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
- (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.
- D. Harvey, “Modern Analytical Chemistry”, McGraw-Hill Companies Inc., 2000
- D.A. Skoog, F.J. Holler, T.A. Nieman, “Principles of Instrumental Analysis”. Saunders College Publishing: Philadelphia, 1998.
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