Significance and Use
The antimicrobial activity of a substrate-bound antimicrobial is dependent upon direct contact of microbes with the active chemical agent. This test determines the antimicrobial activity of treated specimen by shaking samples of surface bound materials in a concentrated bacterial suspension for a one hour contact time or other contact times as specified by the investigator. The suspension is serially diluted both . before and after contact and cultured. The number of viable organisms in the suspension is determined and the percent reduction is calculated based on initial counts or on retrievals from appropriate untreated controls.
Note 2—This method is intended for those surfaces having a percent reduction activity of 50 % to 100 % for the specified contact time.
1.1 This test method is designed to evaluate the resistance of non-leaching antimicrobial treated specimens to the growth of microbes under dynamic contact conditions. This dynamic shake flask test was developed for routine quality control and screening tests in order to overcome difficulties in using classical antimicrobial test methods to evaluate substrate-bound antimicrobials. These difficulties include ensuring contact of inoculum to treated surface (as in AATCC 100), flexibility of retrieval at different contact times, use of inappropriately applied static conditions (as in AATCC 147), sensitivity, and reproducibility. This test also allows for the versatility of testing contamination due to such things as hard water, proteins, blood, serum, various chemicals, and other contaminates or physical/chemical stresses or manipulations of the specimens of interest.
1.2 Surface antimicrobial activity is determined by comparing results from the test sample to simultaneously run controls.
1.3 The presence of a leaching antimicrobial is both pre- and post-determined by the presence of a zone of inhibition.
1.4 This test method should be performed only by those trained in microbiological techniques.
1.5 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.