Bone Tissue Engineering of HA/COL/GO Porous Nanocomposites with the Ability to Release Naproxen: Synthesis, Characterization, and In Vitro Study

In the present research, porous hydroxyapatite/collagen/graphene oxide (HA/COL/GO) nanocomposites were synthesized using the freeze-drying method for naproxen delivery. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) techniques were applied to analyze the synthesized specimens. In addition, the loading of naproxen and release behavior (pH 7.4 and T = 37 °C) of the prepared nanocomposites were studied via UV–Vis spectrophotometry. The FE-SEM analysis revealed that HA/COL/GO nano-composites had a rod-like structure and the morphological change in the HA/COL/GO nano-composites confirmed that graphene oxide (GO) sheets and HA/COL nano-particles were successfully incorporated where the nanocomposites were synthesized with size smaller than 50 nm. BET analysis was utilized to confirm the meso and macrostructure of specimens with an average pore diameter within 15–103 nm as well as the BET surface area of 21–178 m2/g. The application of synthesized samples for naproxen delivery in vitro was investigated. As the weight ratio of GO increased, so did the percentage of drug-loading; for the HA/COL/GO-3 sample where the graphene oxide (GO) amount was maximum, the percentage of drug loading capacity (LC%) and percentage of encapsulation efficiency (EE%) were obtained 38.7% and 84.8%, respectively. Naproxen release results in phosphate buffer saline (PBS) confirmed that the initial release occurred in all synthesized nanocomposites within the first 24 h, after which the release rate gradually declined to about 14 days. Under optimal conditions, the HA/COL/GO-3 sample retained about 39.2% of the loaded drug after 14 days, as some of the drug molecules were deeply embedded in the HA/COL/GO-3 sample. Furthermore, the results revealed that the degradation rates of the synthesized nanocomposites can be controlled by adjusting the amount of graphene oxide (GO). Thus, the results show that the samples synthesized in this research can suitable candidates for continuous release of naproxen and bone tissue engineering.