Development And Validation of Stability-Indicating RP-HPLC And LC-MS/MS Methods For Quantification of Eltrombopag Olamine and Carbidopa-Levodopa Impurities

Robust and sensitive analytical methods were developed and validated for the simultaneous quantification of Eltrombopag Olamine (ELO) and its related impurities, alongside Carbidopa and Levodopa impurities in pharmaceutical formulations. An RP-HPLC method employing a Cosmisil Phenyl-Hexyl column was optimized for ELO and its contaminants, while an LC-MS/MS method was established for the nitrosamine impurity N,N-bis(2-hydroxyethyl)nitrous amide (NDELA) quantification. For Carbidopa and Levodopa impurities, an RP-HPLC method using a Kromasil column was developed. Method optimization utilized a Quality by Design (QbD) approach with factorial design experiments to ensure robustness. Validation parameters, including specificity, linearity, accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ), complied with ICH guidelines. Forced degradation studies confirmed the stability-indicating nature of the methods. The validated techniques demonstrated high sensitivity, specificity, and reproducibility, making them suitable for routine quality control and stability testing of pharmaceutical products containing ELO, Carbidopa, and Levodopa.