Development of functional cellulose materials by utilizing surface selective tailoring concepts

Surface engineering is a widely utilized tool for applications of lignocellusic materials. These methods allow to increase the application potential of cellulose materials towards functional applications e.g. from responsive papers to diagnostic and affinity separation. The functionalization of cellulose materials was monitored by utilizing surface sensitive monitoring tools. The used instruments were Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D) and Surface Plasmon Resonance (SPR). These instruments allow to follow surface behaviour at solid-liquid interface on-line. When cellulosic thin films are deposited on sensors of QCM-D and SPR, the action on cellulose surfaces can be monitored. After on-line monitoring, with QCM-D or SPR, indirect methods as such Atomic Force Microscopy (AFM) and X-Ray Photoelectron Spectroscopy (XPS) can be utilized to verify topological and chemical changes on the cellulose surfaces. In this study we utilized amorphous, crystalline, and fibrous cellulose thin films on researching physical and chemical functionalization of cellulosic material towards functional cellulose applications. The simplest method to functionalize topologically cellulose surfaces is polymer adsorption that was utilized to control proteins adsorption on cellulosic surfaces. This method allows also to install probe molecules, as antibodies, selectively on the cellulose surface enabling diagnostic applications. Moreover, the selection of adsorbed polymers allows to tune the affinity properties of the surface utilized in diagnostic applications. The second approach to install functionalities on cellulose is chemical modification. The used chemical methods were aqueous base e.g. TEMPO mediated oxidation that simultaneously can be utilized in preparation of CNF. The investigated methods were then utilized with cellulose nanofibril (CNF) and bacteria cellulose materials to transfer investigated methods to specific applications. Manufacture of selective CNF films and BC tubes for diagnostic and affinity separation were tested.