Atomic absorption spectroscope is a great way of producing
accurate results, with a rate of 0.5-5%, the result can be even better rate if
appropriate standards are used.
AAS is a sensitive method
of detection, it can measure down to parts per billion of a gram (µg dm–3 ) in
a sample. As such, it has many uses in
different areas of chemistry. For example, in medicine, it can be used
to detect trace toxin levels of atmosphere or medication. Similarly, in
pharmaceuticals, manufacturing processes, minute quantities of a catalyst used
in the process (usually a metal) are sometimes present in the final product, by
using AAS the amount of catalyst present can be determined. In industry, AAS is
used to check that the major element are present and the toxic impurities are
lower than specified.
AAS uses less argon than other methods, thus
its running costs are often lower compare to other methods.
Since the process relying upon radiation and light
absorption, it can reach previously inaccessible places. For example, miners
can now use AAS to determine if a rock contains enough elements of gold or
other precious metals to be worthwhile mining.
Lack of Versatility
Sample must be in solution or at least volatile. This
is because the substances have to be vaporised before it can be analysed.
Liquids lend themselves to this much more than solids. Besides, the technique
that allow for solid-substance testing can not be used on non-metals. This
technique has also not proved very successful for the estimation of elements
like V, Si, Mo, Ti and A1 because these elements give oxides in the flame.
Other chemicals that are found in the sample or in the
surrounding atmosphere can have an interfering and distorting effect on the
results of the study.
It is a destructive
analysis method and therefore scarce sample should be analysed by a
non-destructive method such as raman. Due to the sample preparation is time
consuming, it cannot give information as detailed as other techniques such as Nuclear
Magnetic Resonance (NMR). It is also qualitative rather than quantitative and
there are lots of compounds which are not infrared (IR) active and therefore
cannot be detected.