Limulus Lysate LAL

Bacteria also produce toxins which have traditionally been tested by the use of 

The horseshoe crab Ldmulus) suffers from a disease caused by the genus Vibrio which causes fatal intravascular clotting. This observation led to the realisation that the amoebocytes collected from the haemolymph of the crab contained a reactive protein (known as LAL), which could be released by lysis in distilled water. The LAL reagent is specific for the endotoxin of Gram-negative bacteria. This endotoxin is the lipopolysaccharide (LPS) fraction, and it is the lipid portion which reacts with LAL. 

Problems may arise as the LAL from different manufacturers is variable and also the LPS from different Gram-negative bacteria does not produce an equal 

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