MCM-41/chondroitin sulfate hybrid hydrogels with remarkable mechanical properties and superabsorption of methylene blue.

This paper describes the synthesis of hybrid hydrogels based on chondroitin sulfate (CS) and mesoporous silica (MCM-41). The combination of the CS network and surface-modified MCM-41 yields resilient hybrids with a high water absorption power and excellent capacity for the removal of methylene blue (MB). In this system, two types of solute transport mechanisms exist: absorption and adsorption. The effect of MCM-41 on the physical-chemical properties of the hydrogels was assessed over a wide pH scale, and the absorption kinetics and isotherms of MB were studied by theoretical models. The mechanical properties of the hydrogels, such as the modulus of elasticity, yield strength, modulus of resilience, and fracture toughness, were significantly improved. This hydrogel exhibited high performance for water absorption (4000 % beyond its initial weight) and removal of MB (3982 ± 123.6 mg g), while the pure hydrogel removed 2912 ± 163.8 mg g.