Preparation, Characterization, and Biological Testing of Novel Magnetic Nanocomposite Hydrogels

Abstract

To provide a novel approach for the clinical treatment of cartilage tissue defects, we prepared a new type of magnetic nanocomposite hydrogel with an optimal raw material ratio using Fe3O4, polyvinyl alcohol (PVA), and type-II collagen (COLII). Briefly, five groups of PVA and collagen hydrogel matrices with different mass ratios were prepared by a combination of repeated thawing cycles and foam-frozen ice crystal separation methods. Microscopic characterization was conducted using electron microscopy, and the biomechanical properties of each group of hydrogels were then tested. The highest performing component hydrogel matrix was selected after which Fe3O4 with different mass ratios was introduced to construct a new Fe3O4/PVA/COLII hydrogel. The prepared composite hydrogels were also microscopically characterized using electron microscopy along with scanning, measurements for porosity and moisture content, and biomechanical, infrared spectrum and degradation performance testing. CCK-8 detection and staining to determine the amount of living and dead cells were also performed. Collectively, these results showed that PVA/COLII,95:5 was the optimal hydrogel matrix. Using this hydrogel matrix, five groups of composite hydrogels with different Fe3O4 mass ratios were then prepared. There was no significant difference in the microscopic characteristics between these different hydrogels. Fe3O4/PVA/COLII,5:95:5 had better physical properties as well as swelling performance and cell compatibility. The PVA/COLII,95:5 hydrogel matrix was determined to be the best, while the new magnetic nanocomposite hydrogel Fe3O4/PVA/COLII,5:95:5 had good, comprehensive properties.

Collagen‐Based Hydrogels for Cartilage Regeneration

“…Thus, PVA combined with collagen can be used in different ratios to synthesize new composite hydrogels with different functions for cartilage regeneration. 123 Xie et al utilized 3D printing to synthesize a novel hybrid PVA collagen hydrogel that mimics the properties of natural cartilage and provides mechanical support in which the collagen scaffold allows the hydrogel to integrate with the surrounding natural cartilage. 124 Polycaprolactone/Collagen Composite Hydrogels Polycaprolactone (PCL) is a synthetic polymer, which has certain rigidity, good compatibility with polymer materials, can also be used as a modifier for other polymers, and is widely used in biomedical field.…”

“…As well, Huang et al produced a novel magnetic nanohydrogel using Fe 3 O 4 , PVA, and COL II in an optimal ratio of 5:95:5. Thus, PVA combined with collagen can be used in different ratios to synthesize new composite hydrogels with different functions for cartilage regeneration 123 . Xie et al utilized 3D printing to synthesize a novel hybrid PVA collagen hydrogel that mimics the properties of natural cartilage and provides mechanical support in which the collagen scaffold allows the hydrogel to integrate with the surrounding natural cartilage 124 …”

Modification of mesenchymal stem cells for cartilage-targeted therapy

“…We have developed magnetic nanocomposite-combined MSCs for the treatment of cartilage defects. Stem cell differentiation was promoted by exposure to a pulsed electromagnetic field, which has broad applications in cartilage tissue engineering [90][91][92]. Kobayashi et al labeled BMSCs with Feridex and injected them into rabbit and pig models of osteochondral defect, showing enhanced engraftment into the chondral defect under external magnetic force [93].…”

Iron Oxide Nanoparticles in Regenerative Medicine and Tissue Engineering

“…Again, the hydrogel could be visualized by MRI for at least 19 days after transplantation [ 297 ]. Recently, Huang et al published a study involving the preparation of magnetic nanocomposite hydrogels from Fe 3 O 4 , polyvinyl alcohol (PVA) and type II collagen, which exhibited good physical properties as well as good swelling behavior and cell compatibility [ 298 ]. In another work, Yang et al fabricated scaffolds of cross-linked collagen/cellulose nanocrystals in which ultra-small IONPs functionalized with the chondroinductive small molecule kartogenin were incorporated [ 299 ].…”