⚠️ Research Use Only. Not validated for clinical diagnostic use.
MPC Calculator
Mutant Prevention Concentration from agar dilution data. MPC/MIC ratio for resistance prevention.
Mutant Prevention Concentration
Enter dose (µg/mL) and CFU pairs from agar dilution, one per line. Also enter the initial CFU (no-drug control).
Results
MPC (µg/mL)
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MIC (µg/mL)
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MPC / MIC Ratio
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Understanding MPC
| Term | Definition |
|---|---|
| MPC | Lowest concentration preventing growth of the least susceptible single-step mutant (zero colonies). |
| MIC | Lowest concentration with ≤1% survival (visible growth inhibition). |
| MPC/MIC | Ratio indicating the mutant selection window. Lower = lower resistance risk. |
Frequently Asked Questions
What is MPC?
The Mutant Prevention Concentration is the lowest antibiotic concentration that prevents growth of the least susceptible single-step mutant.
What is MPC/MIC ratio?
A low MPC/MIC ratio suggests a narrower mutant selection window and lower resistance risk.
How is MPC different from MIC?
MIC inhibits visible growth of the bulk population. MPC prevents growth of resistant sub-populations (single-step mutants), so MPC ≥ MIC.