NOVEL, SIMPLE ROBUST ISOCRATIC METHOD DEVELOPMENT AND VALIDATION FOR ESTIMATION OF MAROPITANT CITRATE AND METACRESOL TABLET AND LIQUID PHARMACEUTICAL DOSAGE FORM BY USING RP HPLC WITH UV/PDA DETECTOR

Maropitant citrate and Metacresol are widely used in veterinary and pharmaceutical formulations. Reliable analytical methods are essential for simultaneous estimation across diverse dosage forms to ensure quality, safety, and efficacy. To develop and validate a novel, simple, and robust isocratic RP‑HPLC method for the simultaneous quantification of Maropitant citrate and Metacresol in injectable, gel, syrup, and tablet formulations. Chromatographic separation was achieved using a Baker Bond C8 column (250 × 4.6 mm, 5 µm) at 40 °C with an isocratic mobile phase of monobasic phosphate buffer and acetonitrile (70:30 %v/v), at a flow rate of 1.0 mL/min. Detection was performed at 220 nm using a UV/PDA detector. Metacresol eluted at ~3.8 minutes and Maropitant at ~6 minutes, with no interference at analyte retention times. The calibration curve showed excellent linearity (r² = 0.999) across 50–150% concentration range. Recovery values (97–103%) confirmed accuracy. Precision, intermediate precision, and robustness studies demonstrated reproducibility, with system suitability parameters unaffected by minor variations. The developed RP‑HPLC method is novel, accurate, precise, and robust. It is suitable for routine quality control and regulatory analysis of Maropitant citrate and Metacresol in multiple pharmaceutical dosage forms.