What are the two types of endotoxin testing?

• A. Rabbit pyrogen test; Endotoxin assay
• B. Rabbit pyrogen test; LAL test
• C. LAL test; Bacterial endotoxin assay
• D. Pyrogen test; Endotoxin quantitation

Answer: (B)

Endotoxin testing is carried out using both in vivo and in vitro approaches. The two main types are the Rabbit Pyrogen Test, an in vivo method that assesses fever response in rabbits after exposure to a sample, and the LAL test, an in vitro assay that uses horseshoe crab blood lysate to detect endotoxins. The Rabbit Pyrogen Test directly measures the biological fever response, which reflects any pyrogenic substances in the sample, but it is slower, requires animal use, and can be influenced by non-endotoxin pyrogens or product effects. The LAL test is highly sensitive and provides rapid, often quantitative results, making it the standard for routine endotoxin specification; however, it detects endotoxins specifically and may require careful sample preparation to avoid interference or masking by certain substances.