Antibiotic susceptibility testing
Antimicrobial resistance (AMR) is the ability of bacteria to stop an antimicrobial (antibiotics) from working against it. As a result, standard treatments become ineffective, infections persist and may spread to others.
Antibiotic susceptibility testing can be used in the context of identification, screening, or species description.
We offer disc-diffusion antibiotic susceptibility testing performed according to the CLSI M100S 26th Edition (2016) recommendations for any bacterial sample up to biosafety level 2 (BSL-2).
Disc-diffusion method uses antibiotic-containing wafers or disks to test whether particular bacteria are susceptible to specific antibiotics. First, a pure culture of bacteria should be isolated from the sample. Then, a known quantity of bacteria are grown overnight on agar (solid growth media) plates in the presence of a thin wafer that contains a known amount of a relevant antibiotic. If the bacteria are susceptible to the particular antibiotic from a wafer, an area of clear media where bacteria are not able to grow surrounds the wafer, which is known as the zone of inhibition. A larger zone of inhibition around an antibiotic-containing disk indicates that the bacteria are more sensitive to the antibiotic in the disk.