Biofilms are groups of microbial cells that aggregate on surfaces and Interfaces. The cells in a biofilm are encased in an Extracellular Matrix (ECM) that serves as a shield for the cells from antibiotic activity. The ECM is a network of biopolymers, mainly polysaccharides and proteins, which composes more than 90% of the dry weight of biofilms. Our general aim is to study the structure of the biopolymers within the biofilm, their orientation and spatial distribution along the biofilm, and to correlate them with the structure of the purified biopolymers. In this proposal we extend our study from 2D biofilms into studying structural and metal ions gradients in biofilms cross sections