Comparison of approaches for assessing detection and quantitation limits in bioanalytical methods using HPLC for...

The limit of detection (LOD) and limit of quantification (LOQ) stand elements in the validation of analytical and bioanalytical methods as emphasized in numerous guidelines. Despite this, the absence of a universal protocol for establishing these limits has led to varied approaches among researchers and analysts in literature. In this work we present the latest graphical strategy of validation known as the uncertainty profile to assess the LOQ and LOD. Then, we conducted a comparative study of this approach with those based on accuracy profile and parameters of the calibration curve. We realize the uncertainty profile from the uncertainty parameter calculated from the tolerance interval. Furthermore, we provide a succinct overview of alternative methods for computing these limits. This includes the classical strategy based on statistical concepts and graphical one using the method of accuracy profile. In pursuit of this objective, these strategies are implemented in the same experimental results of an HPLC method dedicated for the determination of sotalol in plasma using atenolol as internal standard. The classical strategy based on statistical concepts provides underestimated values of LOD and LOQ. In the other side, the two graphical tools give a relevant and realistic assessment, and the values LOD and LOQ found by uncertainty and accuracy profiles are in the same order of magnitude, especially the method of uncertainty profile. It provides precise estimate of the measurement uncertainty. The graphical strategies of validation, uncertainty profile and accuracy profile, based on tolerance interval are a reliable alternative to the classic strategy, based on classical concepts, for assessment of LOD and LOQ.