Biofilm refers to an organized bacterial population attached to the surface of living or inanimate objects and wrapped by bacterial extracellular macromolecules. Biofilm bacteria are highly resistant to antibiotics and host immune defense mechanisms. There are various major biological macromolecules such as proteins, polysaccharides, DNA, RNA, peptidoglycan, lipids and phospholipids in biofilms. The formation of multicellular structures in biofilms is a dynamic process that includes stages such as bacterial initiation of adhesion, biofilm development, and maturation diffusion. Learn more: biofilm testing strategy