An Introduction to Bacterial Endotoxin Testing

Bacterial endotoxin testing (BET) is a fundamental safety requirement in the pharmaceutical and biomedical industries. If bacterial endotoxins enter patients’ bloodstream in sufficient concentrations, this can cause harmful symptoms such as fever and septic shock and can be fatal in the most severe cases. As such, any pharmaceutical products that will enter the body, including parenteral medicines and injectable devices, must be tested for the presence of endotoxins before release to the market. These quality control (QC) tests must comply with regulatory requirements enforced by the European and US Pharmacopoeia and US Food and Drug Administration (FDA). 

There are a variety of methods that can be used to detect bacterial endotoxins. A traditional qualitative approach is the rabbit pyrogen test (RPT), which was first developed in the early 1900s. The key principle is that parenteral drugs that are pyrogenic (i.e., contaminated with fever-inducing substances, including endotoxins, viruses, and moulds) induce temperature changes in rabbits. However, RPT is a generic pyrogen test and so is not specific to bacterial endotoxin.

In the following sections, we provide an overview of the LAL assay, including its importance in BET and how it enables the reliable and sensitive detection of bacterial endotoxins. We also outline the different methods of LAL testing that we offer, including the gel-clot test, turbidimetric and chromogenic assays, and the non-animal-derived recombinant Factor C (rFC) assay. This will help you choose the most suitable type of LAL testing method to meet the needs of your application.