Antibiotic Discs

Antibiotic discs are used in microbiological studies to observe the effects of various antibiotics on a culture grown on solid medium. A test known as the disc-diffusion test, or the agar diffusion test is performed for this purpose. A pure culture of the organism is plated onto a solid agar plate. The disc containing a specific antibiotic is placed on the agar plate with the microorganism. The antibiotic diffuses into the agar and reaches the microorganisms. In case the antibiotic is effective against the microbe, it eradicates the microbes with the zone in which it has diffused. This creates a halo-like structure around the antibiotic disc. The halo-region is defined as the zone of inhibition and the diameter of this zone is used to find out the effectiveness of the antibiotic in eradicating the microbe and the ability of the antibiotic to diffuse into the agar plate. Discs of several antibiotics are available in the market and can be easily used to classify microorganisms as low, moderately or highly susceptible to the antibiotic.

Biomall offers antibiotic discs of amoxycillin, clavulanic acid, ampicillin and other antibiotics.