6种消解方法对荧光测定生物体内聚苯乙烯微塑料的影响  

Influence of Six Digestion Methods on the Determination of Polystyrene Microplastics in Organisms Using the Fluorescence Intensity

作　　者：邹亚丹 徐擎擎 张哿 李富云 李锋民[1] ZOU Ya-dan;XU Qing-qing;ZHANG Ge;LI Fu-yun;LI Feng-min(Key Laboratory of Marine Environment and Ecology,Ministry of Education,Institute of Coastal Environmental Pollution Control,Ocean University of China,Qingdao 266100,China)

机构地区：[1]中国海洋大学环境科学与工程学院近海环境污染控制研究所海洋生态与环境教育部重点实验室,青岛266100

出　　处：《环境科学》2019年第1期496-503,共8页Environmental Science

基　　金：国家自然科学基金项目(51378480);国家自然科学基金委员会-山东省联合资助海洋科学研究中心项目(U1406403);国家重点基础研究发展规划(973)项目(2015CB453301)

摘　　要：微塑料污染已经成为全球性的环境问题,引起了人们的广泛关注,为了评估微塑料的生物效应,对生物体内微塑料进行准确定量成为了亟待解决的问题.在已有的微塑料研究中,利用荧光强度进行生物体内微塑料定量是较为常用的方法,而对生物样品进行消解则是重要的前处理方法.然而,消解可能会对微塑料产生破坏,影响微塑料的荧光强度,导致微塑料浓度的测定值与真实值存在巨大偏差.目前关于消解对微塑料荧光强度影响的研究比较匮乏,而荧光强度直接影响微塑料定量结果的准确性.因此本文研究了文献中常用的6种消解剂,分别为KOH、NaOH、H_2O_2、HNO_3、HNO_3∶HCl和HNO_3∶HClO_4,探究了不同消解方法对微塑料荧光强度和表面形态的影响,并选出最合适的微塑料消解方法.结果表明在6种不同消解方法中,KOH消解法(100 g·L^(-1),60℃)对微塑料的荧光强度影响最小,且对微塑料的表面形态没有明显影响.而另外5种消解法都不同程度地降低了微塑料的荧光强度,并造成了微塑料表面损伤,主要包括团聚、气泡、轻划痕以及深凹陷等.此外,利用KOH消解法对生物样品中的微塑料进行提取效率评估,回收率高达96.3%±0.5%,表明KOH消解法是一种合适的生物样品中荧光微塑料的提取方法.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.

关 键 词：微塑料 定量 消解 荧光强度 生物样品 

分 类 号：X830.2[环境科学与工程—环境工程]