Fabrication and characterization of electroconductive/osteoconductive hydrogel nanocomposite based on poly(dopamine-co-aniline) containing calcium phosphate nanoparticles

Abstract

This study aimed to integrate the unique benefits of electroconductive hydrogel scaffold and hydroxyapatite (HAp) crystals in the repair of bone defects. For this objective, HAp crystals were synthesized and dopamine-aniline copolymer (PDA-co-PANI) were synthesized through a chemical oxidation polymerization approach followed by its functionalization using maleic anhydride (MA), and finally, hydrogels were fabricated from different concentrations of copolymer/HAp by a free radical polymerization method. Size, zeta, NMR, FTIR, SEM, EDX, water absorption tests, blood compatibility, and cell studies were performed and the results were presented. The size and Zeta potential showed that the synthesized HAp has a hydrodynamic size of 1.96 µm and a zeta potential of −13.5 mV and the surface modification with MPS silane coupling agent reduced the size and zeta potential of crystals to 1.38 µm and −6.2 mV, respectively. The results showed that the prepared hydrogel possesses the electrical conductivity of 1.74 × 10–4 S/cm and incorporation of HAp crystals did not compromise the electrical conductivity. The fabricated scaffolds were compatible with bone cells (MG-63) and in vitro studies revealed that the scaffolds were good substrates for bone cell growth and are effective for repairing bone lesions.