Method Suitability Control Studies for Microbial Testing: Quantitative Comparisons

The measurement of microbial kill requires the ability to measure the number of surviving microorganisms with time after exposure to the antimicrobial agent. Bioburden determinations have the same requirement as they depend on the ability to recover viable microorganisms in the presence of potentially antimicrobial products or raw materials. However, carryover of residual disinfectant from the test could inhibit growth in the recovery medium, leading to poor microbial recovery. This potential residual activity must be neutralized and it is necessary to demonstrate the adequacy of neutralization for these tests (1-4). This demonstration of neutralization in compendial microbiological tests is known as demonstration of method suitability.