Stability Indicating UPLC Method for Quantifying Assay of Letrozole

Abstract

Letrozole, an aromatase inhibitor, is widely used in the treatment of hormone receptor-positive breast cancer. Ensuring the stability and accurate quantification of letrozole is crucial for its efficacy and safety in clinical practice. In this study, a stability indicating Ultra Performance Liquid Chromatography (UPLC) method was developed and validated for the quantitative determination of letrozole in pharmaceutical formulations. The UPLC method utilized a reverse-phase C18 column with a mobile phase consisting of acetonitrile and 0.1% formic acid in water, delivered in an isocratic mode at a flow rate of 0.5 mL/min. Detection was performed at a wavelength of 240 nm. The method exhibited excellent linearity over the concentration range of 5-100 μg/mL (r2 = 0.999), with a limit of detection (LOD) of 1 μg/mL and a limit of quantification (LOQ) of 5 μg/mL. The stability indicating capability of the method was demonstrated through forced degradation studies under various stress conditions, including acidic, basic, oxidative, thermal, and photolytic stress. Letrozole remained stable under all stress conditions, with no significant degradation observed. Additionally, the method showed good selectivity, specificity, precision, accuracy, and robustness in the quantification of letrozole. Overall, the developed UPLC method provides a reliable and sensitive approach for the quantitative determination of letrozole in pharmaceutical formulations. Its stability indicating nature ensures the accurate assessment of letrozole stability and potency, thereby facilitating quality control and assurance in the production and use of letrozole-containing medications.

Keywords: Letrozole, Photolytic, Stress, Quantification, Pharmaceutical.