Analysis of tetracycline antibiotics and their common impurities by high-performance liquid chromatography using a polymeric column.

The chromatographic separation of tetracycline, oxytetracycline, 6-demethyl-chlortetracycline, methacycline and minocycline, and the common impurities of tetracycline, oxytetracycline and chlortetracycline has been optimised on a Hamilton PRP-1 column using citrate-phosphate buffer with propan-2-ol and tetrahydrofuran as organic modifiers. Column efficiency was approximately doubled by the inclusion of 1% v/v dichloromethane in the mobile phase.