Atomic emission and Atomic Absorption Spectroscopy Applications and differences- By Gomal Amin

Atomic absorption spectroscopy Applications

·         Atomic absorption is widely used for the analysis of trace metals in a variety of sample matrices.

·         It is used to determine the metal concentration in water and wastewater, air, blood, urine, muscle tissue, hair, milk, breakfast cereals, shampoos, alloys, industrial plating baths, gasoline, oil, sediments, and rocks.

·         Water analysis of different metals e.g. Ca, Mg, Fe, Si, Al, Ba content is done by AAS.

·         Food analysis and analysis of animal feedstuffs (Mn, Fe, Cu, Cr, Se, Zn)

·         Analysis of additives in lubricating oils and greases (Ba, Ca, Na, Li, Zn, Mg)

·         Analysis of soils can be done by using AAS.

·         Clinical analysis (blood samples: whole blood, plasma, serum ( Ca, Mg, Li, Na, K, Fe)

·         Apart from above it can be used in Forensics, Manufacturing, Petrochemical, Drug discovery and design, Metallurgy, and Mining.

Atomic Emission Spectroscopy Applications

·         The principal application of atomic emission spectroscopy is to determine the quantity of a particular element in a given sample or to do Quantitative analysis of sample.

·         The various methods of atomic emission spectroscopy are utilized to examine different substances such as foods and drinks, motor oil and soil samples.

·       Atomic Emission Spectroscopy is predominantly utilized in space research labs by NASA and ESA.

·         It is also used for assisting in various military operations.

·    This emission spectrum can be used as a unique characteristic for qualitative identification of the element.

·         Atomic emission using electrical arcs has been widely used in qualitative analysis.

·         Used in Determination of metals in industrial wastewaters.

·         Used in exploration, mining and processing of metal (ore).

·         Pharmaceutical companies and labs use AES for identification and characterization of biological and chemical samples. 

Differentiate between AAS and AES

The difference between the both spectroscopy techniques depends upon its instrumentation and the main working principal. Following are some points differentiating the AES and AAS.

AAS:  If light of just the right wavelength impinges on a free, ground state atom, the atom may absorb the light as it enters an excited state in a process known as atomic absorption. The energy is absorbed in the excitation process. In AAS, when monochromatic light is bombarded through the sample the atoms absorb energy, and the extent of absorption is recorded. In AAS, a monochromatic light source is used to provide energy for the excitation of electrons. In AAS, there is a separate chamber for atomization of the sample.

AES: Emission spectroscopy is a spectroscopic technique which examines the wavelengths of photons emitted by atoms or molecules during their transition from an excited state to a lower energy state. Each element emits a characteristic set of discrete wavelengths according to its electronic structure, by observing these wavelengths the elemental composition of the sample can be determined. Flame is used as light source in AES. In AES, atomization takes place step by step upon the introduction of the sample to the flame.