Mass Spectrometric Comparison of the Lipid Residues from Ancient Brain Remains

High resolution matrix-assisted laser desorption/ionisation Fourier transform ion-cyclotron resonance mass spectrometric (MALDI FT-ICR-MS) analyses have been carried out on lipidic extracts of preserved brain remains from 14 contexts, obtained from four archaeological sites ranging from 200 to 2,500 years old. The aim of the study was to determine whether the high molecular weight organic material reported in a similar fraction of the well-preserved York brain is a common feature of such unusually preserved brain specimens. Examination of the predominant signals in the resulting spectra in terms of signal-to-noise ratio and intensity, generated a list of peaks for comparison and interpretation. On the basis of the accurate mass measurements afforded by FT-ICR-MS, some empirical formulae were assigned. The components identified across almost all the sample extracts analysed fell into the same general class of organic molecules, that were generally functionalised with low numbers of heteroatoms (generally oxygen and nitrogen, or both). These components did not correspond to those identified in adipocere. These results pave the way for further analyses aimed at understanding the processes that take place when brain material is, unusually, preserved in the archaeological record.