Bacterial Nanocellulose Biomaterials with Controlled Architecture for Tissue Engineering Scaffolds and Customizable Implants

The bacterium Gluconacetobacter xylinus (previously known as Acetobacter xylinum) has been shown to produce cellulose fibrils of 10–30 nm in diameter. Through careful control of their motion, it is possible to direct them to produce well-defined three-dimensional (3D) scaffolds for tissue reconstruction. This chapter reviews the state of the art in fabrication of tissue engineered structures and biomedical implants using bacterial nanocellulose (BNC). Of particular focus is the use of electric fields to produce highly oriented cellulose networks and also the development 198of a microvascular network within BNC structures. The movement of G. xylinus at the nanoscale can be controlled by electric fields to create custom cellulose networks for engineered tissues and biomedical implants. This is the first attempt to control a bottom-up biofabrication process in three dimensions. The manipulation of electrokinetic forces acting upon a bacterial cell can produce complex cellulose patterns on the nanoscale not achievable in static culture. The ability to control the direction of fiber orientation could be readily expanded to weave structures of multiple fiber layers by changing the orientation of the applied electric field for each layer. Using this method, these structures could be tailored to have desired mechanical properties for a variety of applications, including tissue engineering, microelectromechanical systems (MEMS), textiles, and electronics.