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• Free-floating bacteria encounter a submerged surface and within minutes can become attached. They begin to produce slimy extracellular polymeric substances (EPS) and to colonize the surface.

• Antibiotics are medicines that fight bacterial infections in people and animals. They work by killing the bacteria.

• A detergent is a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions that fight with bacteria.

Compared to free floating bacteria, bacteria in biofilms often show increased resistance to antibiotics and detergents because:

• The inner bacteria in the biofilm are protected by the extracellular matrix, other bacteria, and its cell wall.

• The process of lateral gene transfer that transfer gene resistance to antibiotic or detergent from one bacterium to the other is easier in the biofilm due to the close proximity of bacteria to each other.

• The enzyme that is secreted by one bacterium can destroy and protect the neighboring bacteria from antibiotic and detergent.