Citric acid cross-linking of highly porous carboxymethyl cellulose/poly(ethylene oxide) composite hydrogel films for controlled release applications

Abstract

Herein, highly porous hydrogel made up from citric acid cross-linking of carboxymethyl cellulose (CMC) composite with poly(ethylene oxide) (PEO). The swelling behavior of CMC/PEO hydrogel was evaluated based on four parameters; ratio of CMC to PEO, percentage of citric acid, temperature and duration of curing. The optimum degree of swelling was found to be at 3:1 ratio of CMC/PEO, 10% of citric acid, 70°C of curing temperature and 450 minutes of curing time. Degree of swelling and thermal stability of the hydrogel film improved when CMC was composited with PEO compared to CMC alone. Gel fraction of CMC/PEO hydrogel film was 44.17% with high loading percentage of 82.69 ± 0.58% of methylene blue (MB). The MB released from CMC/PEO hydrogel was pH dependent, where MB was released with low concentration in acidic environment compared to basic environment. The results show CMC/PEO hydrogel have high potential to be used in controlled drug release for biomedical applications.