Journal of Chromatography A vol:829 issue:1-2 pages:161-166
A reversed-phase ion-pair liquid chromatographic method with UV detection at 210 nm is described for the separation of lincomycin from 7-epilincomycin and lincomycin B. The method utilizes a base-deactivated Supelcosil LC-ABZ, C12-18, 5 mu m, 250x4.6 mm I.D. column maintained at 45 degrees C. The mobile phase consists of 2.25% (v/v) acetonitrile, 5% (v/v) phosphate buffer (2.72%, m/v KH2PO4 adjusted to pH 5.0 with 3.48%, m/v K2HPO4), 0.067% (v/v) methanesulfonic acid and water to 100%. The flow-rate is 1.0 ml/min. The separation of lincomycin from 7-epilincomycin is only possible on base-deactivated (BDS) columns. Other octadecylsilyl columns examined showed insufficient selectivity. The method was also tested on other BDS columns (Spherisorb SS-ODS-B, 5 mu m, Hypersil BDS, C-18, 5 mu m and Supelcosil LC-ABZ, C-18, 5 mu m, all 250x4.6 mm I.D.) and showed good robustness. Robustness was further evaluated by performing a full-factorial design experiment. The method showed good selectivity, repeatability, linearity and sensitivity. It is also suitable for analysis of lincomycin formulations. (C) 1998 Elsevier Science B.V. All rights reserved.