A Biphasic Hydrogel with Self-Healing Properties and a Continuous Layer Structure for Potential Application in Osteochondral Defect Repair

Abstract

The treatment of osteochondral defects remains challenging due to the limited healing capacity of cartilage and the poor results of traditional methods. Inspired by the structure of natural articular cartilage, we have fabricated a biphasic osteochondral hydrogel scaffold using a Schiff base reaction and a free radical polymerization reaction. Carboxymethyl chitosan (CMCS), oxidized sodium alginate (OSA), and polyacrylamide (PAM) formed a hydrogel (COP) as the cartilage layer, while hydroxyapatite (HAp) was incorporated into the COP hydrogel to obtain a hydrogel (COPH) as an subchondral bone layer. At the same time, hydroxyapatite (HAp) was incorporated into the COP hydrogel to obtain a hydrogel (COPH) as an osteochondral sublayer, combining the two to obtain an integrated scaffold for osteochondral tissue engineering. Interlayer interpenetration through the continuity of the hydrogel substrate and good self-healing properties due to the dynamic imine bonding of the hydrogel resulted in enhanced interlayer bond strength. In addition, in vitro experiments have shown that the hydrogel exhibits good biocompatibility. It shows great potential for osteochondral tissue engineering applications.

Self‐healing mineralized hydrogel scaffolds for stretch‐triggered dye release

“…The healing efficiency of the SHMH can be calculated as the tensile strength of the self-healed SHMH versus the original SHMH. 7,11 Healing efficiency % ð Þ¼…”

“…Self‐healing is a property commonly found in living organisms that enables partial or total restoration of cells and tissues after physical/chemical/mechanical damages 6 . The self‐healing ability is the ability of the hydrogel to achieve external force‐free healing, restore mechanical properties, and finally extend the life of the hydrogel 7 . With the advent of self‐healing properties, it is possible to achieve complete recovery of the structure of hydrogel, 8 which will prevent the leakage of loaded agents even if the hydrogels are damaged during administration.…”

“…With the advent of self‐healing properties, it is possible to achieve complete recovery of the structure of hydrogel, 8 which will prevent the leakage of loaded agents even if the hydrogels are damaged during administration. Self‐healing hydrogels have received much attention because of their ability to maintain the structural integrity of the hydrogel network 7 . Hydrogels with self‐healing properties have potential applications in areas, such as cancer therapy, drug delivery, tissue engineering, wound dressings, human sensors, robotics, 3D printing, and contact lenses.…”

“…6 The self-healing ability is the ability of the hydrogel to achieve external force-free healing, restore mechanical properties, and finally extend the life of the hydrogel. 7 With the advent of self-healing properties, it is possible to achieve complete recovery of the structure of hydrogel, 8 which will prevent the leakage of loaded agents even if the hydrogels are damaged during administration. Self-healing hydrogels have received much attention because of their ability to maintain the structural integrity of the hydrogel network.…”

“…Self-healing hydrogels have received much attention because of their ability to maintain the structural integrity of the hydrogel network. 7 Hydrogels with self-healing properties have potential applications in areas, such as cancer therapy, drug delivery, tissue engineering, wound dressings, human sensors, robotics, 3D printing, and contact lenses.…”