Analytical Applications of AAS

AAS is a mature analytical technique. There are thousands of published methods for determining practically any element in almost any type of sample. There are books and journals devoted to analytical methods by AAS and other atomic spectrometry techniques. The bibliography provides a list of some texts on AAS. Journals such as Analytical Chemistry, Applied Spectroscopy, Journal of Analytical Atomic Spectroscopy, The Analyst, Spectroscopy Letters, and others are sources of peer-reviewed articles, but many applications articles can be found in specialized journals on environmental chemistry, food analysis, geology, and so on. The applications discussion here is necessarily limited, but the available literature is vast. 

AAS is used for the determination of all metal and metalloid elements. Nonmetals cannot be determined directly because their most sensitive resonance lines are located in the vacuum UV region of the spectrum. Neither flame nor furnace commercial atomizers can be operated in a vacuum. It is possible to determine some nonmetals indirectly by taking advantage of the insolubility of some compounds. For example, chloride ion can be precipitated as insoluble silver chloride by adding a known excess of silver ion in solution (as silver nitrate). The silver ion remaining in solution can be determined by AAS and the chloride ion concentration calculated from the change in the sUver ion concentration. Similar indirect approaches for other nonmetals or even polyatomic ions like sulfate can be devised. 

The radiation source used in AAS is an HCL or an EDL, and a different lamp is needed for each element to be determined. Because it is essentially a single-element technique, AAS 

Quantitative measurement is one of the ultimate objectives of analytical chemistry. AAS is an excellent quantitative method. It is deceptively easy to use, particularly when flame atomizers are utilized. 

Both the LOD and the sensitivity are highly dependent on the sample matrix, operating conditions, the particular instrument used, and the way in which the data are processed. 

AAS is used for the determination of all metal and metalloid elements. Nonmetals cannot be determined directly because their most sensitive resonance lines are located in the vacuum UV region of the spectrum. Neither flame nor furnace commercial atomizers can be operated in a vacuum. It is 

The radiation source used in AAS is an HCL or an EDL, and a different lamp is needed for each element to be determined (except for the new continuum source system discussed earlier). Because it is essentially a single-element technique, AAS is not well suited for qualitative analysis of unknowns. To look for more than one element requires a significant amount of sample and is a time-consuming process. For a sample of unknown composition, multielement techniques such as XRF, ICP-mass spectrometry (ICP-MS), ICP-OES, and other atomic emission techniques are much more useful and efficient. 

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