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Phosphonium labeling for increasing metabolomic coverage of neutral lipids using electrospray ionization mass spectrometry.

ABSTRACT: Mass spectrometry has become an indispensable tool for the global study of metabolites (metabolomics), primarily using electrospray ionization mass spectrometry (ESI-MS). However, many important classes of molecules such as neutral lipids do not ionize well by ESI and go undetected. Chemical derivatization of metabolites can enhance ionization for increased sensitivity and metabolomic coverage. Here we describe the use of tris(2,4,6,-trimethoxyphenyl)phosphonium acetic acid (TMPP-AA) to improve liquid chromatography (LC)/ESI-MS detection of hydroxylated metabolites (i.e. lipids) from serum extracts. Cholesterol which is not normally detected from serum using ESI is observed with attomole sensitivity. This approach was applied to identify four endogenous lipids (hexadecanoyl-sn-glycerol, dihydrotachysterol, octadecanol, and alpha-tocopherol) from human serum. Overall, this approach extends the types of metabolites which can be detected using standard ESI-MS instrumentation and demonstrates the potential for targeted metabolomics analysis.

SUBMITTER: Woo HK

PROVIDER: S-EPMC3052201 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Phosphonium labeling for increasing metabolomic coverage of neutral lipids using electrospray ionization mass spectrometry.

Woo Hin-Koon HK Go Eden P EP Hoang Linh L Trauger Sunia A SA Bowen Benjamin B Siuzdak Gary G Northen Trent R TR

Rapid communications in mass spectrometry : RCM 20090601 12

Mass spectrometry has become an indispensable tool for the global study of metabolites (metabolomics), primarily using electrospray ionization mass spectrometry (ESI-MS). However, many important classes of molecules such as neutral lipids do not ionize well by ESI and go undetected. Chemical derivatization of metabolites can enhance ionization for increased sensitivity and metabolomic coverage. Here we describe the use of tris(2,4,6,-trimethoxyphenyl)phosphonium acetic acid (TMPP-AA) to improve ...[more]

PMID: 19449318

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Dataset Information

Phosphonium labeling for increasing metabolomic coverage of neutral lipids using electrospray ionization mass spectrometry.

Publications

Phosphonium labeling for increasing metabolomic coverage of neutral lipids using electrospray ionization mass spectrometry.

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