IMPORTANCE OF THE VALIDATION OF ANALYTICAL METHODS
n any laboratory, the security of the results that an analysis provides is vital, because these results will serve as a basis for decision-making; For example, in a blood test, your results will be used for a medical diagnosis, in a quality laboratory, for the rejection or acceptance of a batch of material.
So to carry out an analysis, the laboratory staff must use an analytical method, which is actually a series of instructions, detailed techniques, that indicate how to carry out the analysis of a sample, the objective is to detect the presence or quantify the concentration of a particular substance called an analyte.
Some examples of analytes can be considered as: heavy metals in a raw material, glucose in the blood or lead in gasoline. Therefore, the reliability of the results of the analytical method depends essentially on three things:
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Well-trained analysts
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Suitable laboratory material and equipment
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And a valid analytic method
The latter refers to a method, a method that has already been tested and that has been shown to meet the required safety ranges. This test is called VALIDATION and consists of the determination of precisely validation parameters, depending on the type of analysis, some parameters are more relevant than others, among them the most representative are:
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Detection limit: Which is the smallest quantity of an analyte that the method can recognize.
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Quantification limit: As the smallest quantity of an analyte that the method can quantify, in other words, to measure.
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Repeatability: Is the method capacity to deliver concordant results (very similar) if the same sample is analyzed.
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Reproducibility: Is the method capacity to deliver concordant results when it is used in different laboratories (could be from different countries).
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Selectivity: Is the method capacity to “recognize” the analyte of interest and specifically measure it.
Third party laboratories, for example, have approved methods, hence, when there is a discrepancy about two results in the laboratories themselves, those are used, and their result is taken as the truth. For this reason, the DNP and Quality Control laboratories of ALTECSA constantly carry out work sessions, whose objective is: "To validate their analysis methods" in order to have the security and objectivity of the results that are published. And of course, give a solid base to the decisions made based on these results.