Abstract:
Increasing demand for size-resolved identification and quantification of microplastic particles in drinking water and environmental samples requires the adequate validation of methods and techniques that can be used for this purpose. In turn, the feasibility of such validation depends on the existence of suitable certified reference materials (CRM). A new candidate reference material (RM), consisting of polyethylene terephthalate (PET) particles and a water matrix, has been developed. Here, we examine its suitability with respect to a homogeneous and stable microplastic particle number concentration across its individual units. A measurement series employing tailor-made software for automated counting and analysis of particles (TUM-ParticleTyper 2) coupled with Raman microspectroscopy showed evidence of the candidate RM homogeneity with a relative standard deviation of 12% of PET particle counts involving particle sizes >30 µm. Both the total particle count and the respective sums within distinct size classes were comparable in all selected candidate RM units. We demonstrate the feasibility of production of a reference material that is sufficiently homogeneous and stable with respect to the particle number concentration.
摘要:
对饮用水和环境样品中微塑料颗粒的尺寸分辨识别和定量的需求不断增加,需要对可用于此目的的方法和技术进行充分验证。反过来,这种验证的可行性取决于是否存在合适的认证参考材料(CRM)。新的候选参考材料(RM),由聚对苯二甲酸乙二醇酯(PET)颗粒和水基质组成,已经开发了。这里,我们检查了其在各个单位中均匀和稳定的微塑料颗粒数浓度方面的适用性。采用定制软件进行颗粒自动计数和分析的测量系列(TUM-ParticleTyper2)与拉曼显微光谱法相结合,显示了候选RM均一性的证据,其中PET颗粒计数的相对标准偏差为12%,涉及粒径>30μm。在所有选择的候选RM单位中,不同尺寸类别内的总颗粒计数和各自的总和都是可比的。我们证明了生产相对于颗粒数浓度足够均匀且稳定的参考材料的可行性。