Pulse electromagnetic fields enhance the repair of rabbit articular cartilage defects with magnetic nano-hydrogel

Hydrogel is an important scaffold material in regenerative medicine and cartilage tissue engineering. Hydrogel material combined with pulse electromagnetic fields (PEMFs), PEMFs has the potential to manage the repair of defective articular cartilage. Here, we developed a new type of magnetic hydrogel. The data shows that the magnetic hydrogel had good mechanical properties, and its surface had micropores and unevenness, which was conducive to cell adhesion growth. Infrared spectroscopy analysis showed that the magnetic particles were evenly distributed in the hydrogel, and the addition of constant static magnetic field yielded magnetic water. The hydrogel exhibited good superparamagnetism. The co-culture of the magnetic hydrogel and bone marrow mesenchymal stem cells (BMSCs) showed good biocompatibility. The PEMFs promoted the differentiation of the BMSCs into cartilage, and the index of cartilage differentiation increased obviously. The results of the animal experiments showed that the magnetic hydrogel and BMSCs combined with pulsed electromagnetic field had a strong repair effect. They also showed that the magnetic nano-hydrogel combined with the PEMFs induced chondrogenic differentiation of the BMSCs. The positive experimental results suggested that the combination of magnetic hydrogel and the PEMFs can be used as an effective method for repairing articular cartilage defects in rabbit model.