Atomic adsorption spectroscopy (AAS) is used to measure the concentration of metallic elements in different materials. As an analytical technique, it uses electromagnetic wavelengths, coming from a light source. Distinct elements will absorb these wavelengths differently, giving a picture of what concentrations of a specific element there is in the material being tested.
Using AAS, you can measure for a specific element in a material, based on the amount of light absorbed at a defined wavelength, which corresponds to the known characteristics of the element under test.
AAS provides a high degree of accuracy, with results normally produced in a range of 0.5-5% accuracy. It is a highly sensitive test method and, depending on the material under test, can measure parts per billion of a gram.
This high sensitivity makes it ideal for medical and pharmaceutical applications where it can be used to detect trace toxins. It can also be used in industrial applications such as mining, where it is often used to test rocks for suitability for mining.
AAS can be used to determine concentrations of over 65 elements using a relatively simple process, requiring minimal training to conduct sample analysis. It also allows for a high sample throughput while being inexpensive compared to other analytical techniques. This combination of benefits make the technique attractive from a commercial perspective.
Atomic absorption spectroscopy has different laboratory and testing applications in industrial, clinical and research settings, as a crucial component in various processes including quality control, toxicology and environmental testing.
As a method, AAS can analyse the content of certain metals in various materials. For example:
AAS can be used to determine metallic elements in environmental, pharmaceutical, chemical, petrochemical and food and beverage applications. Depending on the application, technicians can use flame (FAAS), graphite furnace (GFAAS) or hydride generation AA (HGAAS).
FAAS, which is the original and most common type of AAS, uses flame to atomise samples in the instrument. In applications, measuring testing for one element in a material in substantial concentrations, FAAS is an effective analytical technique. When sample size is limited or the analyte is present in low concentrations, GFAAS or GHAAS techniques are more suitable. SciMed supplies a range of flame, graphite furnace and hydride generation AAS instruments, view the full range of AAS instrumentation here.
SciMed also supplies Analytik Jena’s unique Continuum-Source High Resolution ContrAA system for high-resolution multi-element analysis. The instrument design allows it to use a single light source for all elements, allowing it to analyse multiple elements simultaneously. This results in a higher sample throughput than can be achieved using a standard line source AAS instrument. To find out more, visit https://www.scimed.co.uk/product/contraa-series-high-resolution-continuum-source-aas/
Sample preparation is as simple as weighing a fixed amount of the sample and diluting it into a solution before loading into the AAS instrument, which will then vapourise the sample before atomising it. There are two ways to atomise the sample:
Once atomised, an electromagnetic beam is passed through the sample, which will absorb some of this radiation. This absorbance will be measured by the machine and results displayed on the screen, which can then be used to determine concentrations using the Beer-Lambert law; A = εcl.
One of the most important aspects of AAS experiments is using reliable standards to create a calibration curve, which will help determine the concentration of the element under test by comparing to results for known concentrations. To help with this, SciMed supplies certified standards for a variety of analytical techniques, including AAS.
To view SciMed’s range of atomic adsorption spectroscopy instrumentation, visit https://www.scimed.co.uk/product-category/atomic-absorption-spectroscopy-aas/.
Alternatively, to speak to one of SciMed’s team about how you can use AAS, by clicking the button below.