Pinpointing Double Bonds in Lipids by Paternò‐Büchi Reactions and Mass Spectrometry

Abstract

The positions of double bonds in lipids play critical roles in their biochemical and biophysical properties. In this study, by coupling Paternò-Büchi (P-B) reaction with tandem mass spectrometry, we developed a novel method that can achieve confident, fast, and sensitive determination of double bond locations within various types of lipids. The P-B reaction is facilitated by UV irradiation of a nanoelectrospray plume entraining lipids and acetone. Tandem mass spectrometry of the on-line reaction products via collision activation leads to the rupture of oxetane rings and the formation of diagnostic ions specific to the double bond location.

Lipid Desaturation Is a Metabolic Marker and Therapeutic Target of Ovarian Cancer Stem Cells

“…To test the hypothesis, we performed whole lipid analysis by mass spectrometry. First, we extracted free fatty acids from cells grown as monolayers or spheres (Ma and Xia, 2014) and analyzed by Electrospray Ionization Mass Spectrometry (ESI-MS). As shown in the mass spectra (Fig.…”

“…Free fatty acid extraction was performed following previous protocol (Ma and Xia, 2014). Cell pellets were resuspended in 300 μL PBS, mixed with 1 ml methanol and acidified with HCl to 25 mM final concentration.…”

Photochemical Tagging for Quantitation of Unsaturated Fatty Acids by Mass Spectrometry

“…tagged FA 17:1 ( m/z 325), led to dominant tag loss (−58 Da) and a pair of C=C diagnostic ions with a signature 26 Da mass separation (Figure 1c). 11 This set of experiments demonstrates that the processes of acetone tagging in solution and acetone de-tagging in gas phase are efficient.…”

Pinpointing Double Bond and sn-Positions in Glycerophospholipids via Hybrid 193 nm Ultraviolet Photodissociation (UVPD) Mass Spectrometry

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