title: Improved LC of minocycline drug substance.
abstract: An isocratic liquid chromatographic method is described for the separation of minocycline and its impurities. This method uses XTerra RP-18, 5 microm (25 cm x 4.6 mm I.D.), a silica-based stationary phase with reduced silanol activity. A mobile phase composed of acetonitrile-0.2 M tetrabutylammonium hydrogen sulphate pH 6.5-0.2 M ethylenediaminetetraacetic acid pH 6.5-water (20:20:20:40; v/v/v/v) was used at a flow rate of 1 ml/min. The column temperature was set at 35 degrees C. UV detection was performed at 280 nm. Optimisation of the separation method and a robustness study were performed by means of a central composite experimental design. The method allows to separate minocycline from known impurities. Some unidentified impurities are also separated. The total time of analysis is less than 20 min.
authors.affiliation: National Organization for Drug Control and Research, Cairo, Egypt.
authors.forename: N H
authors.initials: NH
authors.lastname: Zawilla
authors.forename: J
authors.initials: J
authors.lastname: Diana
authors.forename: J
authors.initials: J
authors.lastname: Hoogmartens
authors.forename: E
authors.initials: E
authors.lastname: Adams
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods; D008911:Minocycline / Q000032:analysis*; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000900:Anti-Bacterial Agents; D008911:Minocycline