consuming. In this work, we show a surface-nanodroplet-decorated microfluidic device for isolation and analysis of small microplastics (diameter of 10 μm) from water. Surface nanodroplets are able to capture nearby microplastics as water flows through the microfluidic device. Using a model microplastic solution, we show that microplastics of various sizes and types can be captured and visualized by using optical and fluorescence microscopy. More importantly, as the surface nanodroplets are pinned on the microfluidic channel, the captured microplastics can also be analyzed using a Raman spectroscope, which enables both physical (i.e., size and shape) and chemical (i.e., type) characterization of microplastics at a single-particle level. The technique shown here can be used as a simple, fast, and economical detection method for small microplastics.

中文翻译：

---

使用表面纳米液滴对微塑料进行微流控检测和分析

出于多种原因，检测水中的微塑料至关重要，例如食品安全监测、监测微塑料的归宿和运输以及制定其发生的预防措施。目前，微塑料的检测方法是使用过滤、离心分离或膜过滤来分离微塑料，然后使用拉曼光谱等成熟的分析方法进行分析。然而，由于它们的形状、颜色、大小和密度各异，使用上述传统方法进行分离既麻烦又耗时。在这项工作中，我们展示了一种表面纳米液滴装饰的微流体装置，用于从水中分离和分析小型微塑料（直径为 10 μm）。当水流过微流体装置时，表面纳米液滴能够捕获附近的微塑料。使用模型微塑料解决方案，我们表明可以使用光学和荧光显微镜捕获和可视化各种尺寸和类型的微塑料。更重要的是，由于表面纳米液滴被固定在微流体通道上，捕获的微塑料也可以使用拉曼光谱仪进行分析，从而可以一次性对微塑料进行物理（即尺寸和形状）和化学（即类型）表征。 -颗粒水平。这里展示的技术可以用作小型微塑料的简单、快速且经济的检测方法。