Topographic and quantitative microanalysis of human central nervous system tissue using synchrotron radiation

Synchrotron microbeam X-ray fluorescence (μ-SXRF) was applied for topographic and quantitative analysis of selected elements in human brain and spinal cord. The main goal of the study is a better understanding of the role of elements, mainly metals, in processes leading to degeneration and atrophy of nerve cells in cases of two neurodegenerative disorders, i.e. Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS). The samples were taken during the autopsy from patients deceased with PD, ALS, and from a patient who died due to non-neurological conditions. In measurements, a 5 x 2 μm 2 X-ray beam was applied for scanning the thin tissue slices. Two-dimensional maps of elemental distribution were compared with histopathological sections. The results obtained showed that the spatial distribution of selected elements precisely corresponds to the microscopic views of scanned area of tissue. Moreover, differences in accumulation of selected elements in nerve cell bodies and areas representing white matter between patients affected by PD, ALS and the control case were noticed. The present investigation showed that the μ-SXRF technique is suitable for elemental analysis at the single cell level in applications in neurological research.