Endotoxins are lipopolysaccharides (LPS) shed by Gram-negative bacteria. They are heat-stable and active at very low concentrations, and in cell culture they can trigger responses that are mistaken for an effect of the material under study.
They are measured with the limulus amebocyte lysate (LAL) assay or recombinant factor C methods and reported in endotoxin units (EU) per milligram or per millilitre.
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For in vitro laboratory research only. Not for human or veterinary use. This library describes chemistry, analytical methods and published laboratory research; it gives no guidance on use in people or animals.