Quantification of Pentafluorobenzyl Oxime Derivatives of Long Chain Aldehydes by GC–MS Analysis

Abstract

Negative ion mass spectrometric techniques for compounds having good ionization properties, such as pentafluorobenzyl derivatives, are believed to be more sensitive than positive ion methods. In this study we develop a technique of quantification of long-chain aldehydes by analysis of their pentafluorobenzyl oxime derivatives utilizing gas chromatography-mass spectrometry in the negative ion chemical ionization mode. We establish that separation of plasmalogens prior to pentafluorobenzyl derivatization is essential and achieve this separation over a silica column. We further demonstrate the sensitivity of this method and utilize this technique to identify increases in hexadecanal and octadecanal in 3-aminotriazole treated human neutrophils.

Oxidation of Plasmalogen, Low‐Density Lipoprotein and RAW 264.7 Cells by Photoactivatable Atomic Oxygen Precursors

“…Extraction was conducted three times per sample. After lipid extraction, samples underwent silica extraction on LC‐Si (Supelco) columns using chloroform solvent to separate plasmalogens from free fatty aldehydes . The samples were then prepared for GC‐MS analysis by derivatization with pentafluorobenzyl (PFB) hydroxylamine.…”

In vitrooxidations of low-density lipoprotein and RAW 264.7 cells with lipophilic O(3P)-precursors

“…Aer lipid extraction, samples underwent silica extraction on LC-Si (Supelco) columns using chloroform to separate plasmalogens from free fatty aldehydes. 55 The samples were then prepared for GC-MS analysis by derivatization with penta-uorobenzyl (PFB) hydroxylamine. Derivatization with PFB hydroxylamine was performed by resuspending the reaction products in 300 mL of ethanol and 300 mL of PFB hydroxylamine (6 mg mL À1 ) in water.…”

Comparison of Low‐Density Lipoprotein Oxidation by Hydrophilic O(3P)‐Precursors and Lipid‐O(3P)‐Precursor Conjugates

“…The samples were extracted twice using the Bligh–Dyer lipid extraction technique, in the presence of 10 pmol 2‐[ d5 ]‐hexadecenal (2‐[ d5 ]‐HDEA) (16). Post lipid extraction, samples were purified using silica extraction on LC‐Si (Supelco) columns that separate free fatty aldehydes from plasmalogens (17). Samples were dried using an N‐Evap system then derivatized with PFB.…”