title: Photochemical degradation of solid-state nisoldipine monitored by HPLC.
abstract: The photochemical degradation of solid-state nisoldipine, 1,4-dihydropyridine calcium antagonist, was investigated under daylight and UV light conditions. Degradation products were identified by using the retention times of corresponding standards and quantified by high-performance liquid chromatographic method. The daylight illumination induced appearance of nitrosophenylpyridine, while formation of second degradation product, nitrophenylpyridine, was observed only upon UV light illumination. The photodegradation kinetics of solid-state nisoldipine under daylight and UV light illumination belongs to class of zero-order reactions. The rate constants of disappearance of nisoldipine upon illumination were determined for raw material as well as pharmaceuticals (tablets, film-tablets and capsules).
authors.affiliation: Zdravlje Pharmaceutical and Chemical Industry, Quality Control Sector, 16000 Leskovac, Serbia and Montenegro, Yugoslavia.
authors.forename: Valentina D
authors.initials: VD
authors.lastname: Marinkovic
authors.forename: Danica
authors.initials: D
authors.lastname: Agbaba
authors.forename: Katarina
authors.initials: K
authors.lastname: Karljikovic-Rajic
authors.forename: Sote
authors.initials: S
authors.lastname: Vladimirov
authors.forename: Jovan M
authors.initials: JM
authors.lastname: Nedeljkovic
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D008027:Light / Q000009:adverse effects*; D015737:Nisoldipine / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism*; D010777:Photochemistry; D013678:Technology, Pharmaceutical / Q000379:methods*; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D015737:Nisoldipine