Atomic Absorption Spectrophotometry is used to determine the concentrations of individual components in a sample by measuring the selective absorption of light by gaseous molecules produced by spraying a solution into a fire or by evaporation in a carbon tube. AAS utilizes the absorption of light to Determine the concentration of certain metallic atoms in a liquid or solid by vaporizing the sample in a fire FAAS or graphite furnace GFAAS. The ground state free metal atoms are excited by a particular wavelength of light, together with the amount of energy consumed proportional to the number of atoms of the element in the sample. The gap between the sample and the background absorption is then measured, and compared with the absorption of a set of standard solutions.
AAS Is Often used for trace metal Analysis of a wide selection of sample types from the environmental sciences, food and beverage, pharmaceutical and chemical industries for impurity or contamination monitoring and quality management, in addition to the rapid assessment of raw materials. Additionally, it is utilized in a clinical setting for the analysis of biological fluids, such as urine and blood. The primary advantages of AAS are that It is relatively inexpensive and simple to use, while still offering high throughput, quantitative analysis of the metal content of fluids or solids. That makes it convenient for use in a broad selection of applications. The atomic absorption spectroscopy is commonly used to determine the concentration of metals in solution in the parts per million ppm or parts per billion ppb ranges. The metal ions are nebulized as a fine spray into a high temperature fire where they are reduced to their atoms which selectively absorb light from an element-specific hollow cathode lamp.
The primary disadvantages of the technique are its limited sensitivity, its ability to only measure 1 component at a time and restricted linearity. Despite these variables it has proved a great, robust technique for regular mental determinations. GFAAS is a More sensitive method typically employed for the detection of very low levels of compounds in low volume samples. A narrow carbon tubing is used to atomize the sample rather than a flame, improving the sensitivity and limit of detection from the lack of spectral noise in the fire and making sure that much more of this sample is atomized. The high sensitivity of AAS Techniques means it is essential that the water used to prepare blanks, standards and samples is free of contaminants which could affect the accuracy and reliability of the results. This is especially true for GFAAS, which has detection limits at sub- ppb levels, which makes it crucial that all water used throughout the analytical workflow is free of any elements or chemicals that may interfere with the results.