Penicillin Zone Edge

**Semantic type:** Laboratory Procedure

**Definition:** A method that is used to detect beta-lactamase production by assessing the zone edge of penicillin-susceptible bacteria isolates after disk diffusion. A fuzzy zone edge indicates a beta-lactamase negative result and a sharp zone edge indicates a beta-lactamase positive result.

**Synonyms:** - DISK DIFFUSION ZONE EDGE TEST