Comparison between ammonium formate and ammonium fluoride in the analysis of stratum corneum lipids by reversed phase chromatography coupled with high resolution mass spectrometry

Effects of ammonium formate on the separation and detection of ceramides

Using a gradient elution with ammonium formate as mobile phase modifier at the 5 mM concentration, the formation of the stable anionic adduct [M + HCOO]⁻ was promoted, while the production of the deprotonated molecular ion [M − H]⁻ was less favored. In some cases, the prominent peak due to the formate adduct may interfere with the chromatographic identification of the species of interest. In fact, when operating an extracted-ion chromatogram (EIC) of the m/z 680.6198, corresponding to the…