Abstract

This study presents a modification of the antibiotic susceptibility testing (AST), which is a rapid means of determining the response of planktonic bacteria to different antimicrobial agents, for application to biofilms. Colony biofilm was first developed on a cellulose filter/membrane disc, over which an antibiotic disc was imposed. Zone of inhibition was measured after incubation on nutrient agar. Biofilms were not as susceptible to the test antibiotics as compared to the planktonic cultures. The results point to the possibility of this method as a rapid means for antibiotics for treating biofilm infections. Limitations and potential application for biofilm AST are discussed.

Key words:  Biofilm, antibiotic susceptibility testing