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Antimicrobial Efficacy Testing

Tests to identify your molecules efficacy providing a broader portfolio of data to be used for development progression decisions.


Time-Kill Assays

A standard inoculum of the test organism is exposed to a known concentration, or a series of known concentrations of the test compound. At standard timepoints aliquots are removed and a cfu/mL bacterial count performed. This test identifies the activity of the antimicrobial (bactericidal or bacteriostatic) as well as identifying the rate of bacterial killing (if applicable)


Serial passage

Induction of bacterial resistance via exposure of the test organism to a doubling dilution concentration range of the test compound. The last concentration where growth is seen is then used to inoculate a new range. This process is repeated over a number of passages to see if the test organism readily evolves resistance to the test compound. Data on resistance development potential in this manner is useful as compounds to which resistance can be rapidly evolved may have a short shelf life in clinical utility.


Mutation frequency testing

Definition of the potential for single step mutations which confer resistance to the test compound to occur. To test this, a high concentration of bacterial inoculum is added to plates containing high levels of test compound (often x2, x4 and x8 MIC). Given the high concentration of the test organism which was added to the plates, if resistant mutants are likely to occur these will be cultured from the test plates. These can then be tested for robustness and survivability. This provides information on the chance that a single step resistant mutant may evolve against the test compound, as well as providing a useful resistant strain for further testing.


To discuss your project with our team of specialists or to find out more, please contact us