Guo Xinyuan, Li Shu, Wang Tong, Su Jie, Liu Yadi, Chen Jing, Zhan Jinhua
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
J Hazard Mater. 2025 Aug 15;494:138488. doi: 10.1016/j.jhazmat.2025.138488. Epub 2025 May 3.
The issue of micro/nanoplastics has attracted widespread attention. The accurate quantitation of micro/nanoplastics remains challenging due to their heterogeneous size distributions. Herein, a systematic method was proposed that integrates Raman or surface-enhanced Raman spectroscopy (SERS) hyphenated to size-fractionated filtration (SFF-R/S) and a slope-matching strategy, thereby enhancing quantitative accuracy in spectral data acquisition and data handling. Micro/nanoplastics were categorized into four size fractions (>1 μm, 500 nm-1 μm, 50-500 nm, and <50 nm). Raman spectroscopy was employed to analyze larger particles, while SERS was used for 50-500 nm and sub-50 nm nanoplastics. In SFF-R/S, the spectral interferences between fractions were eliminated, thereby improving the accuracy of spectral intensities. In external quantitation, a slope-matching method was used to improve analytical accuracy by estimating particle size. The relative error was < 10 % for single fraction quantitation and < 5 % for mixtures. This systematic method works well with micro/nanoplastics of different polymers and showed a detection limit lowered to 2 × 10 g·L for polystyrene (PS) nanoplastics. Its practical utility was validated by the analysis of released micro/nanoplastics from disposable PS cups. This work provides information on chemical components, concentrations, and size distribution of micro/nanoplastics mixtures, which advances our understanding of their environmental behavior and physiological effects.
微塑料/纳米塑料问题已引起广泛关注。由于微塑料/纳米塑料尺寸分布不均一，其准确定量仍具有挑战性。在此，我们提出了一种系统方法，该方法将拉曼光谱或表面增强拉曼光谱（SERS）与尺寸分级过滤（SFF-R/S）以及斜率匹配策略相结合，从而提高光谱数据采集和数据处理中的定量准确性。微塑料/纳米塑料被分为四个尺寸级别（>1μm、500nm - 1μm、50 - 500nm和<50nm）。拉曼光谱用于分析较大颗粒，而SERS用于分析50 - 500nm和小于50nm的纳米塑料。在SFF-R/S中，各尺寸级别之间的光谱干扰被消除，从而提高了光谱强度的准确性。在外部定量中，采用斜率匹配方法通过估计颗粒尺寸来提高分析准确性。单一组分定量的相对误差<10%，混合物定量的相对误差<5%。这种系统方法对不同聚合物的微塑料/纳米塑料均有效，并且对于聚苯乙烯（PS）纳米塑料，其检测限降至2×10 g·L 。通过分析一次性PS杯释放的微塑料/纳米塑料，验证了该方法的实际应用价值。这项工作提供了有关微塑料/纳米塑料混合物化学成分、浓度和尺寸分布的信息，有助于我们进一步了解它们的环境行为和生理效应。
