Advantages and Disadvantages of Atomic Absorption Spectrometry and Graphite Furnace

Advantages and Disadvantages of Atomic Absorption Spectrometry and Graphite Furnace

 

Advantages and Disadvantages of Atomic Absorption Spectrometry and Graphite Furnace

Atomic Absorption Spectrometry (AAS) is an analytical technique that measures the concentration of an element by measuring the amount of light (intensity of light) that is absorbed - at a characteristic wavelength - when it passes through a cloud of atoms of this element.

As the number of atoms in the light path increases, the amount of light absorbed increases in a predictable way.

The main advantages of AAS  are given below:

  • High sample throughput
  • Easy to use
  • High precision
  • Inexpensive technique

The main disadvantages of AAS  are as follows:

  • only solutions can be analyzed
  • less sensitivity compared to graphite furnace
  • relatively large sample quantities are required (1-3 ml)
  • problems with refractory elements

 

Graphite furnace is by far the most advanced and widely used high sensitivity sampling technique for atomic absorption .

The main advantages of graphite furnace (GFAAS) over AAS can be summarized as follows:

  • Slurries and solid samples can be analyzed in addition to samples in solution
  • It shows greater sensitivity than AAS
  • Smaller quantities of sample are required (normally 5-60 μL)
  • The atomization process is more efficient comparing to AAS

The main disadvantages of  graphite furnace are given :

  • It is an expensive technique
  • Low sample throughput
  • It requires experienced operators.

 


Relevant Posts

Atomic Absorption Spectrometry (AAS)

Sampling Techniques for Atomic Absorption Spectrometry

 


References

  1. (a) A. Walsh, Anal. Chem., 63, 933A–941A, 1991 (b) S.R. Koirtyohann, Anal. Chem., 63, 1024A–1031A, 1991 (c) W. Slavin, Anal. Chem., 63, 1033A–1038A, 1991.
  2. D. Harvey,  “Modern Analytical Chemistry”, McGraw-Hill Companies Inc., 2000
  3. D.A. Skoog, F.J.  Holler, T.A.  Nieman,  “Principles of Instrumental Analysis”. Saunders College Publishing: Philadelphia, 1998.

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