How much antibiotic can bacteria in a biofilm withstand compared with free-living cells?

1. Free-living cells are called planktonic, and a given antibiotic concentration kills them. 2. The same organisms inside a biofilm can resist up to 1,000 times that concentration. 3. The sticky matrix excludes most antibiotics and disinfectants, which is the physical reason. 4. A dose that large would harm the patient, so simply raising the dose is not a treatment option. 5. Biofilm infections therefore develop slowly, resist host defences and are very hard to eradicate. 6. Options quoting 10 times, half or an equal concentration all understate the gap by a wide margin. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 22 "Prokaryotes: Bacteria and Archaea", section 22.4 Bacterial Diseases in Humans_