The aim of this paper was to investigate the effects of cross-linked reaction on physicochemical properties of chitosan film by using genipin as cross-linker agent. Series of chitosan film samples with different amount concentration of genipin loaded (0-3 wt %) were prepared and characterized. The physicochemical properties of films were evaluated by Fourier Transform Infra-red (FTIR), UV-vis spectroscopy, Oxygen Transmission Rate (OTR), Scanning Electron Microscopy (SEM), water vapour and tensile test. The cross-linking reaction had affected on colour changing of chitosan film samples from light yellow to dark blue in line with the increasing of genipin concentration. Thus, UV-vis spectroscopy on the cross-linked samples showed the absorbance value at 600 nm wavelength due to genipin content. FTIR observation on cross-linked film samples showed no characteristic of –OCH3 peak from genipin at 1444 cm-1 which resulted by new covalent bonding occurred between chitosan and genipin. Cross-linking also had increased the oxygen barrier and reduced the water vapor rate through the film. Chitosan film sample with addition of 1 wt% genipin achieved the highest tensile stress average at 49.46 MPa compared to other samples while percent of elongation at break reduced with the increasing of genipin concentration loaded

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The aim of this study was to investigate the effects of covalent and ionic cross-linked reactions which were respectively done by using genipin and tripolyphosphate (tpp), on the structure and mechanical properties of chitosan film. Both cross-linked and uncross-linked films were prepared by solution casting method and characterized. FTIR spectra showed no characteristic of –OCH3 peak from genipin at 1444 cm-1 which resulted by a new covalent bonding in chitosan film. Reduction in absorption intensity at 1560 cm-1 wave number in chitosan cross-linked tpp films were due to the presence of ionic interaction between the positive charged of amino group in chitosan and negatively charged of phosphate group by tpp. The pattern area from the XRD results showed that the covalent cross-linked had significantly changed on the chitosan`s degree of crystallinity. The water contact angle on the surface of covalent/ionic cross-linked chitosan film reached the highest θ at 82.72° which indicated more hydrophobic properties was formed. Covalent/ionic cross-linked chitosan also showed the higher mechanical strength with average tensile stress value at 71.25 MPa. All finding results demonstrated that cross-linked modification on the chitosan film had successfully reduced the film’s hydrophilicity and increased the mechanical properties of the film.

This paper work proposes the idea of super hydrophilic chitosan development in porous sponge form as the bottom part of bi-layer skin regenerating template. In this experiment, 5 different ratios of chitosan: methylcellulose have been prepared by varying the amount of methylcellulose from 10 %, 20 %, 30 %, 40 %, to 50 %. The formation of chitosan-cellulose scaffold will be carried out through combination of moist providing methylcellulose and wound-healing chitosan. The advantages of using methylcellulose on hydrophilicity of the template was characterized through FTIR analysis and wettability study, while their morphology was characterized using Variable Pressure Scanning Electron Microscope (VPSEM). The polymeric structure of polyanion methylcellulose which contains hydroxyl (-OH) functional group, analyzed using FTIR analysis was expected to attract H2O molecule from the moisture, hence providing the hydrophilic properties of the polymer. Water uptake study shows that as the percentage of methylcellulose used in the template increased, the water uptake of the template also increased. However, increasing the amount of methylcellulose did not give a significant different to the porosity of the template.