Hydrogels based on natural biopolymers, including nanocellulose are becoming interesting in biomedicine. In recent years, researchers have been mainly concerned with the introduction of such hydrogels as a drug delivery systems in the treatment of various diseases. In my master’s thesis I prepared TEMPO-oxidized nanocellulose hydrogels. Hydrogels were crosslinked using different concentrations of calcium chloride to achive more stable structure and higher crosslinking density. By performing viscosity measurements, the effect of crosslinking on hydrogel viscosity was investigated. The obtained results were described by using the Cross model. Based on rheological measurements, the shear modulus were calculate by Maxwell model, through which the crosslinking density and the mesh size of hydrogels were also calculated. The density and porosity of the hydrogels and their relationship to the concentration of added calcium chloride were also determined. The obtained parameters provided a connection between the characterization of hydrogels and the release of molecules from hydrogel networks. In my work I used Fick’s law for one-dimensional system to determine the diffusion coefficient for the release of nicotine into an aqueous medium.
|
