ε-Biotinamidocaproyl-β-alanyl-β-alanyl-lisinopril is an angiotensin-converting enzyme ( ACE ) inhibitor. Structurally, ε-Biotinamidocaproyl-β-alanyl-β-alanyl-lisinopril is a biotinylated derivative of lisinopril , with a chemical structure linking the biotin molecule and the lisinopril molecule composed of 19 atoms. ε-Biotinamidocaproyl-β-alanyl-β-alanyl-lisinopril can bind to both ACE and streptavidin simultaneously, making it possible to separate and purify ACE using streptavidin-agarose beads.