Double Network Hydrogels that Mimic the Modulus, Strength, and Lubricity of Cartilage.

The development of a hydrogel-based synthetic cartilage has the potential to overcome many limitations of current chondral defect treatments. Many attempts have been made to replicate the unique characteristics of cartilage in hydrogels, but none have simultaneously achieved high modulus, strength, and toughness while maintaining the necessary hydration required for lubricity. Herein, double network (DN) hydrogels, composed of a poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) first network and a poly( N-isopropylacrylamide- co-acrylamide) [P(NIPAAm- co-AAm)] second network, are evaluated as a potential off-the-shelf material for cartilage replacement.

Thermoresponsive Double Network Hydrogels with Exceptional Compressive Mechanical Properties.

The utility of thermoresponsive hydrogels, such as those based on poly(N-isopropylacrylamide) (PNIPAAm), is severely limited by their deficient mechanical properties. In particular, the simultaneous achievement of high strength and stiffness remains unreported. In this work, a thermoresponsive hydrogel is prepared having the unique combination of ultrahigh compressive strength (≈23 MPa) and excellent compressive modulus (≈1.