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.