Understanding isotopes, isomers, and isobars in mass spectrometry
Katharina Habler, Arber Rexhaj, Manuela Adling-Ehrhardt, Michael Vogeser
Abstract
Mass spectrometry (MS) is a versatile analytical tool used in various fields such as biochemistry, pharmacology, omics, and clinical analysis for determining and quantifying compounds based on their molecular mass and structure through the mass-to-charge ratio. While MS offers high specificity and selectivity, it encounters challenges including matrix effects, in-source fragmentation, and other interferences caused by natural isotopic abundance, as well as isomeric and isobaric compounds. These challenges can impede accurate qualitative and quantitative analysis. Visual aids such as graphical illustrations can help elucidate the chemical differences and similarities among isotopes, isomers, and isobaric compounds.