Biocompatible and photoluminescent carbon dots/hydroxyapatite/PVA dual-network composite hydrogel scaffold and their properties

Fluorescence imaging in vivo can non-invasively monitor and reveal the process of the implants. In this work, it has developed a novel Carbon dots/Hydroxyapatite/PVA (CDs/HA/PVA) dual-network (DN) hydrogel scaffold with excellent fluorescence and biocompatible properties, which have significant importance as implant biomaterials with the demands for less invasive procedures. The composite hydrogel was fabricated by two combined procedures, including firstly chemical crosslinking then physical crosslinking techniques. The composite hydrogel was further characterized by HRSEM, TGA and fluorescence spectrum et al. The results showed that the polymer networks of the CDs/HA/PVA DN hydrogel became more compact and their pore sizes decreased to about 1~3 μm after suffered the freezing/thawing cyclic process. When the mass ratios of CDs to PVA increased from 0.0% to 6.0%, they also exhibited a prominent enhancement of the maximum fluorescence emission intensities. What’s more, the CDs/HA/PVA DN hydrogels had excellent biocompatibility as MC3T3-E1 cells exhibited highly cell viabilities on their surfaces, the relative cell viability was about 91.24% after the MC3T3-E1 cells were incubated with the hydrogels for 5 days. This fluorescence-related hydrogel has potential to be applied in non-invasive monitoring field for the in vivo evaluation of implant biomaterials.