J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23, Prague 8, Czech Republic.
Mass Spectrom Rev. 2011 Mar-Apr;30(2):236-67. doi: 10.1002/mas.20303. Epub 2010 Jul 20.
The development of selected ion flow tube mass spectrometry, SIFT-MS, is described from its inception as the modified very large SIFT instruments used to demonstrate the feasibility of SIFT-MS as an analytical technique, towards the smaller but bulky transportable instruments and finally to the current smallest Profile 3 instruments that have been located in various places, including hospitals and schools to obtain on-line breath analyses. The essential physics and engineering principles are discussed, which must be appreciated to design and construct a SIFT-MS instrument. The versatility and sensitivity of the Profile 3 instrument is illustrated by typical mass spectra obtained using the three precursor ions H(3)O(+), NO(+) and O(2)(+)·, and the need to account for differential ionic diffusion and mass discrimination in the analytical algorithms is emphasized to obtain accurate trace gas analyses. The performance of the Profile 3 instrument is illustrated by the results of several pilot studies, including (i) on-line real time quantification of several breath metabolites for cohorts of healthy adults and children, which have provided representative concentration/population distributions, and the comparative analyses of breath exhaled via the mouth and nose that identify systemic and orally-generated compounds, (ii) the enhancement of breath metabolites by drug ingestion, (iii) the identification of HCN as a marker of Pseudomonas colonization of the airways and (iv) emission of volatile compounds from urine, especially ketone bodies, and from skin. Some very recent developments are discussed, including the quantification of carbon dioxide in breath and the combination of SIFT-MS with GC and ATD, and their significance. Finally, prospects for future SIFT-MS developments are alluded to.
本文描述了选定离子流管质谱（SIFT-MS）的发展历程，从最初作为大型 SIFT 仪器的改进版本，用于展示 SIFT-MS 作为分析技术的可行性，到后来更小但体积更大的可运输仪器，最后到当前最小的 Profile 3 仪器，这些仪器已经被安置在各种地方，包括医院和学校，以进行在线呼吸分析。本文讨论了设计和构建 SIFT-MS 仪器所需的基本物理和工程原理。通过使用三种前体离子 H(3)O(+)、NO(+)和 O(2)(+)·获得的典型质谱图，说明了 Profile 3 仪器的多功能性和灵敏度，并且强调了需要在分析算法中考虑差分离子扩散和质量歧视，以获得准确的痕量气体分析。通过几个试点研究的结果说明了 Profile 3 仪器的性能，包括：（i）在线实时定量分析健康成年人和儿童的几种呼吸代谢物，这提供了代表性的浓度/人群分布，以及通过口腔和鼻腔呼气的比较分析，识别了系统性和口腔生成的化合物；（ii）药物摄入对呼吸代谢物的增强作用；（iii）鉴定 HCN 作为气道假单胞菌定植的标志物；（iv）尿液，特别是酮体，以及皮肤排放挥发性化合物。还讨论了一些最新的发展，包括呼吸中二氧化碳的定量和 SIFT-MS 与 GC 和 ATD 的结合及其意义。最后，提到了未来 SIFT-MS 发展的前景。
