挥发性有机化合物的稳定性在热溶解管和溶液中
Kristian J Kiland1, Lucas Martins1, Scott A Borden1
1Integrative Oncology, British Columbia Cancer Research Institute, Vancouver, British Columbia, Canada.
Journal of breath research
|December 17, 2024
概括
呼吸样本中的挥发性有机化合物 (VOC) 在吸附管上大多稳定60天. 然而,甲醇中的VOC标准迅速降解,需要每两周新鲜的溶液进行准确的分析.
科学领域:
- 分析化学 分析化学
- 生物医学科学 生物医学科学
- 环境科学 环境科学
背景情况:
- 呼出的气息挥发性有机化合物 (VOC) 分析对于诊断至关重要.
- 吸附管收集和储存是常见的方法,但VOC的稳定性往往是未知的.
- 准确的内部标准对于VOC分析的质量控制至关重要.
研究的目的:
- 在不同温度下,在60天内存储在双吸管中的42种挥发性有机化合物的稳定性.
- 为了评估相同的42个VOCs在甲醇溶液中在-20°C下60天的稳定性.
- 为排气中的VOC样品和标准提供最佳存储实践的指导.
主要方法:
- 42个VOC的标准混合物被储存在双吸管 (Tenax® TA和Carbotrap 1TD) 中,在室温,4°C和-80°C下保存60天.
- 同样的VOC被溶解在甲醇中,并在-20°C下存储60天.
- 所有样品都使用热脱气色谱-质谱法 (TD-GC-MS) 进行了分析.
主要成果:
- 大多数挥发性有机物 (86-98%) 在60天后在吸附剂管中保持稳定,在较低的温度下稳定性更好.
- 在甲醇溶液中的VOC显示显著降解,在60天后统计下降了64%.
- 总VOC混合物和共同的内部标准在溶液中16-22天内显著降解.
结论:
- 挥发性有机物通常在吸附剂管中稳定长达60天,尤其是在低温下储存时.
- 在甲醇溶液中的VOC标准具有有限的保质期,并且需要经常准备 (至少每两周一次) 进行分析准确性.
- 样品和标准的适当存储对于可靠的呼气分析至关重要.
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