Analysis of Antibiotic Josamycin and Related Impurities on Zodiac HST TH Column

Josamycin is a macrolide antibiotic effective against gram-positive bacteria. Due to its high polarity, it exhibits poor retention on conventional reversed-phase columns. Mixed-mode chromatography using Zodiac HST TH was employed to effectively retain josamycin and its related impurities. Additionally, Zodiac HST RP was utilized to analyze josamycin impurities, offering the advantage of minimal retention of high-molecular-weight plasma components. This LC/MS-compatible method is also suitable for preparative chromatography and can be applied for the analysis of josamycin in various biofluids.