High-strength functionalized pectin/fibroin hydrogel with tunable properties: A structure-property relationship study

Hydrogels possessing high mechanical strength and well-controlled properties are of utmost interest in bone tissue engineering. In the current study, a strong self-crosslinked hydrogel with variable properties has been developed from a combinatory composition of functionalized pectin and silk fibroin. Pectin chains underwent partial oxidation to be decorated with aldehyde functionalities. Later on, functionalized polysaccharide and protein were blended with different ratios, and corresponding variations in crystalline structure as well as in morphological, mechanical, and rheological properties have been monitored. Some theories have been used to better perceive the relation between blending ratio and hydrogel properties. Avrami equation based on time sweep rheological analysis elucidated that in sample with equivalent ratio of oxidized pectin and fibroin, the crystallization was highly delayed due to dominance of Schiff's base reaction. The Herschel-Bulkley model based on flow curve rheology test corroborated that aforesaid composition revealed the most noticeable shear thinning behavior and accordingly the strongest crosslinked network. Finally, rubber elastic theory based on dynamic mechanical analysis implied that said formulation possessed the highest crosslinking density due to higher availability of aldehyde to amine functionalities. Moreover, cell culture studies proved that P50 F50 sample prevailed over other compositions with respect to cell viability and function. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48859.