Minimum inhibitory concentration

[3][4] The MIC is determined by preparing a dilution series of the chemical, adding agar or broth, then inoculating with bacteria or fungi, and incubating at a suitable temperature.

The value obtained is largely dependent on the susceptibility of the microorganism and the antimicrobial potency of the chemical, but other variables can affect results too.

The first step in drug discovery is often measurement of the MICs of biological extracts, isolated compounds or large chemical libraries against bacteria and fungi of interest.

[13] The protocols and parameters set by the CLSI are considered to be the "gold standard" in the United States and are used by regulatory authorities, such as the FDA, to make evaluations.

[16] The MIC is determined in such cases by growing the pathogen isolate from the patient on plate or broth, which is later used in the assay.

[18] Usage of incompatible levels of antimicrobials provides the selective pressure that has driven the direction and evolution of resistance of bacterial pathogens.

For verification, the positive control is plated in a hundred fold dilution to count colony forming units.

[21] Etests can be used as an alternative method to determine the minimum inhibitory concentrations of a wide range of antimicrobial agents against different organisms.

Manufactured by bioMérieux, Etests are a ready-to-use, non-porous plastic reagent strip with a predefined gradient of antibiotic, covering a continuous concentration range.

[13] In addition, drug effectiveness is generally similar when taken at both MIC and MBC concentrations because the host immune system can expel the pathogen when bacterial proliferation is at a standstill.

Mutating Bacteria poses a higher risk to humans more than ever and thus MIC Test is important to ensure we are one step ahead of them.