BETA-LACTAMASE BIOASSAY - A SIMPLIFIED METHOD TO DETERMINE EXTENDED-SPECTRUM BETA-LACTAMASES (ESBL) IN ENTEROBACTERIA

With the simultaneous use of an isoelectric focusing gel (IEF) and a n itrocefin/cefotaxime bioassay, it is possible to identify the Extended -Spectrum beta-lactamases (ESBL) with precision. A mixture of soft aga r and susceptible bacterial cells are layered over the gel following o vernight incubation and areas of cell. growth are detected where the a ntibiotic has been hydrolyzed by specific enzymes. This innovative met hod improves sensitivity and specificity for the identification of ESB Ls in those enterobacteria strains producing more than one beta-lactam ase and are resistant to third generation cephalosporines.