title: Photodegradation and photostability-indication of mequitazine.
abstract: The photochemical behavior is investigated for mequitazine (MQ) illustrating possible mechanisms and photodegradation products formed. Accelerated photolysis is done for MQ under justified stress conditions by subjecting aqueous drug solutions to radiation for specified period of time. Synthesis of the main photodegradants, the sulfoxide, is achieved. Selective quantification of MQ, singly in bulk form, pharmaceutical formulations and/or in the presence of its photodegradants is demonstrated. The indication of stability has been undertaken under conditions likely to be expected at normal storage conditions using a simple colorimetric method based on oxidation of the intact phenothiazine drug by potassium iodate in acid medium to form a red colored product adequate for quantitative estimation of the studied drug.
authors.affiliation: Analytical Chemistry Department, Faculty of Pharmacy-Cairo University, Kasr El-Aini St, ET-11562, Cairo, Egypt. eamoety@hotmail.com
authors.forename: Ezzat M
authors.initials: EM
authors.lastname: Abdel-Moety
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Ibrahim
authors.forename: Mamdouh R
authors.initials: MR
authors.lastname: Rezk
mesh_terms: D003124:Colorimetry; D010640:Phenothiazines / Q000737:chemistry*; D010782:Photolysis
chemical_list: D010640:Phenothiazines; C033540:mequitazine sulfoxide; C006069:mequitazine