Atomic emission spectroscopy (AES) is a technique used to identify and quantify elements in a sample by measuring the intensity of their emitted light. AES can be used for qualitative, semi-quantitative, and quantitative analysis depending on the measurement parameters and calibration standards used.
Qualitative Analysis: In qualitative analysis, AES is used to determine which elements are present in a sample without measuring their concentration. The characteristic wavelengths of the elements emitted from the plasma are compared to known atomic spectra to identify the elements present in the sample.
Semi-Quantitative Analysis: Semi-quantitative analysis involves estimating the relative amounts of different elements present in a sample based on the intensity of their emitted light. This method assumes that there is a linear relationship between the intensity of an element’s emission line and its concentration. A calibration curve is constructed using standard samples with known concentrations of each element, and this curve is used to estimate the concentrations of unknown samples.
Quantitative Analysis: Quantitative analysis involves determining the exact concentration of each element in a sample. This method requires accurate calibration standards and careful control over variables such as plasma temperature, gas flow rates, and detector sensitivity. Calibration curves are constructed using standard samples with known concentrations of each element, and these curves are used to calculate the concentration of unknown samples.
The accuracy and precision of quantitative analysis can be affected by several factors, including matrix effects from other components in the sample, spectral interferences from overlapping emission lines, and variations in instrument performance over time.
Overall, AES is a powerful tool for elemental analysis that can provide both qualitative and quantitative information about complex samples. Careful attention to measurement parameters and calibration standards can help ensure accurate results for a wide range of applications.
