Endotoxin testing by LAL assay

What an endotoxin test answers

Endotoxins are fragments of the outer membrane of gram-negative bacteria. They are heat-stable and outlast the bacteria that shed them, so a sample can contain no living organisms and still carry endotoxin. Sterility and endotoxin are different questions, and a clean answer to one says nothing about the other.

How we run it

Endotoxin is measured with a kinetic chromogenic Limulus Amebocyte Lysate (LAL) assay and reported in endotoxin units per milligram (EU/mg), so the figure scales with the amount of material rather than the volume it happens to be dissolved in.

What the certificate reports

• Endotoxin in EU/mg
• Method and the named analyst
• A COA number anyone can check at Verify a COA

How to order

1. Create a free account. Individual or business; an individual account needs only an email address.
2. Build the order and submit it. One row per sample. Choose a package that includes endotoxins, or add it to any sample.
3. Get your chain-of-custody form and payment link. Both are emailed the moment you submit and saved on the order in your account.
4. Post the vials. Write each Sample ID on its vial and on the package, and add your tracking number to the order.

Sample requirements

For lyophilized powder, 2 mg or more per vial is ideal; we can usually work with less and will tell you before we start if the amount is marginal. For reconstituted solution, send at least 0.5 mL. This test is subdivided from the same vial as the sample’s other tests. Pro 7X takes two vials of the same sample, because it includes sterility.