Complete 5 pages APA formatted article: Validation Exercise in the Measurement of Iron. The process of method validation can be used when the method is new and has no previous performance history when an established method is proved to be changing with time when an established method is used in a different laboratory, with different analysts or with different equipment and also to demonstrate the equivalence between two methods.
The selectivity of a method refers to the extent to which it can determine particular analyte(s) in a complex mixture without interference from other components in the mixture while specificity generally refers to a method that provides a response for a single analyte only (McCormack, 1987). In selectivity, a number of chemical components may or may not be distinguished from each other while in specificity, only one component is distinguished from the rest.
In Atomic Absorption Spectroscopy, the absorbance of a single chemical component cannot be distinguished from that of a complex mixture. therefore, this method is not specific. For this method to work, the iron salt should not be contaminated with other ions therefore deionized water is used.
This expresses the degree of scattering between groups of measurements obtained from several samples of the same type under prescribed conditions. The higher the difference between values, the lower the precision and the lower the difference between values, the higher the range.
In the determination of the concentration of iron ions by atomic absorption spectroscopy, the overall range between the maximum and minimum values is the least making it the most precise method compared to the others. The least precise method is the colorimetric method since it has the highest overall range.
The accuracy of an analytical method is defined as the degree to which the determined value of analyte in a sample corresponds to a true value (Wismer, 1991). .