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Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis of cellular glycerophospholipids enabled by multiplexed solvent dependent analyte-matrix interactions.

ABSTRACT: A matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) based approach was developed for the rapid analyses of cellular glycerophospholipids. Through multiplexed solvent-enabled optimization of analyte-matrix interactions during the crystallization process, over a 30-fold increase in S/N was achieved using 9-aminoacridine as the matrix. The linearity of response (r(2) = 0.99) and dynamic range of this method (over 2 orders of magnitude) were excellent. Moreover, through multiplexing ionization conditions by generating suites of different analyte-matrix interactions in the absence or presence of different alkali metal cations in the matrix, discrete lipid classes were highly and selectively ionized under different conditions resulting in the de facto resolution of lipid classes without chromatography. The resultant decreases in spectral complexity facilitated tandem mass spectrometric analysis through high energy fragmentation of lithiated molecular ions that typically resulted in informative fragment ions. Anionic phospholipids were also detected as singly negatively charged species that could be fragmented using MALDI tandem mass spectrometry leading to structural assignments. Collectively, these results identify a rapid, sensitive, and highly informative MALDI-TOF MS approach for analysis of cellular glycerophospholipids directly from extracts of mammalian tissues without the need for prior chromatographic separation.

SUBMITTER: Sun G

PROVIDER: S-EPMC2963173 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis of cellular glycerophospholipids enabled by multiplexed solvent dependent analyte-matrix interactions.

Sun Gang G Yang Kui K Zhao Zhongdan Z Guan Shaoping S Han Xianlin X Gross Richard W RW

Analytical chemistry 20080904 19

A matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) based approach was developed for the rapid analyses of cellular glycerophospholipids. Through multiplexed solvent-enabled optimization of analyte-matrix interactions during the crystallization process, over a 30-fold increase in S/N was achieved using 9-aminoacridine as the matrix. The linearity of response (r(2) = 0.99) and dynamic range of this method (over 2 orders of magnitude) were excellent. Moreo ...[more]

PMID: 18767869

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Dataset Information

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis of cellular glycerophospholipids enabled by multiplexed solvent dependent analyte-matrix interactions.

Publications

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis of cellular glycerophospholipids enabled by multiplexed solvent dependent analyte-matrix interactions.

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