Composite Three‐Dimensional Woven Scaffolds with Interpenetrating Network Hydrogels to Create Functional Synthetic Articular Cartilage

Abstract

The development of synthetic biomaterials that possess mechanical properties that mimic those of native tissues remains an important challenge to the field of materials. In particular, articular cartilage is a complex nonlinear, viscoelastic, and anisotropic material that exhibits a very low coefficient of friction, allowing it to withstand millions of cycles of joint loading over decades of wear. Here we show that a three-dimensionally woven fiber scaffold that is infiltrated with an interpenetrating network hydrogel can provide a functional biomaterial that provides the load-bearing and tribological properties of native cartilage. An interpenetrating dual-network “tough-gel” consisting of alginate and polyacrylamide was infused into a porous three-dimensionally woven poly(ε-caprolactone) fiber scaffold, providing a versatile fiber-reinforced composite structure as a potential acellular or cell-based replacement for cartilage repair.

Reinforcement of hydrogels using three-dimensionally printed microfibres

“…The porosity of these woven scaffolds was 70-74%, compared with 93-98% in the present study. The stiffness of the woven composites was reported up to 0.2 Mpa (at equilibrium stress), which was twice as stiff as the scaffold without the gel 22 . Both the woven and the melt-electrospun composites showed axial recovery after compression for 10% and 20%, respectively.…”

“…Hydrogels reinforced with woven scaffolds, composed of either polyglycolic acid 8 or PCL 21,22 , have previously been reported to possess tensile, compressive and shear properties comparable to native cartilage. The porosity of these woven scaffolds was 70-74%, compared with 93-98% in the present study.…”

“…For example, hydrogels have been reinforced with nanofibres [17][18][19] , microfibres 20 and woven 8,21,22 or non-woven 23 scaffolds. The mechanical properties of hydrogels in such composites are less demanding; therefore, they can be processed with a low crosslink density, which is beneficial for cell migration and the formation of neo-tissue 2,3 .…”

Hybrid Hydrogels with Extremely High Stiffness and Toughness

“…19 For example, these hydrogels have been infused into a scaffold of woven fibers to mimic cartilage. 20 Although the alginate-polyacrylamide hydrogels have achieved exceptionally high toughness, their stiffness is modest for three reasons. First, the concentration of alginate in the hydrogel is low; any attempt to significantly raise the concentration of alginate is frustrated by the high viscosity, making it difficult to mix the ingredients to form a homogeneous hydrogel.…”

An experimental fatigue study of a porous scaffold for the regeneration of articular cartilage

“…Other authors try to develop artificial cartilage combining different materials, such as PCL and alginate/polyacrylamide (Liao et al 2013) or chitosan/agarose/gelatin (Bhat, Tripahi, and Kumar 2011) or polylactic acid and agar (Gong et al 2007). Without doubt, the combination of synthetic or natural scaffolding materials with hydrogels for cartilage regeneration is an arising and important field.…”