Use of dacron as an alternative carrier for evaluating oxidizing sterilants in the AOAC sporicidal test

The AOAC sporicidal method (966.04) recommends the use of porcelain penicyl inders and black waxed silk sutures as carriers for demonstrating the spori cidal activity of sterilants, However, the silk carriers are not suitable f or evaluating the sporicidal efficacy of oxidizing agents, and an inert pol yester material (Dacron) is recommended as an alternative. Dacron provides an equivalent microbial and physical challenge to silk. Microbiologically, both materials demonstrated similar HCI resistance, which is required by th e AOAC test, as well as equivalent spore loading and spore wash-off. Electr on microscopy showed that both materials present the same braided microstru cture, providing an equivalent physical challenge to the test sterilant. Da cron was more consistent than silk, and did not require extraction prior to spore loading. The extraction method for black waxed silk was variable and incomplete, which may compromise the activity of oxidizing sterilants and add to method variability. Silk was also structurally altered in the presen ce of oxidizing sterilants and increased sterilant degradation. Dacron did not affect the sterilant and was inert in the presence of oxidizing agents. Dacron sutures are proposed as inert alternatives to silk for evaluating t he sporicidal efficacy of oxidizing agents.