Characterization and behavior of composite hydrogel prepared from bamboo shoot cellulose and β-cyclodextrin

• Carboxymethyl cellulose was prepared from bamboo shoots via chemical modification.
• Modified bamboo shoot cellulose and β-cyclodextrin were cross linked to hydrogel.
• The hydrogel showed perfect swelling ratio at low temperature and high pH value.
• The prepared hydrogel was sensitive to changes of temperature, pH value and salt.
• Drug release ratio of hydrgel differed in simulated intestinal and gastric liquid.

Carboxymethyl cellulose was derived from bamboo shoot cellulose via chemical modification and was prepared into composite hydrogels by cross-linkage with β-cyclodextrin using epichlorohydrin as crossing agent. The structure of the prepared hydrogel was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. The results showed that the prepared composite hydrogel was sensitive to surrounding changes in pH value, temperature and ionic strength. Under the surroundings of low temperatures and high pH values, the prepared hydrogel had significant high swelling ratios (23338 ± 988% at 15 °C and 6937 ± 112% at pH 8.0, respectively). In the solution of 0.1 mol/L NaCl, the hydrogel showed the maximum water retention rate (48.73%). Sodium salicylate was used as the model drug to study the behaviors of hydrogel adsorption and release in simulated intestinal (at pH 7.4) and gastric liquid (at pH 1.8) surroundings. The prepared composite hydrogel exhibited higher drug release ratio in simulated intestinal liquid (63.09% after 380 min) than in gastric liquid (22.09% after 400 min). These pH responses of the prepared composite hydrogel showed its potential applications, especially as the drug carrier to attain control release of drugs under different surrounding conditions or organs in human body.