Biocompatible hydrogel based on aldehyde-functionalized cellulose and chitosan for potential control drug release

The present study aimed to prepare cellulose-based biodegradable hydrogel that revealing a potential control of drug release. To achieve this purpose, activation of cellulose was achieved firstly by pretreatment stage using ZnCl2. Then, selective oxidation of activated cellulose was performed by using sodium periodate to achieve cleavage of the bond between C2 - C3 in the glucose unit generating two active aldehyde groups. The modified cellulose (Dialdehyde cellulose, DAC) was reacted with chitosan, in different molar ratios, via condensation between aldehyde and primary amine groups situated onto cellulose and chitosan, respectively. The activated cellulose, DAC, and produced hydrogels were characterized via FTIR, XRD, and SEM to detect the emerging functional groups as well as the variation of crystallinity and surface morphology features of activated cellulose, DAC, and hydrogels. The swelling capacities of hydrogels showed the optimum value at pH = 7.0. The prepared hydrogels cytotoxicity was investigated toward normal skin fibroblast by MTT assay. It was found that the cells treated with chitosan/DAC hydrogels with ratio 1:1, 1:2, and 1:3 affected by 1.3, 1.8, and 0%, respectively. Streptomycin was incorporated in the prepared hydrogels and its release was evaluated. The DAC ratio was played a key role in controlling the release process. Moreover, further studies were carried out on chitosan (PDB: 2RVA) to evaluate its potential interaction with DAC and streptomycin with binding energies -4.4 and - 4.3 kcal/mol with short bond lengths 1.3 and 1.944 angstrom, respectively.