The Antimicrobial Effectiveness Test (AET)—historically called the preservative effectiveness test—is performed to demonstrate if added preservatives, or the inherent antimicrobial properties of a product, are effective.

Antimicrobial effectiveness testing is required for all multidose products and single dose products with added preservatives. Pace Analytical Life Sciences has methods in place that meet the requirements for the AET test and the recovery method suitability required by USP <51>.

During the test, aliquots of the product are inoculated with the five challenge organisms defined in USP <51> at high populations. The samples are stored at 20-25°C for 28 days and are analyzed periodically to determine the change in challenge organism population. Additional challenge organisms can be used at the client’s request.

Testing to meet the requirements of European Pharmacopoeia (EP) and re-challenge studies, in which the sample is inoculated multiple times, can also be performed. Pace Analytical Life Sciences has experience with a wide range of product types including parenteral, oral and topical products.

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Chelsea Robinson Marketing Manager, Pace Analytical Life Sciences