AAS: Figures of Merit

1
AAS Figures of Merit

• Detection limits Generally lower LOD for very
  volatile elements
• Higher LOD for carbide-forming elements
  (e.g. Ba, B, Ca, Mo, W, V, Zr)
• Concentration in GF up to 1000 times higher
  than in flame much lower LOD for GF.
• Lower LOD for GF-AAS than ICP-AES unless
• atomization requires high temperature
• Generally similar LOD for flame-AAS and
  ICP-AES
• Improve LOD by adding ethanol or methanol
  to decrease droplet surface tension during
  nebulization
• Chemical HCl often avoided as acid in GF-AAS
  because
• interferences metal chlorides are more
  volatile than sulfates or
• phosphates.
• Addition of Cs salt to sample suppresses
  ionization.
• La precipitates phosphate, facilitating Ca
  analysis.
• Proteins may clog burners and are
  precipitated with
• trichloroacetic acid.