Brunnbauer Lukas, Kronlachner Laura, Foisner Elias, Limbeck Andreas
TU Wien, Institute of Chemical Technologies and Analytics Getreidemarkt 9/164 1060 Vienna Austria
J Anal At Spectrom. 2025 Jan 27;40(3):753-761. doi: 10.1039/d4ja00351a. eCollection 2025 Mar 5.
The need to analyze and characterize microplastics (MPs) is ever-increasing to monitor and understand their environmental impact. In this work, a developed calibration approach that utilizes an in-house-created polystyrene (PS) thin film for the sizing of MPs is presented, circumventing the need for certified particulate standard material. LA was used for sampling and transporting intact MPs of different sizes and polymer types to the ICP-MS. For the calibration, defined amounts of carbon were introduced into the ICP-MS by quantitatively ablating a polymer thin film with different laser spot sizes. With this approach, a LOD of 4.85 pg carbon was obtained, which translates to a size of 2.12 μm for spheric PS particles. The calibration using PS thin film was successfully applied to sampled PS MPs and allowed accurate sizing of 2 μm, 3 μm, and 4.5 μm particles. When using the PS calibration for determining polyvinyl chloride (PVC) and poly(methyl methacrylate) (PMMA) particle sizes, a good estimate of the size could be achieved despite the different compositions of the polymers. This indicates the universal applicability of the presented approach. The investigation of the transport efficiency showed that it is mainly influenced by particle size, and factors such as the polymer type and length of the transport line and carrier gas. Under optimum conditions, up to 95% of the sampled particles were detected.
为监测和了解微塑料（MPs）对环境的影响，对其进行分析和表征的需求日益增加。在这项工作中，提出了一种利用自制聚苯乙烯（PS）薄膜对微塑料进行尺寸测量的校准方法，无需使用经过认证的颗粒标准物质。激光烧蚀（LA）用于将不同尺寸和聚合物类型的完整微塑料采样并传输至电感耦合等离子体质谱仪（ICP-MS）。在校准过程中，通过用不同激光光斑尺寸定量烧蚀聚合物薄膜，将规定量的碳引入ICP-MS。通过这种方法，获得了4.85 pg碳的检测限，对于球形PS颗粒，这相当于2.12μm的尺寸。使用PS薄膜进行的校准成功应用于采样的PS微塑料，并能准确测量2μm、3μm和4.5μm颗粒的尺寸。在使用PS校准来确定聚氯乙烯（PVC）和聚甲基丙烯酸甲酯（PMMA）颗粒尺寸时，尽管聚合物组成不同，但仍能对尺寸进行良好估计。这表明所提出方法具有普遍适用性。对传输效率的研究表明，它主要受颗粒尺寸以及聚合物类型、传输线长度和载气等因素影响。在最佳条件下，高达95%的采样颗粒被检测到。
