Total iron determination by atomic absorption spectroscopy

Total iron determination by atomic absorption spectroscopy 

Total iron levels (free -I- bound) in a range of biological systems such as urine, plasma, membranes, solution etc. can be determined applying atomic absorption spectroscopy. 

Concentrated nitric acid - 70% spectrosil (BDH special for atomic absorption spectroscopy - iron level 0.2 ppm). 

The samples are heated in a dry block at 170°C until the sample is completely dry. A 2 ml aliquot of fuming nitric acid is carefully added using a glass calibrated pipette, the tubes covered with a large glass marble to prevent evaporation and the sample is heated at 170°C to digest the sample. After 20 min the marble is removed, and the heating continued until the nitric acid has completely evaporated. 

The digested material is resuspended in a further 2 ml aliquot of 70% nitric acid and utilized for atomic absorption spectroscopy. Blanks containing the same volume of the appropriate buffer are similarly taken through the entire process. 

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