Hefei National Laboratory for Physical Sciences at the Microscale, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, China.
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, China.
Rapid Commun Mass Spectrom. 2020 May 30;34(10):e8759. doi: 10.1002/rcm.8759.
Accurate measurement of trace compounds in blood samples is important in clinical diagnosis and life science. Ambient ionization mass spectrometry, however, suffers from the matrix effect when dealing with complex samples such as blood. Therefore, it is important to reduce the matrix effects in blood samples.
A low-cost and disposable Teflon tube was used as a platform to precipitate the protein in blood. The analytes are extracted into organic solvent, and the precipitated protein can be adsorbed by the chromatography paper inserted. Therefore, the Teflon tube after precipitation can be directly subjected to paper spray ionization mass spectrometry, achieving one-step analysis of blood.
High sensitivity and satisfactory stability were achieved for pharmaceuticals, acids, and endogenic metabolites in blood. The absolute signal intensities of characteristic product ions of the tested analytes were 8-20 times higher after protein precipitation than those obtained using paper spray. Detection limits and quantitative performance were evaluated for three drugs: carbamazepine, metformin, and tioconazole. In addition, the limits of detection and quantitation were improved 9-14- and 8-12-fold, respectively.
Protein precipitation coupled to paper spray with a tube and then to mass spectrometry was successfully achieved and applied in the one-step analysis of trace compounds in blood samples. The experimental results showed that this method was sensitive, stable, convenient, and economic for the direct analysis of blood.
准确测量血液样本中的痕量化合物对于临床诊断和生命科学非常重要。然而，环境电离质谱在处理复杂样品（如血液）时会受到基质效应的影响。因此，减少血液样品中的基质效应非常重要。
使用低成本且一次性的聚四氟乙烯管作为平台沉淀血液中的蛋白质。分析物被提取到有机溶剂中，沉淀的蛋白质可以被插入的滤纸吸附。因此，沉淀后的聚四氟乙烯管可以直接进行纸喷雾电离质谱分析，实现血液的一步分析。
在血液中的药物、酸和内源性代谢物方面实现了高灵敏度和令人满意的稳定性。与纸喷雾相比，经过蛋白质沉淀后，测试分析物的特征产物离子的绝对信号强度提高了 8-20 倍。对三种药物（卡马西平、二甲双胍和噻康唑）进行了检测限和定量性能评估。此外，检测限和定量限分别提高了 9-14 倍和 8-12 倍。
成功实现了管内沉淀与纸喷雾相结合，然后与质谱联用，用于血液中痕量化合物的一步分析。实验结果表明，该方法对于血液的直接分析具有灵敏、稳定、方便和经济的特点。
