Ciprofloxacin-loaded chitosan-based nanocomposite hydrogel containing silica nanoparticles as a scaffold for bone tissue engineering application

Considering the nanocomposite structure of natural bone, three-dimensional (3D) nanocomposite hydrogels based on osteoconductive (nano-)materials and polymeric biomaterials are promising scaffolds in bone tissue engineering (TE). Therefore, a novel scaffold composed of chitosan (CS), poly(2-hydroxyethyl methacrylate) (PHEMA), and SiO2 nanoparticles (NPs) was fabricated for bone TE application. Firstly, SiO2 NPs were synthesized, and then modified. The modified NPs, CS, and HEMA monomer was copolymerized via free radical polymerization method in the presence of a crosslinker to afford a nanocomposite hydrogel (CS-cl-PHEMA/SiO2) followed by loading of ciprofloxacin (Cip) as an antibiotic drug. Drug encapsulation efficiency was obtained approximately 20% for the scaffold, and in vitro drug release study revealed that the scaffold had a pH-dependent drug release profile. Applicability of the scaffold in bone TE was examined in terms of numerous physicochemical and biological features. Maximum swelling of scaffold was obtained as 312% after 5 h, and then reached equilibrium. The scaffold exhibited proper in vitro biodegradation, especially in acidic pH. Hemolysis assay revealed that the scaffold was hemocompatible up to 400 mu gmL-1 with hemolytic rate of 4.9%. MTT-assay results revealed that the scaffold do not had any toxic effects on the cells and can improve the proliferation of osteoblast cells.