Benton Christopher M, Lim Chang Kee, Moniz Caje, Jones Donald J L
Clinical Biochemistry, King's College Hospital, Denmark Hill, London, SE5 9RS, UK; Cancer Studies and Molecular Medicine, RKCSB, University of Leicester, Leicester, LE2 7LX, UK.
Biomed Chromatogr. 2013 Dec;27(12):1782-7. doi: 10.1002/bmc.2994. Epub 2013 Jul 29.
Biological and clinical samples for porphyrin and porphyrinogen analyses by liquid chromatography-tandem mass spectrometry (LC-MS/MS) are often contaminated with poly(ethylene)glycol (PEG), which complicates the interpretation of mass spectra and characterisation of new porphyrin metabolites. Two contaminating PEG molecules (m/z 833 and m/z 835) were completely separated from uroporphyrin I (m/z 831) by travelling wave ion mobility spectrometry and characterised by tandem mass spectrometry. One of the PEG species (m/z 835) also co-eluted with uroporphyrinogen I (m/z 837) and was unresolvable by travelling wave ion mobility spectrometry/MS, therefore contaminating the MS/MS mass spectra owing to isotope distribution. These PEG species, with the M + H ions at m/z at 833 and/or m/z 835, co-eluted with uroporphyrin I and uroporphyrinogen I by LC-MS/MS and could be wrongly identified as uroporphomethenes.
用于通过液相色谱 - 串联质谱法（LC-MS/MS）分析卟啉和卟啉原的生物和临床样本常常被聚乙二醇（PEG）污染，这使得质谱的解释以及新的卟啉代谢物的表征变得复杂。通过行波离子淌度质谱法，两种污染性PEG分子（m/z 833和m/z 835）与尿卟啉I（m/z 831）完全分离，并通过串联质谱法进行了表征。其中一种PEG物质（m/z 835）还与尿卟啉原I（m/z 837）共洗脱，并且通过行波离子淌度质谱法/质谱无法分辨，因此由于同位素分布而污染了MS/MS质谱。这些在m/z为833和/或m/z 835处带有M + H离子的PEG物质，通过LC-MS/MS与尿卟啉I和尿卟啉原I共洗脱，并且可能被错误地鉴定为尿卟啉甲川。
