Kendrick Analysis and Complex Isotopic Patterns: A Case Study of the Compositional Analysis of Pristine and Heated Polybrominated Flame Retardants by High-Resolution MALDI Mass Spectrometry

High-Resolution Mass Spectrometry and Nontraditional Mass Defect Analysis of Brominated Historical Pigments

“…To simplify the identification of the native conformation of the geranium lake, we selected the mass of the most abundant isotope of a single tetra-brominated eosin molecule, ([C 20 H 9 O 5 79 Br 2 81 Br 2 ] + , abbreviated as EoBr 4 ), as a base unit ( R = 648.7132). The advantages of choosing the most abundant isotope, over the monoisotopic mass, for mass rescaling and the nature of its impact on point alignments in Kendrick analysis have been already discussed to track brominated flame retardants …”

“…The presence of a heteroatom such as Br, present not only in the lake, but also in the side products, produced a rich and specific isotopic pattern that makes the evaluation of the mass spectrum more complicated ( monoisotopic mass, for mass rescaling and the nature of its impact on point alignments in Kendrick analysis have been already discussed to track brominated flame retardants. 24 A pattern of brominated species can be visually recognized in the nontraditional Kendrick plot or rescaled KMD plot of the aluminum-and lead-based lakes (Figure 1). These plots show a horizontal alignment of brominated species differing along the m/z axis by the repeating unit (in this case a tetrabrominated eosin, EoBr 4 ).…”