Doxycycline (hydrochloride) (Standard) is the analytical standard of Doxycycline (hydrochloride). This product is intended for research and analytical applications. Doxycycline hydrochloride, an antibiotic, is an orally active and broad-spectrum metalloproteinase (MMP) inhibitor[1]. Doxycycline hydrochloride shows antibacterial activity and anti-cancer cell proliferation activity[1][2][3][4][5].