Horseshoe crab blood is highly valuable because it contains a unique substance called Limulus Amebocyte Lysate (LAL), which is used in a test to detect bacterial endotoxins. This test, known as the ...

The blood contains a special clotting agent. It's used to make a concoction called Limulus amebocyte lysate or LAL. Before LAL, scientists had no easy way of knowing whether a vaccine or medical ...