Graphene oxide/PVA inorganic/organic interpenetrating hydrogels with excellent mechanical properties and biocompatibility

In this article, graphene oxide (GO)/poly(vinyl alcohol) (PVA) inorganic/organic interpenetrating network (IPN) hydrogels with excellent mechanical properties and biocompatibility were reported. The hydrogels were synthesized using a freeze-thaw method with a modified GO network, which was crosslinked by β-cyclodextrin aldehyde (β-CD-DA) to form an inorganic GO network (β-GO). The structure of the hydrogels was characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and scanning electron microscopy. The results from compression tests show that the compression modulus of β-GO/PVA hydrogels increased by 5.3-fold compared with pure PVA hydrogels at 3 mg ml−1 β-GO. The results of the tensile test showed a 2.5-fold increase in breaking elongation when the β-GO concentration reached 3 mg ml−1. In biological tests, the β-GO/PVA hydrogels showed cytotoxicity levels as low as those of pure PVA hydrogels and controls. These results demonstrated that β-GO/PVA hydrogels could be promising substitutes for artificial articular cartilage.