Q:

When preparing to run a Lonza Bacterial Endotoxin Test (BET), LAL or PyroGene™ Recombinant Factor C (rFC), endotoxin detection kit how is the potency of CSE determined?

A:

The RSE/CSE procedure used by Lonza to determine CSE potency is found on the Certificate of Analysis for each matched kit. In general, dilutions of endotoxin from multiple vials of CSE are tested unknowns compared to a series of standards produced with RSE. The results from the CSE dilutions are calculated compared to the results of the RSE to yeild potencies in EU/ml. For the gel clot method, the geometric mean of the dilution that yielded the endpoints of the vials tested is multiplied by the sensitivity of the lysate to determine the potency in EU/ml. For quantitative methods, dilutions with results that fall within the tested RSE standard curve range are averaged to determine the potency in EU/ml. To calculate potency per ng, the potency is multiplied by the volume used to reconstitute the CSE (for example, 5 ml) and the appropriate ng of endotoxin lyophilized in each vial. This yields EU/ng.

Categories:
Endotoxin Detection
Research Areas:
Endotoxin Testing