Horseshoe Crab Blood

Horseshoe crabs use hemocyanin to carry oxygen through their blood. Because of the copper present in hemocyanin, their blood is blue. ... Amebocytes from the blood of L. polymus are used to make Limulus amebocyte lysate (LAL), which is used for the detection of bacterial endoical applications.Their distinctive blue blood is used to detect dangerous Gram-negative bacteria such as E. coli in injectable drugs such as insulin, implantable medical devices such as knee replacements, and hospital instruments such as scalpels and IVs. Components of this crab blood have a unique and invaluable talent for finding infection, and that has driven up an insatiable demand. Every year the medical testing industry catches a half-million horseshoe crabs to sample their blood.