ANTIBIOTIC SENSITIVITY TEST Aim To determine the sensitivity (sensitive or resistant) of Antibiotics against bacterial pathogens. Principle An antibiotic sensitivity (or susceptibility) test is done to help choose the antibiotic that will be most effective against the specific types of bacteria infecting an individual person. One method that is used to determine antibiotic susceptibility is the sensitivity disk method of Kirby - Bauer (named after W. Kirby and A. W. Bauer in 1966). In this method, antibiotics are impregnated onto paper disks and then placed on a seeded Mueller-Hinton agar plate using a mechanical dispenser or sterile forceps. The plate is then incubated for 16 to 18 hours, and the diameter of the zone of inhibition around the disk is measured. The inhibition zone diameter that is produced will indicate the susceptibility ...