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Minimizing transient microenvironment-associated variability for analysis of environmental anthropogenic contaminants via ambient ionization 通过原位质谱研究人源微生物与环境毒理

The rapid and quantitative analysis of anthropogenic contaminants in environmental matrices is crucial for regulatory testing and to elucidate the environmental fate of these pollutants. Direct ambient mass spectrometry (AMS) methodologies greatly increase sample throughput, can be adapted for onsite analysis and are often regarded as semi-quantitative by most developed protocols. One of the limitations of AMS, especially for on site analysis applications, is the irreproducibility of the measurements related to the occurrence of transient microenvironments (TME) and variable background interferences. In this work we report an effective strategy to minimize these effects by hyphenating, for the first time, solid phase microextraction (SPME) arrow to mass spectrometry via a thermal desorption unit (TDU) and direct analysis in real time (DART) source. The developed method was optimized for the extraction and analysis of pesticides and pharmaceuticals from surface water. It was demonstrated that the hyphenation of the SPME and TDU-DART resulted in reduced background contamination, indicating the suitability of the method for onsite analysis even in variable and non-ideal environments. Model analytes were quantitated in the low μg/L range with a total analysis time of less than 5 min, linear dynamic ranges (LDR) and interday reproducibility for most compounds being 2.5–500 μg/L and lower than 10%, respectively. The developed approach provides an excellent analytical tool that can be applied for the onsite high-throughput analysis of water samples as well as air and aereosols. Considering the tunability of our extraction process, time-resolved environmental monitoring can be achieved onsite within minutes. 环境基质中人为污染物的快速定量分析对于监管检测至关重要。原位质谱（AIMS）极大地提高了样品通量，适用于现场分析。对于现场分析应用，瞬态微环境（TME）和可变背景可能干扰重现性。在这项工作中，我们开发了一种有效的策略，将固相微萃取（SPME）与质谱联用，通过热解吸单元（TDU）和实时直接分析离子源（DART）来最小化这些影响。该方法适用于地表水中杀虫剂和药物的提取和分析。结果表明，SPME 和 TDU-DART 联用降低了背景污染，即使在可变和非理想环境中也能够进行现场分析。模型分析物在低浓度范围内定量，总分析时间小于5分钟，大多数化合物的线性动态范围（LDR）和日间现性分别为2.5-500μg/L和低于10％。该方法提供了一种优异的分析工具，用于水样以及空气和土壤的现场高通量分析，并且可在几分钟内实现现场环境监测。

274 2021-07-13

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