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Title: Formation of iron complexs from trifluoroacetic acid based liquid chromatography mobile phases as interference ions in liquid chromatography/electrospray ionization mass spectrometric analysis

Abstract

Two unexpected singly charged ions at m/z 1103 and 944 have been observed in mass spectra obtained from electrospray ionization-mass spectrometric analysis of liquid chromatography effluents with mobile phases containing trifluoroacetic acid. Accurate mass measurement and tandem mass spectrometry studies revealed that these two ions are not due to any contamination from solvents and chemicals used for mobile and stationary phases or from the laboratory atmospheric environment. Instead these ions are clusters of trifluoroacetic acid formed in association with acetonitrile, water and iron from the stainless steel union used to connect the column with the electrospray tip and to apply high voltage; the molecular formulae are Fe+((OH)(H2O)2)9(CF3COOH)5 and Fe+((OH)(H2O)2)6 (CF3COOH)5.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1015517
Report Number(s):
PNNL-SA-68066
Journal ID: ISSN 0951-4198; RCMSEF; 24698; 400412000; TRN: US201111%%637
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Rapid Communications in Mass Spectrometry, 25(10):1452-1456; Journal Volume: 25; Journal Issue: 10
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ACETONITRILE; CHROMATOGRAPHY; CONTAMINATION; IONIZATION; IRON; MASS SPECTRA; MASS SPECTROSCOPY; SOLVENTS; STAINLESS STEELS; WATER; Electrospray; System; Contaminants; Cell; Environmental Molecular Sciences Laboratory

Citation Formats

Shukla, Anil K., Zhang, Rui, Orton, Daniel J., Zhao, Rui, Clauss, Therese RW, Moore, Ronald J., and Smith, Richard D. Formation of iron complexs from trifluoroacetic acid based liquid chromatography mobile phases as interference ions in liquid chromatography/electrospray ionization mass spectrometric analysis. United States: N. p., 2011. Web. doi:10.1002/rcm.5017.
Shukla, Anil K., Zhang, Rui, Orton, Daniel J., Zhao, Rui, Clauss, Therese RW, Moore, Ronald J., & Smith, Richard D. Formation of iron complexs from trifluoroacetic acid based liquid chromatography mobile phases as interference ions in liquid chromatography/electrospray ionization mass spectrometric analysis. United States. doi:10.1002/rcm.5017.
Shukla, Anil K., Zhang, Rui, Orton, Daniel J., Zhao, Rui, Clauss, Therese RW, Moore, Ronald J., and Smith, Richard D. Mon . "Formation of iron complexs from trifluoroacetic acid based liquid chromatography mobile phases as interference ions in liquid chromatography/electrospray ionization mass spectrometric analysis". United States. doi:10.1002/rcm.5017.
@article{osti_1015517,
title = {Formation of iron complexs from trifluoroacetic acid based liquid chromatography mobile phases as interference ions in liquid chromatography/electrospray ionization mass spectrometric analysis},
author = {Shukla, Anil K. and Zhang, Rui and Orton, Daniel J. and Zhao, Rui and Clauss, Therese RW and Moore, Ronald J. and Smith, Richard D.},
abstractNote = {Two unexpected singly charged ions at m/z 1103 and 944 have been observed in mass spectra obtained from electrospray ionization-mass spectrometric analysis of liquid chromatography effluents with mobile phases containing trifluoroacetic acid. Accurate mass measurement and tandem mass spectrometry studies revealed that these two ions are not due to any contamination from solvents and chemicals used for mobile and stationary phases or from the laboratory atmospheric environment. Instead these ions are clusters of trifluoroacetic acid formed in association with acetonitrile, water and iron from the stainless steel union used to connect the column with the electrospray tip and to apply high voltage; the molecular formulae are Fe+((OH)(H2O)2)9(CF3COOH)5 and Fe+((OH)(H2O)2)6 (CF3COOH)5.},
doi = {10.1002/rcm.5017},
journal = {Rapid Communications in Mass Spectrometry, 25(10):1452-1456},
number = 10,
volume = 25,
place = {United States},
year = {Mon May 30 00:00:00 EDT 2011},
month = {Mon May 30 00:00:00 EDT 2011}
}
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