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Abstract Various types of ceramic, polymer and bio-nanocomposite scaffolds have been used in laboratory and animal studies for bone tissue engineering. Pore size, chemical composition, and cell proliferation assay of biomaterials play an important role in the bone formation in in vitro and in vivo tests. In the current work, the titanium oxide (TiO 2) nanoparticles are added to nanoclay (NC) and composed with NaCl microparticles to build a porous scaffold using space holder technique. Then, the biomechanical, surface properties, and biological response of the samples are monitored to check the morphological, thermal, cell behavior and biological behavior of the manufactured bio-nanocomposite scaffolds using scanning electron microscopy (SEM), fourier transform infrared (FTIR), atomic force microscopy (AFM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. The obtained results show that the minimum requirement for the pore size is considered less than ∼100 nm due to the cell size, migration requirements and transport of the alive cell. However, pore sizes higher than ∼65–100 nm are supported in order to enhance the formation of the tissue in the biological environment such as simulated body fluid (SBF) and physiological saline (PS) as well as excellent capillaries formation. The resulting porosity is obtained without using porosity agents, and it is found that the holes are related to dimensions within the range of 60–82% and 55–75% for the samples soaked in the SBF and PS after 21 days, respectively. Also, it is revealed that the fracture toughness and compressive strength values of the samples are within the range of 0.66–0.89 MPa m1/2 and 4.5–5.7 MPa, respectively. Additionally, based on the extracted mechanical properties of the bio-nanocomposite scaffold, the nonlinear resonance response of a beam-type bone implant under soft and hard excitations is predicted analytically corresponding to the both subharmonic and superharmonic ranges. The bio-nanocomposite scaffold containing 15 wt% TiO 2 represents proper cell viability and cultured cell which prove the cytocompatibility of the fabricated NC-TiO 2 -NaCl scaffolds. Highlights • Fabrication a new bio-nanocomposite scaffold using the space holder technique. • Prediction the mechanical and biological characteristics of TiO 2 -Nanoclay composites. • Performing scanning electron microscopy, Fourier transform infrared analyses. • Conducting atomic force microscopy, X-ray diffraction, scanning calorimetry analyses. • Resonance analysis for a beam-type implant made of TiO 2 -Nanoclay composites. [ABSTRACT FROM AUTHOR]

Abstract Post-surgical infection is one of the essential problems in bone scaffolds that is usually treated with antibiotics. This issue may be related to the poor blood supply for bone tissue due to high concentrations of drug. In the current study, the effect of zinc oxide (ZnO) nanoparticles on the antibacterial behavior of the nanocrystalline hydroxyapatite (n-HA) scaffolds coated by gelatin-ibuprofen (GN-IBO) is evaluated. To this end, the bio-nanocomposite scaffolds are fabricated via the space holder technique and then characterized with the aid of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The compressive strength, fracture toughness, porosity, elastic modulus as the mechanical properties, and the apatite formation, biodegradation, drug release and wettability beside the roughness as the biological properties are predicted. The obtained experimental results indicate that the bio-nanocomposite scaffolds containing 10 wt% ZnO has suitable mechanical and biological properties. After that, an analytical model is developed to predict the nonlinear instability and vibration responses of an axially loaded sandwich plate-type implants made of the fabricated n-HA-ZnO bio-nanocomposites coated by GN-IBO thin film corresponding to various weight fractions of ZnO nanoparticles. It is found that ZnO peaks in the positions of 2θ are equal to 31.6 ° , 33.6 ° , 34 ° , 46.4 ° , and 62 ° , which represent the crystalline characteristics. Also, it is revealed that through addition of ZnO nanoparticles, the hardness and elastic modulus as well as the bone formation and biodegradation rate of the bio-nanocomposite scaffold enhance, while its drug release in the phosphate buffer solution detected with UV spectrum reduces. It is found that by increasing the ZnO weight fraction, the critical axial buckling load of the sandwich bio-nanocomposite implant enhances, and it buckles at lower axial shortening. However, it is seen that for higher value of wt% ZnO, its influence on the critical buckling load decreases. [ABSTRACT FROM AUTHOR]