title: Gradient RP-HPLC method for the determination of potential impurities in atazanavir sulfate.
abstract: This paper proposes a simple and selective RP-HPLC method for the determination of process impurities and degradation products (degradants) of atazanavir sulfate (ATV) drug substance. Chromatographic separation was achieved on Ascentis(®) Express C8, (150mm×4.6mm, 2.7μm) column thermostated at 30°C under gradient elution by a binary mixture of potassium dihydrogen phosphate (pH 3.5, 0.02M) and ACN at a flow rate of 1.0ml/min. A photodiode array (PDA) detector set at 250nm was used for detection. Stress testing (forced degradation) of ATV was carried out under acidic, alkaline, oxidative, photolytic, thermal and humidity conditions. In presence of alkali, ATV transformed into cyclized products and the order of degradation reaction is determined by the method of initial rates. The unknown process impurities and alkaline degradants are isolated by preparative LC and characterized by ESI-MS/MS, (1)H NMR, and FT-IR spectral data. The developed method is validated with respect to sensitivity (lod and loq), linearity, precision, accuracy and robustness and can be implemented for routine quality control analysis and stability testing of ATV.
authors.affiliation: APL Research Centre, Aurobindo Pharma Limited, Hyderabad, Andhra Pradesh, India.
authors.forename: Sreenivasa Rao
authors.initials: SR
authors.lastname: Chitturi
authors.forename: Yallappa Somappa
authors.initials: YS
authors.lastname: Somannavar
authors.forename: Badarinadh Gupta
authors.initials: BG
authors.lastname: Peruri
authors.forename: Sreenivas
authors.initials: S
authors.lastname: Nallapati
authors.forename: Hemant Kumar
authors.initials: HK
authors.lastname: Sharma
authors.forename: Shankar Reddy
authors.initials: SR
authors.lastname: Budidet
authors.forename: Vijay Kumar
authors.initials: VK
authors.lastname: Handa
authors.forename: Hima Bindu
authors.initials: HB
authors.lastname: Vurimindi
mesh_terms: D000069446:Atazanavir Sulfate; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D004355:Drug Stability; D017320:HIV Protease Inhibitors / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D057230:Limit of Detection; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D011786:Quality Control; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D017550:Spectroscopy, Fourier Transform Infrared; D053719:Tandem Mass Spectrometry; D013678:Technology, Pharmaceutical
chemical_list: D017320:HIV Protease Inhibitors; D009842:Oligopeptides; D011725:Pyridines; D000069446:Atazanavir Sulfate