Variability and Test Error with the LAL Assay

The Limulus amebocyte lysate (LAL) assay is the compendial test for the examination of bacterial endotoxin in pharmaceutical products (as described in USP chapter <85>), in-process material, and pharmaceutical grade water.

With any biological tests, measurements are susceptible to variations in analytical conditions. Here the LAL assay has a relatively high level of variability even for a biological assay. This variation derives from 3 principle sources: reagents, product, and method. This paper examines some of the reasons for LAL test variation, focusing on photometric methods (chromogenic and turbidimetric), and considers how variation can be assessed through good laboratory quality control.

To review a new paper by Tim Sandle that looks at the variations and reasons for test error with the LAL assay, see American Pharmaceutical Review.

Reference:

Sandle, T. (2014) Variability and Test Error with the LAL Assay, American Pharmaceutical Review, October 2014, pp1-5

Posted by Tim Sandle