摘要

微塑料污染已成为一个全球性的环境问题，引起了人们的极大关注。为了评估微塑料的生物效应，需要准确地量化生物体中的微塑料。使用荧光强度定量生物体中的微塑料是常见的;生物样品的消化是一种重要的预处理方法。然而，微塑料可能被消化破坏，这会影响微塑料的荧光强度并导致测量值和真实值之间的大的偏差。在该研究中，研究了六种常用的消化剂：KOH，NaOH，H 2 O 2，HNO 3，HNO 3：HCl和HNO 3：HClO 4。研究了不同消解方法对微塑料荧光强度和表面形貌的影响，选择了最合适的方案。结果表明，在6种不同的消解方法中，KOH消解（100 g·L-1,60℃）对微塑料的荧光强度影响最小，不影响其表面形貌。其他五种消化方法导致微塑料的荧光强度的不同程度的降低并且损坏微塑料的表面（聚集，气泡，划痕和凹陷）。此外，KOH消化方法用于从生物样品中提取微塑料。回收率≥96.3％±0.5％，表明KOH消化方法适用于生物样品中的荧光微塑料。

Microplastic pollution has become a global environmental problem and is a cause of great concern. To evaluate the biological effects of microplastics, microplastics in organisms need to be accurately quantified. The quantification of microplastics in organisms using the fluorescence intensity is common; the digestion of biological samples is an important pretreatment method. However, the microplastics may be destroyed by digestion, which affects the fluorescence intensity of the microplastics and results in large deviations between measured and true values. In this study, six commonly used digestive agents were studied:KOH, NaOH, H2O2, HNO3, HNO3:HCl, and HNO3:HClO4. The effect of different digestion methods on the fluorescence intensity and surface morphology of microplastics was studied and the most suitable protocol was selected. The results show that, among the six different digestion methods, KOH digestion (100 g·L-1, 60℃) has the least influence on the fluorescence intensity of the microplastics and does not affect their surface morphology. The other five digestion methods lead to different degrees of reduction of the fluorescence intensity of microplastics and damage the microplastics' surface (aggregation, bubbles, scratches, and depressions). In addition, the KOH digestion method was used to extract microplastics from biological samples. The recovery rate was ≥ 96.3%±0.5%, indicating that the KOH digestion method is suitable for fluorescent microplastics in biological samples.

https://www.ncbi.nlm.nih.gov/pubmed/30628310