Antimicrobial Testing (Dynamic)
ASTM E2149-13a is a test method for determining the antimicrobial efficacy of antimicrobial agents under dynamic contact conditions. It is a sensitive shake flask test recommended for testing materials such as fabric, paper, powder and granular material. It evaluates the activity of an antimicrobial additive within non-leaching materials when shaken within an inoculated suspension. The number of viable organisms from the suspension is determined and the percentage reduction is calculated by comparing recovery from appropriate control samples, that have not been treated with antimicrobial additives.
The ASTM E2149-13A procedure
For each product to be tested according to ASTM E2149-13a, three sterile containers are needed; one containing only the bacterial suspension, one containing the treated article in the bacterial suspension and another flask containing an untreated article, or control, also in the bacterial suspension.
For the ASTM E2149-13A method, Escherichia coli ATCC 25922 is specified as the standard organism. Nevertheless, additional organisms can be requested, as well as modifications from the standard 1-hour contact time to 24 hours, or other time periods as required.
Things to note
Credibility of result
ASTM E2149-13a is a reproducible method that also allows experimental flexibility to test products of several shapes and sizes, generally consisting of treated fabrics. Routine quality controls on media are also carried out to maintain efficacy and accuracy of results.