Fabrication and evaluation of homogeneous alginate/polyacrylamide–chitosan–gelatin composite hydrogel scaffolds based on the interpenetrating networks for tissue engineering

Abstract

Interpenetrating polymer network (IPN) is generally considered to be one of the most effective methods for imparting high-strength mechanical properties to hydrogel materials. To broaden the application of alginate hydrogel in skeletal muscle or muscle tissue engineering, the interpenetrating network technology and layer-by-layer (LBL) electrostatic assembly were proposed to fabricate the homogeneous alginate/polyacrylamide-chitosangelatin (Alg/PAAM-CS-GT) composite hydrogel scaffolds, using the hydroxyapatite/D-glucono-δ-lactone (HAP/GDL) complex as the gelling system. The effects of different components of alginate/polyacrylamide (Alg/PAAM) on the morphology, mechanical properties, swelling, degradability, and cytocompatibility of the hydrogel scaffolds were comparatively characterized. Experimental results showed that the as-prepared Alg/PAAM-CS-GT composite hydrogel scaffolds exhibited sharp edges and regular 3D structures. Their pore structure could be regulated by changing the content of PAAM in Alg/PAAM-CS-GT composite hydrogel scaffolds. And the filling of PAAM reduced the pores and thickened the pore walls, which obviously enhanced the mechanical properties of Alg/PAAM-CS-GT composite hydrogel scaffolds. FT-IR and thermogravimetric analysis showed that O‧‧‧N hydrogen bonding between COOH of SA and NH 2 of PAAM could be helpful to improve the thermal stability of the composite hydrogel scaffolds. The swelling and biodegradation measurements indicated that the swelling and degradation of Alg/PAAM-CS-GT composite hydrogel scaffolds could be effectively regulated by changing the component content of the composite hydrogel. In addition, the in vitro cytocompatibility analysis showed that the Alg/PAAM-CS-GT composite hydrogel scaffolds could support the growth of MC3T3-E1 cells and promote cell proliferation and differentiation. According to the in vitro cytocompatibility test results, the optimum PAAM content for the Alg/PAAM-CS-GT composite hydrogel scaffolds was 60%. Because of good morphology, well-developed pores, excellent mechanical properties, and high

Comparative Study of Physicochemical Properties of Alginate Composite Hydrogels Prepared by the Physical Blending and Electrostatic Assembly Methods

“…Of note, Alg-GT, Alg-CS, Alg-CS-GT and ALG/GT-CS displayed similar pore structures, as shown in Figure 3 b,d,f,h, implying that the electrostatic assembly of biomacromolecules did not destroy the porous structure of alginate composite hydrogels. The homogeneous hydrogels prepared with HAP/GDL as the cross-linking agent formed ice crystals uniformly in the hydrogels after freezing treatment, and the ice crystals were sublimated under negative pressure, leaving open porous structures in the hydrogels [ 37 , 38 ]. The porosities of the composite hydrogels measured by mercury porosimeter are shown in Table 3 .…”

“…As shown in Figure S2 , the cells almost filled the whole tissue culture plate within 2 days. However, the OD value of alginate composite hydrogels was higher than that of the control because of their good 3D morphology and porous structure, which could provide space for the three-dimensional proliferation of cells [ 37 ]. The low proliferative activity of ALG Gel may be related to its lack of cell-specific binding sites [ 30 ].…”

Design, characterization and evaluation of homogeneous oxidized sodium alginate/polyacrylamide–gelatin composite hydrogels constructed via interpenetrating network technology

“…After incubating for 2 days, the adhesion and spreading of the cells on the composite hydrogels were examined by SEM observation after they were fixed by chemically crosslinking with glutaraldehyde and freeze‐dried. The proliferation activity of the cells on the composite hydrogels was evaluated by CCK‐8 assay according to our previous work 33 . After 2 and 7 days of incubation, 50 μL of CCK‐8 reagent was added to 500 μL of medium in each well in the 24‐well culture plates, and then they were placed in the incubator at 37 °C for 4 h. Finally, 100 μL of solution from each well was transferred to a 96‐well plate.…”

In Vitro and In Vivo Biocompatible and Controlled Resveratrol Release Performances of HEMA/Alginate and HEMA/Gelatin IPN Hydrogel Scaffolds

“…The development of interpenetrating polymer network hydrogels as scaffolding biomaterials can provide cells with an adhesive extracellular matrix-like 3D microenvironment possessing the mechanical integrity to withstand physiological forces. These hydrogels can be synthesized from biologically derived or synthetic polymers, the former polymer offering preservation of adhesion, degradability, and microstructure, and the latter offering tunability and superior mechanical properties [ 26 ].…”