About Analytical and Technological Reasons of Out-of-Specification Results for Assay and Disolution Tests (Review)

Abstract

Introduction. Out of specification (OOS) results represent a major challenge in the development, validation and use of the Assay and Dissolution methods. The topic is relevant, which is confirmed by Internet search data for the phrase "Out-of-Specification" + "HPLC" – about 35,300 results were found.Text. The analytical and technological reasons (factors) that can lead to underestimated or overestimated test results are considered and systematized in the form of a summary table important for practice. These are the following factors. Factors associated with the calculation formula. Factors related to the preparation of samples. Factors related to the sample solvent and ratio of the pH the sample solution and the mobile phase. Factors associated with chromatograms and their processing. The main technological factors.Conclusion. Data and recommendations are presented to search for analytical and technological reasons for obtaining Out-of-Specification results in the case of tests Assay and Dissolution.