Preparation and characterization of cellulose composite hydrogels from tea residue and carbohydrate additives

• Cellulose was extracted from tea residue and prepared into composite hydrogels with four additives.
• Addition of chitosan and guar gum improved at TPA parameters and thermostability.
• Addition of κ-carrageenan and soluble starch improved hydrogels at equilibrium swelling ratio and NaSA loading ratios.
• Tea cellulose composite hydrogels showed non-cytotoxicity and cell compatibility.

Composite hydrogels were prepared from tea cellulose in ionic liquid of 1-allyl-3-methylimidazolium chloride and effect of κ-carrageenan, chitosan, guar gum and soluble starch on characteristics of the prepared hydrogels were investigated. The prepared hydrogels were characterized via Fourier transform infrared, thermogravimetry analysis, differential scanning calorimetry. Sodium salicylate was used as the model drug to compare the swelling, drug loading and releasing kinetics of the prepared hydrogels. Thiazolyl blue tetrazolium bromide assay and relative growth rates were adopted to evaluate cell cytotoxicity and biocompatibility of the prepared hydrogels. Chitosan and guar gum could improve thermostability and mechanical characteristics of the composite hydrogels, while κ-carrageenan or soluble starch could improve equilibrium swelling ratio, sodium salicylate loading and releasing. Guar gum and chitosan could increase permeation resistance and were beneficial for release control of the hydrogels. Addition of chitosan, κ-carrageenan, guar gum and soluble starch were proven cell compatibility and non-cytotoxicity.