Trace element analysis holds significant value for scientists as well as manufacturers in different industries. Whether it is about analyzing the purity of a substance or detecting its composition, ICP-MS and ICP-OES are most widely used along with Atomic Absorption Spectrometry. Both ICP-OES and ICP MS instruments are widely used for trace element analysis. ICP-MS measures an atom’s mass by mass spectrometry; however, ICP-OES quantification measures the excited atoms and ions at the wavelength characteristics for the specific element measured. Choosing between the two depends on the following parameters:
Characteristics of the chosen environmental sample
The ICP MS instruments are used to measure samples with low regulatory limits as they have a much lower tolerance for TDS. On the other hand, ICP-OES is primarily used to analyze samples with high total dissolved solids or suspended solids. ICP OES is thus more effective for analyzing wastewater soil, groundwater, and solid waste.
ICP-OES can hence be used for drinking water analysis, but typically it is used to measure the contaminants for environmental safety assessment. In addition, as both ICP OES and ICP MS can be used for high matrix samples, the sample dilution procedure is often essential in ICP MS. If a sample has analytes of the great difference in their concentration, ICP MS can possess a wider dynamic linear range which makes dilution and detection tough.
The prime advantage of ICP MS
ICP MS is mainly used as the workhorse for metal analysis in water. The ICP MS instrument is used for a wide range of environmental applications in wide dynamic range, isotopic analysis, rapid semi-quantitative analysis, efficiently removing polyatomic spectral interferences using collision cell technology, and much more.
Nevertheless, ICP MS has a great sensitivity advantage over the other optical techniques such as AAS as well as ICP-OES because of its greater dynamic range. The only major drawback is that the lead sample matrix can suppress the element signals and reduce the ion throughput to yield erratic results. This limitation can be avoided by precipitation the lead with sulfuric acid.
Significance of ICP OES
On the other hand, ICP OES is mostly used for all the matrices of environmental samples. Mostly the technique is used for high-matrix samples to analyze a wide range of environmental samples. In ICP-OES, analytical grade reagents are sufficient. It is a relatively simpler method of development and hence it does not need a specialist with highly technical expertise. Overall, the process of ICP-OES is much cheaper than ICP MS and it does not need a lower detection limit than the ICP MS process delivers.
The bottom line
Undoubtedly both the processes are different in their principle as well as practical applications. However, both of them are extensively used in the industry by laboratorial as well as analytical fields by the experts. Starting from the environmental and pharmaceutical analysis to food processing, ICP-MS and ICP-OES are used for a myriad of reasons. Before selecting a method go through the pros and cons of each thoroughly and decide which one will suit your need and why.