Unlock Exclusive Discounts & Flash Sales! Click Here to Join the Deals on Every Wednesday!

Elemental analysis of cerebrospinal fluid (CSF) by total reflection X-ray fluorescence (TXRF) spectrometry (CAT#: STEM-ST-0203-WXH)

Introduction

CSF is a clear liquid, which is very similar to the liquid portion of blood (plasma) and contains various trace elements and other substances such as enzymes and carbohydrates. The CSF is a medium for the transportation of the chemicals to and from the brain, and also to provide buoyancy and protection for the brain.
Owing to the blood–brain barrier, the concentration of trace elements in CSF is independent of the fluctuating levels of metal ions in plasma and blood.




Principle

XRF describes the process where some high-energy radiation excites atoms by shooting out electrons from the innermost orbitals. When the atom relaxes, that is, when outer electrons fill inner shells, X-Ray fluorescence radiation is emitted.
Total-reflection X-ray fluorescence (TXRF) is a multi-element simultaneous analysis technology developed based on X-ray fluorescence (XRF). An aircooled X-ray tube generates an X-ray beam, which is reduced to a narrow energy range by a multi-layer monochromator. The fine beam impinges on a polished sample carrier at a very small angle and is totally reflected.

Applications

XRF is widely used as a fast characterization tool in many analytical labs across the world, for applications as diverse as metallurgy, forensics, polymers, electronics, archaeology, environmental analysis, geology and mining.

Procedure

1. Primary X-rays knock out an electron from one of the orbitals surrounding the nucleus within an atom of the material.
2. A hole is produced in the orbital, resulting in a high energy, unstable configuration for the atom.
3. To restore equilibrium, an electron from a higher energy, outer orbital falls into the hole. Since this is a lower energy position, the excess energy is emitted in the form of fluorescent X-rays.
The energy difference between the expelled and replacement electrons is characteristic of the element atom in which the fluorescence process is occurring – thus, the energy of the emitted fluorescent X-ray is directly linked to a specific element being analyzed.

Materials

XRF spectrometer (including X-ray source, sample chamber, analysing crystal, detector and signal processing computer)
Advertisement