title: Analysis of unknown compounds in azithromycin bulk samples with liquid chromatography coupled to ion trap mass spectrometry.
abstract: A selective reversed-phase liquid chromatography/mass spectrometry (LC/MS(n)) method is described for the identification of azithromycin impurities and related substances in commercial azithromycin samples. Mass spectral data are acquired on an LCQ ion trap mass spectrometer equipped with an atmospheric pressure chemical ionization interface operated in positive ion mode. The LCQ provides on-line LC/MS(n) capability, making it ideally suited for identification purposes. In comparison with UV detection, this hyphenated technique provides as its main advantage efficient identification of novel substances without time-consuming isolation and purification procedures. Using this technique, six novel related substances detected in commercial azithromycin samples have been studied.
authors.affiliation: Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Debremaeker
authors.forename: D
authors.initials: D
authors.lastname: Visky
authors.forename: H K
authors.initials: HK
authors.lastname: Chepkwony
authors.forename: A
authors.initials: A
authors.lastname: Van Schepdael
authors.forename: E
authors.initials: E
authors.lastname: Roets
authors.forename: J
authors.initials: J
authors.lastname: Hoogmartens
mesh_terms: D000900:Anti-Bacterial Agents; D017963:Azithromycin; D002853:Chromatography, Liquid / Q000379:methods*; D004340:Drug Contamination; D013058:Mass Spectrometry / Q000379:methods*; D015394:Molecular Structure; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D012015:Reference Standards
chemical_list: D000900:Anti-Bacterial Agents; D004364:Pharmaceutical Preparations; D017963:Azithromycin