Biofilms are communities of micro-organisms that stick to each other and to surfaces. They form in aqueous environments when free-floating micro-organisms attach and adhere to surfaces in response to cues in the environment such as changes in pH and nutrient concentration. The biofilm matures as attached micro-organisms multiply, colonising the surface and recruiting new members which are embedded in self-secreted extracellular polymeric substance (EPS), a sticky slime-like material consisting of DNA, polysaccharides, and proteins, forming a structured 3D matrix.
