TLC separation of certain tetracycline and amino glycopeptide antibiotics

The separation of tetracycline and amino glycopeptide antibiotics was achieved on silica gel thin layers. Tetracycline antibiotics were resolved on a Co+2 (1.0%) impregnated silica gel layer using ethanol:acetic acid:water (10:6:6, v/v/v) as the mobile phase. Amino glycopeptide antibiotics were separated on an untreated silica gel layer using the mobile phase n-butanol:formic acid:water (6:5:7, v/v/v). The spots of these antibiotics were located by exposing the chromatoplate to iodine vapours.