Cartilage-bone inspired the construction of soft-hard composite material with excellent interfacial binding performance and low friction for artificial joints

Abstract

Inspired by the cartilage-bone structure in natural joints, soft-hard integrated materials have received extensive attention, which are the most promising candidates for artificial joints due to their combination of excellent load-bearing properties and lubricating properties. The latest progress showed that the combination of hydrogel and titanium alloy can realize a bionic natural joint lubrication system on the surface of titanium alloy. However, obtaining a tough interface between the hydrogel (soft and wet) and the titanium substrate (hard and dry) is still a great challenge. Here, we designed a “soft (hydrogel)-hard (Ti6Al4V)” integrated material with outstanding combination, which simulates the structure and function of cartilage-bone in the natural joint. The load-bearing properties, binding performance, and tribological behaviors for different forms of the soft-hard integrated materials were investigated. The results showed that the hydrogel layer and Ti6Al4V substrate possess ultra-high interfacial toughness (3,900 J/m2). In addition, the combination of the hydrogel layer and Ti6Al4V substrate provided a good lubrication system to endow the “soft (hydrogel)-hard (Ti6Al4V)” integrated material with high load-bearing and excellent tribological properties. Therefore, this study provided an effective strategy for prolonging the service life of Ti6Al4V in the biomedical field.

Construction and tribological properties of poly acrylic acid‐poly(3‐(methacryloylamino)propyl) dimethyl(3‐sulfopropyl)ammonium hydroxide hydrogel coatings embedded with SiO2 nanoparticles on Ti6Al4V substrate

“…Kai Chen et al designed PVA/HA/PAA/PDA soft hydrogel on hard Ti6Al4V substrate via PDA adhesive layer. 42 The Ti6Al4V-hydrogel exhibited excellent lubricating performance and a low friction coefficient. Xiong and coauthors constructed PVA hydrogel coating on laser texturing Ti6Al4V alloy substrate, 43 which exhibited a hydrophilic surface with a static water contact of 32 and a low friction coefficient.…”

“…Recently, researchers have developed hydrogel coatings on rigid substrates to mimic the structure and functionality of cartilage‐bone in the natural joint, aming to improve the tribological properties. Kai Chen et al designed PVA/HA/PAA/PDA soft hydrogel on hard Ti6Al4V substrate via PDA adhesive layer 42 . The Ti6Al4V‐hydrogel exhibited excellent lubricating performance and a low friction coefficient.…”

Tough Bonding of PVA Hydrogel-on-Textured Titanium Alloy with Varying Texture Densities in Swollen State

“…Articular cartilage lesions are a common symptom of osteoarthritis (OA), a prevalent disease that causes disability, even among young patients. , Unfortunately, the intrinsic inability of articular cartilage to self-heal due to its avascular and aneural nature has led to the extensive use of artificial cartilage materials to replicate its biofunction. − To date, no candidate materials have been able to fully replicate the natural cartilage’s function. Hydrogels are considered promising substitutes for damaged cartilage due to their similar porous biphasic structure with high water content. , However, their lack of adequate load-bearing capacities limits their broader application .…”

Bioinspired Hard–Soft Composite Scaffold with Excellent Lubrication and Osteogenic Properties for the Treatment of Osteochondral Defect

“…In contrast, heterogeneous bilayer scaffolds can integrate materials with significantly different functional, structural, and mechanical properties, therefore biomimicking the natural organization of articular cartilage and subchondral bone. [6,7] In a healthy state, articular cartilage is a typical superlubrication system, which contains ≈80% interstitial water and 20% extracellular matrix permeated by a large number of charged macromolecules, proteins, chondrocytes, and other components. [8] The polyelectrolyte macromolecules are complexed with phosphatidylcholine lipids to expose phosphorylcholine groups on the cartilage surface to form a hydrated lubrication layer, allowing articular cartilage to exhibit an extremely low friction coefficient (COF, 0.001-0.01) over a wide range of shear rates and at the pressures in excess of 100 atm.…”

“…In contrast, heterogeneous bilayer scaffolds can integrate materials with significantly different functional, structural, and mechanical properties, therefore biomimicking the natural organization of articular cartilage and subchondral bone. [ 6,7 ]…”