Preparation And Cytocompatibility Of Chitosan Nanoparticles

Two kinds of chitosan derivatives, linoleic acid modified chitosan (LACH) and deoxycholic acid modified chitosan (DACH), are synthesized and the cytotoxicity of these compounds is tested in this thesis. Nanoparticles are prepared with the 14cp LACH and the cytotoxicity of these nanoparticles to fetal mouse skin fibroblast and the tumor cell lines are analyzed, which provide aids to the practical use of the nanoparticles.LACH,DACH with different molecular weights are synthesized by the formation of amide linkages through the EDC-mediated reaction. The results of FTIR and NMR confirm the successful modification and the degree of substitution (DS) is not influenced by the molecular weight of chitosan. Cytotoxicity of LACH and DACH is investigated via the red blood cell lysis test and the MTT assay. The red blood cell lysis test shows that each sample can be regarded as non-toxic to red blood cells in the solid state, while the cytotoxicity can not be neglected in the solution state. Both kinds of chitosan derivatives exhibit no cytotoxicity to fetal mouse skin fibroblast with the increase of concentration, and are not influenced by molecular weight and time. Compared to the suppressive effect of chitosan to fibroblast, the improvement of cytocompatibility with LACH and DACH may be complex.The self-assembling properties of 14cp LACH are analyzed using the fluorescence probe test, the laser light scattering and the transmission electron microscopy. The results show that LACH molecules tend to assemble when the concentration is higher than 0.1g/l and this trend increases with the rise of concentration. Most of the nanoparticles formed are around 200nm and are of a spherical shape, which indicates that the prepared nanoparticles have good structural integrity. Cytotoxicity of the...