Detection of oxidative species for 4-phenoxyphenol derivatives during the electrospray ionization process.
Analyses by flow injection as well as liquid chromatography/mass spectrometry (LC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) were performed with four 4-phenoxyphenol derivatives. When ambient temperature nitrogen gas was used to facilitate solvent evaporation, [M + H]+, [M + NH4]+, and [2M + NH4]+ ions were observed as the major ions. As the nitrogen gas temperature increased from ambient to 250 and 450 degrees C, [M]+*, [M - 1]+ and [M + 15]+ ions were the predominant ions. Heat-induced oxidation was found to be the primary source for the formation of oxidative species. Aqueous solvents were found to be essential for the formation of the [M + 15]+ ions. The [M]+* and [M + 15]+ ions were further characterized by tandem mass spectrometry. Based on the MS/MS data, it was proposed that the [M + 15]+ ions were the in-source generated 1,2-quinone ions.
Wu
Y
Y
Department of Pharmaceutical Research and Development, Merck Research Laboratories, West Point, PA 19486, USA. yunhui_wu@merck.com
Wang
H
H
D013058:Mass Spectrometry; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry*; D011809:Quinones / Q000737:chemistry; D013696:Temperature
D010636:Phenols; D011809:Quinones