AST is typically conducted using various methods, including:
Disk Diffusion (Kirby-Bauer) Method: Antibiotic-impregnated disks are placed on an agar plate inoculated with the bacteria. The zone of inhibition around each disk is measured to determine susceptibility. Broth Dilution: Dilutions of antibiotics are mixed with a standardized bacterial suspension in broth. The minimum inhibitory concentration (MIC) is determined by observing the lowest concentration that inhibits visible growth. E-test: A strip impregnated with a gradient of an antibiotic is placed on an inoculated agar plate. The MIC is read where the bacterial growth intersects the strip.
