title: Forced-degradation study of valdecoxib as bulk drug and in tablet formulation by HPTLC.
abstract: A stability-indicating forced-degradation study of valdecoxib was conducted using high performance thin layer chromatography (HPTLC). It was used to analyze valdecoxib as bulk drug and as tablets. Undegraded valdecoxib was eluted with a retardation factor, Rf, of 0.56. Valdecoxib was forcibly degraded by exposure to alkali, acid, oxidation, and light, the greatest degradation occurring under basic conditions. Base-degraded valdecoxib gave an additional peak with an Rf value of 0.76. The calibration curve was linear in the range of 0.2-1 microg/microL with a correlation coefficient of 0.9952. Complete validation was carried out for precision (inter-day, intra-day, repeatability), accuracy, and robustness. All the data were analyzed statistically. This HPTLC procedure shows the reliability needed for use as a stability-indicating method. It can quantify valdecoxib in bulk and in tablets and also resolves the degraded peak of valdecoxib. This method is also useful for studying the degradation pattern and degradation mechanism of valdecoxib.
authors.affiliation: College of Pharmacy, Sri Ramakrishna Institute of Paramedical Sciences, Coimbatore, Tamil Nadu, India. tkravi2004@yahoo.co.in
authors.forename: Thengungal Kochupappy
authors.initials: TK
authors.lastname: Ravi
authors.forename: Muruganathan
authors.initials: M
authors.lastname: Gandhimathi
authors.forename: Azhewar
authors.initials: A
authors.lastname: Suganthi
authors.forename: Sabitha
authors.initials: S
authors.lastname: Sarovar
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000737:chemistry; D002855:Chromatography, Thin Layer / Q000379:methods* / Q000706:statistics & numerical data; D004339:Drug Compounding; D004355:Drug Stability; D006801:Humans; D066298:In Vitro Techniques; D007555:Isoxazoles / Q000008:administration & dosage / Q000737:chemistry*; D013449:Sulfonamides / Q000008:administration & dosage / Q000737:chemistry*; D013607:Tablets; D000096926:Benzenesulfonamides
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007555:Isoxazoles; D013449:Sulfonamides; D013607:Tablets; C406224:valdecoxib; D000096926:Benzenesulfonamides