On the isobaric space of 25‐hydroxyvitamin D in human serum: potential for interferences in liquid chromatography/tandem mass spectrometry, systematic errors and accuracy issues

作者：Yulin Qi, Timon Geib, Pascal Schorr, Florian Meier, Dietrich A. Volmer · 发表于：Rapid Communications in Mass Spectrometry · 年份：2014 · DOI：10.1002/rcm.7075 · 被引用次数：60 · 研究领域：Vitamin D Research Studies、Metabolomics and Mass Spectrometry Studies、Biotin and Related Studies

RATIONALE: Isobaric interferences in human serum can potentially influence the measured concentration levels of 25-hydroxyvitamin D [25(OH)D], when low resolving power liquid chromatography/tandem mass spectrometry (LC/MS/MS) instruments and non-specific MS/MS product ions are employed for analysis. In this study, we provide a detailed characterization of these interferences and a technical solution to reduce the associated systematic errors. METHODS: Detailed electrospray ionization Fourier transform ion cyclotron resonance (FTICR) high-resolution mass spectrometry (HRMS) experiments were used to characterize co-extracted isobaric components of 25(OH)D from human serum. Differential ion mobility spectrometry (DMS), as a gas-phase ion filter, was implemented on a triple quadrupole mass spectrometer for separation of the isobars. RESULTS: HRMS revealed the presence of multiple isobaric compounds in extracts of human serum for different sample preparation methods. Several of these isobars had the potential to increase the peak areas measured for 25(OH)D on low-resolution MS instruments. A major isobaric component was identified as pentaerythritol oleate, a technical lubricant, which was probably an artifact from the analytical instrumentation. DMS was able to remove several of these isobars prior to MS/MS, when implemented on the low-resolution triple quadrupole mass spectrometer. CONCLUSIONS: It was shown in this proof-of-concept study that DMS-MS has the potential to signific...