Cellulose-based biomaterials: a plot twist

In recent years, chemical protocols in various academic, clinical, and industrial studies around the world have begun to slowly shift their norms toward finding safer ways for the production of novel materials and technologies. New directions rely on basing design concepts inspired from nature-sourced polymers, which are thought to hold great promise as virtually inexhaustible source materials. The perfection of chemically modifying these polymers is therefore relevant now more than ever, with far-reaching and diverse applicative prospects. As a model biopolymer, cellulose has a rich history of industrial uses, and is still incorporated in over 1200 patents annually. In an ocean of man-made synthetic polymers, one discovery stood out, as the Cegelski group from Stanford University unearthed the identity of the first-ever recorded naturally modified cellulose. Secreted by E. coli bacteria to form an extracellular matrix that shields them from environmental factors in a biofilm setting, this polymer was named pEtN cellulose, after its distinctive phosphoethanolamine side chain. This discovery illuminated the fact that bacteria can make a modified cellulose with interesting functional consequences, and it inspired us to think of the pEtN modification specifically, which is not listed among the plethora of artificial cellulose derivatives currently in the literature. The work presented describes the exploratory path in discovering the pEtN side chain’s potential in the design and application of novel biomaterials. This includes synthesizing pEtN cellulose in a number of ways, and also working on incorporating the pEtN side chain onto other polymeric backbones. The specificity and nature of these newly designed polymers depend on the goal to which the intended biomaterials are to be used, and so possible future applications are very diverse. These range from food related applications, through pharmaceuticals and medical devices, and all the way to templates in genetically designed plants as alternative feed sources in bioethanol fuel production. Given the rich history of cellulosic materials, it is fair to assume this naturally formed side chain will also be incorporated into many new and exciting research avenues.