Nanocellulose is a promising material with many potential applications. This thesis deals with the optimization of its production and its further use by converting it into incredibly useful nanocellulose hydrogels via a novel, not yet tested, crosslinking mechanism. First, the use of an alternative and environmentally friendlier method for increasing the total surface charge on TEMPO oxidized cellulose was investigated and its impact on the fibrillation process evaluated. It was shown that using alternative reagents for post oxidation can increase the total surface charge and aid fibrillation. After that the TEMPO oxidized cellulose nanofibrils were used in combination with reactive iodinated alkanes to produce crosslinked TEMPO oxidized cellulose nanofibril gels. The obtained crosslinked gels were analyzed for their chemical structure, rheological and mechanical properties to determine how different types of crosslinkers effect the properties of these materials and if control of these properties is viable by choosing the type and amount of crosslinker. Crosslinker type and amount had a strong influence both on the rheological and mechanical properties of the crosslinked gels. Finally, the drug release profiles of gels were analyzed as well as their cytotoxicity. The results showed that the crosslinked TEMPO oxidized nanocellulose gels had 1st order drug release characteristics as well as being non-cytotoxic.
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