ASTM E2149-20. Standard test method for determining the antimicrobial activity of immobilized antimicrobial agents under dynamic contact conditions.
Test accredited by ENAC (Spanish National Accreditation Entity).
The method according to ASTM E2149 standard is designed to determine the antimicrobial activity of substances with antimicrobial activity bound immobilized and not liberated, under dynamic conditions. This is the only method that can determine such activity in irregular surfaces. For objects with flat surfaces, it is recommended to follow the JIS Z 2801 or ISO 22196 standards. If the antimicrobial is liberate from the surface, JIS Z 2801 or ASTM E2180 method should be used. The test microorganism is adjusted to a certain concentration in a suspension inside flasks. Three parallel tests are performed: the object to be testes with the bacterial suspension, and a control object without antimicrobial, along with the bacterial suspension must be made to include single bacterial suspension. The test counts are performed at times 0, and after stirring for a period of time. After the contact period the microorganisms count, compared with the counts in the other flasks used without the test article and control should be performed. The test object is considered to have antimicrobial effect if significantly reduces the number of microorganisms in the suspension, relative to the number of microorganisms present in the control culture, and culturing a control object without antimicrobial. It must be shown that the antimicrobial has not been released from the test object because if it occurs, the test is invalid, so if there should be quantified antimicrobial release with the corresponding test.