Determination of selenium in rat brain by synchrotron radiation X-ray fluorescence

Selenium, an ubiquitous essential trace-element is known to be particularly difficult to measure especially in brain. First, it is a non metal, next, at very low concentration (below ppm). at last, the brain matter very rich in lipids. make the digestion specially uneasy. Using synchrotron radiation induced X-ray fluorescence analysis (SXRF), selenium in rat brain was measured equal to C-Se = 124 +/- 5.4 ppb with a MDL (minimum detection limit) of 20 ppb. The obtained values should be used as a first step to study human brain on extremely small and specific locations. With the development of aging pathologies (such as Alzheimers or Parkinson's disease...), it matters to get informations about selenium known as an anti-aging element. The obtained values from rat, near of man's. may also highlight it as a potential animal model system for studying selenium in human brain.