How to Choose the Appropriate Endotoxin Detection Method

2025-11-12

Question: BETMAT's endotoxin detection kits come in different types, including natural Limulus Amebocyte Lysate (LAL) reagents and recombinant endotoxin assay reagents like recombinant Factor C (rFC) and recombinant Cascade Reagents (rCR). Which type of reagent should be chosen?

Answer: The appropriate detection method should be selected based on the user's detection frequency and detection requirements. If you only need to detect the endotoxin content of a few samples, you can consider BETMAT's endotoxin testing service. If endotoxin detection is only required for a certain period of time, the gel-clot method or end-point chromogenic method can be adopted. This is because these two methods do not require specialized endotoxin detection equipment. The gel-clot method can only provide qualitative or semi-quantitative detection results. If you have a spectrophotometer or a microplate reader equipped with a 405nm filter, the end-point chromogenic method can be used for accurate quantification.
If regular endotoxin detection is required, the following methods are available for selection:

- The gel-clot method can detect whether the endotoxin content exceeds the limit specified by regulations, but it cannot determine the exact endotoxin content in the sample.

- If you need to know the exact endotoxin content in the sample or understand the dynamic changes of endotoxin levels during the production process, quantitative detection methods such as the kinetic turbidimetric method, kinetic chromogenic method, rFC (recombinant Factor C) method, or rCR (recombinant Cascade Reagents) method can be used.

For detecting samples such as water, dialysate, and medical devices—samples that cause relatively little interference to endotoxin detection—the kinetic turbidimetric method, kinetic chromogenic method, rFC method, and rCR method can be used.

For detecting biological products such as vaccines, protein samples, and blood products—samples that may cause significant interference to endotoxin detection—the samples need to be treated by methods such as dilution, and detection reagents with high sensitivity should be used. The kinetic chromogenic method, rCR method, and other detection methods with high sensitivity are recommended.

For samples that may contain glucan, the rFC method and rCR method can be used for detection. These reagents do not contain the G-factor pathway and are not interfered by glucan. Alternatively, endotoxin-specific LAL reagents can be used for detection.