Limulus Amebocyte Lysate (LAL) is a substance derived from the blood of the horseshoe crab. It is primarily used in laboratories to detect bacterial contamination in medical equipment and pharmaceuticals. LAL reacts with bacterial endotoxins, producing a gel-like substance, which indicates the presence of harmful bacteria. The use of LAL is crucial for ensuring the safety of injectable drugs and medical devices. Because it is highly sensitive to endotoxins, it serves as a reliable test to prevent infections in patients. This makes LAL an essential tool in the fields of medicine and biotechnology.