Boron nitride nanostructures reinforced nanohydroxyapatite: bifunctional nanocomposite for potential orthopedical use and ciprofloxacin controlled delivery

One of the most promising options for bone defects or lesions is the use of synthetic materials as bone substitutes. Thus, the objective of the present work was to synthesize a nanocomposite of HA and BNNS, as a reinforcement phase, to obtain a material with satisfactory mechanical properties as well as bifunctional, with the incorporation of ciprofloxacin to evaluate the potential of the system as a drug delivery. The nanocomposites obtained were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), nitrogen adsorption by BET and BJH methods, scanning electron microscopy (SEM) and electron microscopy transmission (TEM). The Vickers hardness test and nanoindentation showed an increase in the mechanical strength of the nanocomposites with the insertion of the reinforcement phase, thus corroborating the promising character of BNNS as a reinforcement agent for HA. A biocompatibility assay was performed to assess the potential of the samples as effective biomaterials. The nanocomposites showed high cell viability indicating that the system does not present cytotoxicity. Drug loading and in vitro release show that the system can provide rapid drug delivery, giving antibacterial effects at the infected site, indicating that the nanocomposite, a bioceramic, is suitable for the application.