Development and Validation of a Stability-indicating UPLC-DAD Method for the Simultaneous Determination of Ivermectin...

Currently, there is no single rapid and accurate stability-indicating quantitative method that can simultaneously determine both ivermectin and praziquantel and their related compounds. Thus, the goal of this research is to develop and validate a new rapid, accurate, and stability-indicating ultra-performance liquid chromatography (UPLC) method. The method uses a water, acetonitrile, and methanol gradient. The chromatographic separation was achieved on a C18 (1.7 μm, 2.1 × 50 mm) column with a flow rate of 0.7 mL/min, and the column temperature was maintained at 40°C. Analytes are detected at 245 nm. The method was validated in accordance with ICH Q2R1 guidelines. The linearity (R²) was >0.9987 and 0.9997 for praziquantel and ivermectin, respectively. The corresponding accuracy ranged between 98.0 and 102.0%. Intermediate precision (assessed as inter-day precision) was determined by calculating the cumulative %CV of eighteen assay preparations and was less than 2.0% for both praziquantel and ivermectin. The specificity of the method was shown by the resolution of the two active pharmaceutical ingredients (APIs) from any interfering excipients, impurities, or degradation products. The limit of detection and quantitation for ivermectin was 26.80 ng/mL and 81.22 ng/mL, respectively. The limit of detection and quantitation for praziquantel was 1.39 μg/mL and 4.22 μg/mL, respectively. The robustness study proved that method performance is stable against small variations in sample processing parameters (shaking, sonication time, and acetonitrile % in solvent solution) and also against small variations in the initial % of mobile phase components and gradient slope. Using ICH Q2R2 criteria, the method was demonstrated to be specific, accurate, stability indicating, and robust to small variations of chromatographic variables.