Atomic absorption spectroscopy has been utilized in the study of forensic sciences for many years. Using this technology, forensic scientists can perform in-depth analysis of blood samples, brain and muscle tissue, and gunshot powder residue.
Why is AAS important in forensic analysis?
Atomic Absorption Spectrometry is useful not only for the identification but also for quantitative determination of many elements present in samples. … It is found to be superior to other technique as it can be used to determine 50-60 elements from trace to large quantities. These may include metals and non-metals.
What are the applications of AAS?
- Agriculture – analyzing soil and plants for minerals necessary for growth.
- Chemical – analyzing raw chemicals as well as fine chemicals.
- Food Industry – quality assurance and testing for contamination.
- Forensic’s – substance identification.
What is AAS best suited for?
Atomic absorption spectrometry (AAS) is an easy, high-throughput, and inexpensive technology used primarily to analyze compounds in solution. As such, AAS is used in food and beverage, water, clinical, and pharmaceutical analysis.
What elements can AAS detect?
Although AAS has been known to work as a measurement technique on some semi-metals, such as boron and silicon, metals work best. A major reason for this is that the atoms in metal elements are more easily readable.
What is AAS give two examples?
The oldest and most commonly used atomizers in AAS are flames, principally the air-acetylene flame with a temperature of about 2300 °C and the nitrous oxide system (N2O)-acetylene flame with a temperature of about 2700 °C.
Is AAS qualitative or quantitative?
Atomic Absorption Spectroscopy
AAS is principally used for the trace quantitative analysis of almost seventy metals and metalloids. It is based on the absorption of UV-visible electromagnetic radiation by gaseous atoms.
What are AAS principles?
Atomic absorption spectroscopy (AAS) is based upon the principle that free atoms in the ground state can absorb light of a certain wavelength. Absorption for each element is specific, no other elements absorb this wavelength.
What is the difference between AAS and AES?
While AAS quantifies the absorption of electromagnetic radiation by well-separated neutral atoms, AES measures emission of radiation from atoms in excited states.
What is the working principle of atomic absorption spectrophotometer?
Principle of AAS
AAS quantitatively measures the concentrations of elements present in a liquid sample. It utilises the principle that elements in the gas phase absorb light at very specific wavelengths which gives the technique excellent specificity and detection limits.
Which is the correct order of AAS?
Atomic Absorption Spectrometry (AAS) Systems and Technologies. The standard AAS instrument consists of four components: the sample introduction area, the light (radiation) source, the monochromator or polychromator, and the detector (figure 1).
Why is AAS accurate?
Accuracy. AAS is a great method of producing accurate results, normally with a rate of 0.5-5%, or an even better rate if appropriate standards are used. Sensitivity. An incredibly sensitive method of detection, AAS can actually measure all the way down to parts per billion of a gram in a substance.
Which cell is used in AAS?
There are two basic atom cells (a means of converting the sample, usually a liquid, into free atoms) used in atomic absorption spectroscopy: (1) the flame and (2) the electrothermal heating of a sample cell.
Does AAS follow Beer’s law?
The concentration is calculated based on the Beer-Lambert law. … However, applying the Beer-Lambert law directly in AAS is difficult due to: variations in atomization efficiency from the sample matrix, non-uniformity of concentration and path length of analyte atoms (in graphite furnace AA).
How do you read AAS results?
If AAS (or ICP or ICP-MS) result is given in mg/l your final result will be mg/kg = ppm. If AAS (or ICP or ICP-MS) result is given in microg/l your final result will be microg/kg = ppb.
Which is the most widely used flame in AAS?
1.1 Flame atomic absorption spectrometry. Chromium is typically determined by flame AAS using an air-acetylene flame or a nitrous oxide-acetylene flame. Although chromium has a large number of resonance lines of similar sensitivity, the 357.9 nm line is most commonly used.