ABSTRACT
In this paper, carbon nanotubes [CNTs] were added into chitosan [CS] hydrogels in the form of chitosan modified CNTs [CS-CNTs] composites to prepare carbon nanotubes hydrogels [CNTs-GEL]. The products, named CS-MWCNTs, were characterized by scanning electron microscope [SEM] and Fourier transform infrared [FTIR] spectroscopy. Swelling properties and effect of pH on controlled release performance of the two kinds of hydrogels, CNTs-GEL and pure chitosan hydrogels without CNTs [GEL], were investigated respectively. The results showed that CNTs-GEL possess better controlled release performance than GEL. The releasing equilibrium time of CNTs-GEL was longer than that of GEL in both pH = w7.4 and pH=1.2 conditions, although the release ratios of the model drug are similar in the same pH buffer solutions. It is found that release kinetics is better fitted Ritger-Peppas empirical model indicating a fick-diffusion process in pH = 1.2, while in pH = 7.4 it was non-fick diffusion involving surface diffusion and corrosion diffusion processes