Whitepaper: Analytical criteria in bacterial endotoxin testing using LAL and rFC

This article covers the analytical criteria that apply to Bacterial Endotoxin Testing (BET) using Limulus Amebocyte Lysate (LAL) or recombinant Horseshoe crab Factor C (rFC) for the bioactivity determination of endotoxin in aqueous solutions, such as pharmaceuticals and medical device extracts. It explains the importance of these criteria for accurate analysis; hence, their understanding can ultimately facilitate robust BET and in turn keep patients safe from endotoxin.

A part from gel clot LAL tests, BET is purely quantitative; ie, the endotoxin activity is returned as defined, indiscreet endotoxin units (EU; also known as international units, IU). Since liquids are analysed, activities are commonly converted into concentrations – eg, EU/mL – and in turn to other units of measurement, eg, EU/mg. The different BET methods are subject to a) compendial criteria and b) test-dependent criteria as developed by reagent manufacturers; criteria meant to guarantee robust test performance.