PREPARATION AND RELEASE PROPERTIES OF A pH-TUNABLE CARBOXYMETHYL CELLULOSE HYDROGEL/METHYLENE BLUE HOST/GUEST MODEL

摘要

PH-sensitive carboxymethyl cellulose (CMC) hydrogel beads were successfully prepared in spherical form by a suspension-cross-linking technique by using epichlorohydrin (ECH) as the crosslinking agent and fluid wax as the suspending solvent. The hydrogel beads are nearly perfect spherical shape with diameter about 4 mm, which exhibits reversible Ph-sensitive behavior. The hydrogel beads have good characteristics of adsorption and release. Their ability to uptaking and releasing cationic guest molecules, such as methylene blue, could be tuned by controlling the degree of carboxylate ionization via Ph. At 25 , °C the maximum loading amount for Methylene Blue (MB) exceeded 1350.6 g/g with 56.27% adsorption ratio.