Epirubicin is an anthracycline chemotherapy drug used for the treatment of various types of cancer. However, during the manufacturing process of epirubicin, impurities can be formed. These impurities can affect the safety, quality, and efficacy of the drug. Therefore, it is important to monitor and control the levels of these impurities in epirubicin formulations. Common impurities include epimer B, epirubicinone, and 13-dihydroxyep