Encapsulated Pseudomonas putida for phenol biodegradation: Use of a structural membrane for construction of a well-organized confined particle

The 3D capsule (right) creates a confined environment that holds the inner microbial suspension while enabling the diffusion of dissolved molecules (e.g., nutrients, gases and organics) through the capsule membrane that has a unique structural architecture (left). The cellulose acetate structural membrane presents highly porous microfiltration channels (estimated pore sizes between 0.2 and 0.8 μm). Furthermore, the entire membrane is constructed as a mesh-like packed structure, with nano-metric channels (∼50-150 nm). The SEM images indicate that the mesh-like structure presents multi-layer rhombus structures which create a mesh-like structure encasing nano-sized pores. The combination of a high density of large-sized pore channels and mesh-like membrane structures enables the achievement of a significant large surface area for dissolved molecule trafficking.643