Incurred sample reanalysis: different evaluation approaches on data obtained for spironolactone and its active metabolite canrenone.

Background: The inherent reproducibility of a bioanalytical approach is usually sustained through incurred sample reanalysis (ISR). Questions relating to the number of ISRs, the right moment for performing reanalysis, the way of performing an appropriate statistical refinement of experimental data and actions to be taken in the case of failure are frequently raised.

Results: Data resulting from ISR following a bioequivalence study for spironolactone formulations are discussed.

Large volume injection of 1-octanol as sample diluent in reversed phase liquid chromatography: application in bioanalysis for assaying of indapamide in whole blood.

Large volume injection of samples in strong diluents immiscible with the mobile phases used in reversed phase liquid chromatography (RPLC) has been recently introduced in practice. In the present work, the potential of the technique has been evaluated for bioanalytical applications. The process consists of the liquid-liquid extraction of indapamide from whole blood into 1-octanol, followed by the direct injection from the organic layer into the LC.