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

Josamycin is a macrolide antibiotic primarily active against gram-positive bacteria. Due to its high polarity, it exhibits poor retention on conventional reversed-phase columns. To address this, Zodiac HST TH, a mixed-mode column, was used to retain josamycin along with its related impurities. Additionally, Zodiac HST RP was employed for impurity profiling, as it effectively excludes high-molecular-weight plasma components, making it suitable for biological sample analysis. This method is fully compatible with LC/MS, preparative chromatography, and is ideal for the quantitative analysis of josamycin in biofluids.