Scaffolding via click chemistry: new strategy for tissue engineering

Introduction Cellulose-derivatives-based hydrogel is a biodegradable and biocompatible which can be used as a scaffold for tissue engineering. So far, different chemical crosslinkers have been used for hydrogel synthesis through chain crosslinking. Click chemistry as a novel method for hydrogel synthesis has attracted a lot of attentionrecently. In this paper, we focus on the cellulose chain crosslinking using click chemistry. Objectives To synthesize hydroxyethyl cellulose (HEC) hydrogel using click chemistry, surface modification of HEC chain with azide and alkyne molecules is necessary to link the chains by strain-promoted alkyne-azide cycloaddition (SPAAC) reaction. Methods In order to modify HEC chain with amino terminated of azide and alkyne molecules, conversion of OH to COOH on HEC chain was essential. For this reason, HEC chain modified with cirtic acid firstly. Azide and alkyne molecules were linked to HEC chain by forming the amide bond through the reaction of carboxylic acid and amine groups. Finally, crosslinking of modified HEC chain was done by reaction of azide with alkyne and triazol ring forming. Results HEC modification with citric acid, azide molecules, alkyne molecules and triazol was investigated by Fourier-transform infrared spectroscopy (FTIR) analysis. Peaks at around of 1610 cm-1, 2100 cm-1, 2205 cm-1 and 1450 cm-1 were related to amide bond, azide, alkyne molecules and triazol ring, respectively. Conclusion Crosslinking of cellulose with click chemistry reaction is a novel method. In this work, we could crosslink the HEC by SPAAC reaction and with no catalyst successfully

Keywords:

Click chemistry , Hydroxyethyl cellulose , Crosslinking