Antimicrobial Effectiveness Testing (AET), also known as preservative efficacy testing or USP <51>, is a standardized laboratory method used to measure how well a product’s preservative system kills or inhibits microorganisms over a 28-day period.
The test is particularly relevant for multidose and preserved pharmaceutical preparations, where repeated use can introduce microorganisms into the product.
The test is also commonly referred to as Preservative Effectiveness Testing (PET). It helps demonstrate that the preservative system can provide appropriate microbiological protection throughout the relevant product lifecycle and use conditions.
๐๐ซ๐ข๐ง๐๐ข๐ฉ๐ฅ๐ ๐จ๐ ๐๐๐
The basic principle involves deliberately introducing specified microorganisms into the test product and monitoring their numbers over defined time intervals.The general concept is:
Inoculate โ Incubate โ Recover โ Count โ Compare with Acceptance Criteria
If the preservative system is effective, the microorganisms should show the required reduction or controlled growth pattern specified by the applicable compendial method.
๐๐ก๐ฒ ๐๐ฌ ๐๐๐ ๐๐ฆ๐ฉ๐จ๐ซ๐ญ๐๐ง๐ญ?
An effective preservative system can help control microorganisms that may enter the product.
AET helps pharmaceutical manufacturers:
- Evaluate preservative performance
- Support microbiological quality of preserved products
- Identify inadequate preservative systems
- Support formulation development
- Verify microbiological protection under the applicable test conditions
- Reduce the risk associated with microbial proliferation
๐๐จ๐ฐ ๐ข๐ฌ ๐ญ๐ก๐ ๐๐ง๐ญ๐ข๐ฆ๐ข๐๐ซ๐จ๐๐ข๐๐ฅ ๐๐๐๐๐๐ญ๐ข๐ฏ๐๐ง๐๐ฌ๐ฌ ๐๐๐ฌ๐ญ ๐๐๐ซ๐๐จ๐ซ๐ฆ๐๐?
The steps involved in antimicrobial effectiveness testingare:
- Selection of Microorganisms
- Inoculation of the Product
- Incubation and Sampling
- Analysis of Results
