DEVELOPMENT AND VALIDATION OF STABILITY INDICATING UPLC METHOD FOR THE SIMULTANEOUS ESTIMATION OF SERDEXMETHYLPHENIDATE AND DEXMETHYLPHENIDATE IN BULK AND THEIR COMBINED DOSAGE FORM Gaddey Pridhvi Krishna & Raja Sundararajan* Department of Pharmaceutical Analysis, GITAM Institute of Pharmacy, GITAM (Deemed to be University), Visakhapatnam, Pin code: 530 045, Andhra Pradesh (State), India *Corresponding author: Raja Sundararajan GITAM Institute of Pharmacy, GITAM (Deemed to be University), Visakhapatnam, Pincode: 530 045, Andhra Pradesh (State), India Mobile No: +91 9160508261 E-mail: sraja61@gmail.com Abstract A simple, precise, accurate and cost affective ultra-pressure liquid chromatographic technique was established for concurrent assessment of serdexmethylphenidate as well as dexmethylphenidate in pure drug and formulation. The process has shown acceptable separation of serdexmethylphenidate and dexmethylphenidate. The retention time for serdexmethylphenidate and dexmethylphenidate were 1.476 minutes and 1.806 minutes correspondingly. The drug formulation was exposed to basic, acidic, photolytic, thermal and hydrolysis stress environment. Consequently, stressed samples were analysed by means of projected analytical technique. Quantitation was achieved through ultra violet detection at 245 nm depending on peak area with linear calibration curve. The concentration ranges were 6.525-39.15 µg/ml for serdexmethylphenidate and 1.3-7.8 µg/ml for dexmethylphenidate. The LOD's were 0.17 µg/ml and 0.03 µg/ml for serdexmethylphenidate and dexmethylphenidate correspondingly. The LOQ's were 0.53 µg/ml for serdexmethylphenidate and 0.09 µg/ml for dexmethylphenidate. The projected technique was recognized to be precise and stability representing as there were not any intervening peaks of degradants and excipients. As a result, this intended approach was ideal for use in QC laboratories for quantitative analysis of both individual and mixed dosage forms of pharmaceuticals, as it was simple, quick, and precise. Keywords: UPLC, Serdexmethylphenidate, Dexmethylphenidate, Na2HPO4 YMER || ISSN : 0044-0477 VOLUME 21 : ISSUE 5 (May) - 2022 http://ymerdigital.com Page No:80