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One of the most critical challenges in tissue engineering is the fabrication of porous scaffolds with high porosity and proper mechanical properties. Conventional synthetic scaffolds are typically made of ceramic composed with other ceramics; however, a better combination of nanocomposite can be obtained using magnetite nanoparticles (MNPs), which benefits both ceramic materials. The current study used the space holder method and mechanical activation to create a porous magnetic-zirconia calcium bio-nanocomposite scaffold for bone tissue applications. The samples were made with varying amounts of reinforcement (0, 5, 10, and 15 wt%). The addition of sodium chloride has the main effect on the porosity size of the architecture. The prepared magnetic-zirconia calcium bio-nanocomposite scaffold was coated with a 5% solution of chitosan polymer, and its mechanical and biological properties were investigated. Powders and scaffolds were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. The cell viability and non-toxicity of porous scaffolds were evaluated by MTT assay. The results showed that the addition of 15 wt% of MNPs changed the mechanical and biological properties of the composite scaffold. According to the SEM results, addition of 15% MNPs did not significantly change the porosity. However, it improves the porosity percentages. After being placed in the simulated body fluid (SBF), SEM images of the scaffolds showed the formation of a bone-like apatite layer on the surfaces of the sample with a higher amount of MNPs. Biocompatibility assessment by MTT test showed that composite scaffolds did not show any toxicity in contact with bone marrow stem cells and increased cell growth and proliferation. The mechanical simulation shows that the specimen's mechanical strength can be predicted by low error and can be a suitable option for bone tissue engineering applications.

Due to the vital functions of bone tissue in the body, any change in its structure affects the balance of the body. Following a lesion, the body may be unable to repair it, and bone scaffolds may be implanted to stimulate bone cells and thus repair lost bone. This article aims to develop a scaffold with ideal properties that can be used to treat fractures and injuries. The technique used in this study is a hybrid of 3D printing and freeze-drying. Alginate (ALG), polyvinyl alcohol (PVA), and bioceramic-titanium nanoparticles were used to coat electroconductive polylactic acid (EC-PLA) using the freeze-drying method. The prepared samples were analyzed using a scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) for morphology functional group and phase characterizations. After coating the scaffolds with the freeze-drying method, the pore size was examined and correlated with the compressive strength values. For biological studies, a bioactivity test involving immersion of the samples in simulated body fluids (SBF) was performed for a specified period. The samples were then evaluated for water absorption, weight loss, and pH changes. Cell behavioral and antibacterial tests were performed to evaluate the growth of scaffolds in the body. Additionally, the compressive strength test results are incorporated into simulation and modeling analyses under static loading and micromechanical models. Finally, the circle-shaped scaffold containing titanium sample was chosen as a suitable scaffold due to its 78% porosity, 27% apatite formation, 75° wetting angle, 15% weight loss after 7 days, and 99% biocompatibility. Finally, the bio-nanocomposite scaffold can attach to the cell and then gradually degrade, preserving the implant's mechanical properties for the regeneration process.

In recent decades, polymer composites are widely used in industry due to their good mechanical properties and their low specific weight. Also, the use of glass fibers and carbon nanotubes can strengthen and improve the mechanical performance of the polymer due to their good mechanical properties. In this study, incorporated glass/epoxy nanocomposite with carbon nanotubes (CNT) samples were fabricated using a hand lay-up process, and the effect of addition functionalized Single-Walled Carbon Nanotubes (F-SWCNT) with COOH and non-functionalized SWCNT was investigated. The tensile strength, elastic modulus, bending strength was obtained experimentally using SANTAM-STM50. X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were used to investigate the phase and morphology of the fibers. The mechanical properties results showed that the highest elastic modulus and tensile strength are obtained for the sample reinforced with F-SWCNT which increased by 32% and 10%, respectively in comparison with pure epoxy. Also, the obtained results of the bending test indicate that the highest flexural modulus and the highest flexural strength are related to the sample reinforced with functionalized carbon nanotubes which are 16.9 GPa and 381.39 MPa, respectively. Then, the mechanical performance of the reinforcement in the epoxy matrix and the failure mechanism was monitored using SEM images. Finally, reinforced epoxy nanocomposites with functionalized and non-functionalized SWCNT were simulated using Molecular Dynamics (MD) simulation to examine the agreement with the trends of experimental results. The MD obtained results showed that the most appropriate mode of dispersion occurs when functionalized carbon nanotubes are used. Also, it was observed that the elastic modulus of incorporated nanocomposites with F-SWCNT increased by 17% compared to non-functionalized SWCNT which shows the agreement with the trends of experimental results.

In this work, a novel porous bio-nanocomposite material containing the commercial nanocrystalline hydroxyapatite (n-HA) composed using single-walled carbon nanotubes (SWCNTs) with different weight fractions (0, 2.5, 5, and 7.5 wt%) is fabricated via a space holder technique for bone tissue engineering applications. The hydroxyapatite (HA) presents a weak mechanical performance which the addition of the SWCNT can enhance the mechanical strength of the matrix. The manufactured n-HA-SWCNT bio-nanocomposite samples are then coated by gelatin-ibuprofen (GN-IBO) bio-polymer with a dip-coating method. The X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) are employed for the phase characterization and surface morphology analysis of the fabricated bio-nanocomposite specimens. The mechanical properties, the rate of drug release, and biological characteristics of the specimens with and without SWCNTs are investigated. After that, the nonlinear instability and vibration responses of an axially loaded plate-form bone implant made of the manufactured n-HA-SWCNT bio-nanocomposite samples coated with GN-IBO thin layers are simulated through a sandwich-plate model and based upon the experimentally extracted mechanical properties. The obtained results indicate the presence of SWCNT and n-HA in the composition due to the fuzzy metamorphism or degradation. It is found that by increasing the amount of SWCNTs, the mass density of the fabricated bio-nanocomposite samples reduces, but the porosity and strength of them are higher than those of the pure n-HA. Therefore, it is expected that these newly manufactured bio-nanocomposites have an excellent capability for bone formation with better bonds with surrounding tissues.

Bone regeneration is a growing and relatively effective treatment in most bone disease treatments. Adverse effects associated with conventional transplantation techniques have led to advanced bone tissue engineering. The purpose of this study is to produce a bone scaffold, made of sodium alginate (Na-Alg) based scaffold, with the addition of wollastonite-graphene nanosheet (WS-GS) with similar mechanical properties to normal bone. First, the Na-Alg-WS-GS nanocomposites are fabricated using freeze-drying technique in which GS is used as additives with different weight percentages (0, 1, 2 and 3 wt%). The fabricated nanocomposite scaffolds are tested and analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyzes. The maximum tensile strength, lowest decrease in sample area and stress yield is tested using mechanical testing. Then, the biological response in the biological environment, pH and weight changes after immersion in simulated body fluid (SBF) and phosphate buffered saline (PBS) is determined. The results show that the sample with 1 wt% GS has an appropriate capacity for reconstitution in the biological solution. The SEM shows an appropriate porosity of the scaffolds and a uniform distribution of GS in the polymeric matrix. The SEM images shows that as the amount of GS increases, the swelling capacity of the nanocomposites rises, regarding the weak bonding of GS and polymeric matrix. Additional amount of GS leads to increase in the tensile strength with the sample containing 1 wt%, however increasing of GS may decreases the mechanical performance of the structure. To gain the optimal combination of scaffold with the best mechanical and biological properties, the Global Criterion Method (GCM) is utilized. The obtained results show that the prepared nanocomposites are suitable for further development in tissue engineering and can be suitable for the bone substitutes application with desirable mechanical performance.

The multiscale nanocomposites are a new class of the designed materials that have nano and micro-scale reinforcements. The main purpose of this paper is to investigate the mechanical properties suc...

Scaffold creates a chance for bone growth and facilitates cell adhesion, growth and differentiation in orthopedic surgeries. Designing scaffold with adequate porous geometry and suitable compressive strength is debatable among biomaterial engineers and clinical orthopedic surgeons. Therefore, in this study we fabricate a novel porous hydroxyapatite-wollastonite reinforced with 0, 5, 10, and 15 wt% alumina nanoparticles (ALN: 40–80 nm) for bone substitute. In the current work, a porous cylindrical scaffold (6 mm × 10 mm) fabricated with space holder (SH) technique using sodium bicarbonate (NaHCO3) as a porous agent. The porosity, compressive strength and the biological behavior of the porous samples were investigated using standard mechanical and biological testing. After making the specimen, scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis were performed to verify the accuracy of the nanomaterial's properties. The mechanical and biological analysis (swelling & water absorption) showed that the sample with 10 wt% alumina nanoparticles (ALN) had both proper compression strength vs. porosity percentage and bioactivity response. The molecular modeling for predicting the elastic modulus of bio-nanocomposite were performed and the results were close to the experimental values. The obtained result, indicated that compressive strength increased from 2.8 to 3.5 MPa with 49% to 61% porosity value. The sample with 10 wt% ALN and wollastonite showed clinical applications of these composites as a bone-substitute.

In the current study, hydroxyapatite (HA)-MgO scaffolds are fabricated with the aid of the space holder technique using NaCl as the spacer type. After that, the fabricated samples are deposited in gelatin (GN) with ibuprofen (IBO) substitution to create GN-IBO thin surface coating. The samples are then synthesized chemically and the associated properties are studied using X-ray diffraction (XRD) and scan electron microscopy (SEM) equipped with the energy dispersive spectroscopy (EDS). The compressive strength, fracture toughness, hardness, porosity, bioactivity, degradation rate, wettability, and roughness of the manufactured HA-MgO bio-nanocomposite scaffolds containing different weight fractions of MgO nanoparticles are predicted. Accordingly, nonlinear mechanical behaviors including nonlinear free vibration and nonlinear vibrations associated with the prebuckling and postbuckling domains of an axially loaded plate-type bone implant made of the HA-MgO bio-nanocomposites coated with the GN-IBO thin layers are investigated analytically via a sandwich plate model. The obtained results reveal that magnesium has no considerable effect on the porosity, however it causes to enhance the compressive strength significantly. The presence of magnesium ions also leads to reduce the crystallinity of HA about 30–100 nm due to entering MgO nanoparticles into the network. The results related to the sample with 10 wt% MgO nanoparticles indicate that the microscopic structure of the fabricated bio-nanocomposite scaffold is three-dimensional with porous architecture. Also, it is shown that the solubility of the HA composed with MgO nanoparticles decreases with higher bioactivity.

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 (TiO2) 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% TiO2 represents proper cell viability and cultured cell which prove the cytocompatibility of the fabricated NC-TiO2-NaCl scaffolds.

properties such as biocompatibility and proper bioactivity response. The aim of the present study was to investigate the bioactivity of wollastonite-hydroxyapatite (WS-HA) bio-nanocomposite for the treatment of orthopedic prosthesis coatings approaches by adding magnetic nanoparticles (Fe3O4; MNPs) and single walled carbon nanotubes (SWCNTs) to the matrix. Bio-nanocomposite coated on AZ91 for 40 minutes at 40 volts using electrophoretic deposition (EPD) and after that the heat treatment performed at 550-650°C for 1 hour. The coats were incubated in simulated body fluid (SBF) and phosphate buffer saline (PBS) for 28 days to detect and confirm apatite-like layer formation. X-ray diffraction (XRD), atomic force microscope (AFM) and scanning electron microscopy (SEM) techniques were used to characterize the phase and morphology of the coated sample. Inductively coupled plasma optical emission spectroscopy (ICP-AES) tests were used to evaluate the concentrations of calcium and silicon ions. The finding from the present study showed the successful coating with 10 wt% MNPs added to the WS bio-nanocomposite with proper biological and chemical properties. Bio-nanocomposite coating can be considered as a suitable candidate for orthopedic coating applications due to its favorable bioactivity.

In the present work, bioactive nanoclay-TiO2 (NC-T) bio-nanocomposite scaffolds containing different TiO2 weight fractions are fabricated spacer for bone tissue engineering applications via the space holder technique using NaCl particles as the. The microstructure, surface morphology (porosity) and bioactivity potential of the manufactured bio-nanocomposite scaffolds are examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), energy dispersive spectroscopy (EDS), and inductively-coupled plasma optical emission spectroscopy (ICP-OES) techniques. The scaffold with optimized mechanical properties is predicted as NC-15wt%T with proper interconnected porosity and micro/macro pore size within the range of 1–2 (μm) and 3–5 (μm), respectively. Also, its mechanical properties including compressive strength, elastic modulus and crystallite size are extracted equal to 5.74 MPa, 438 MPa and 70–120 nm, respectively. The feasibility of the fabricated scaffolds for bioactive bone tissue engineering application (apatite deposition) is also evaluated using simulated body fluid (SBF) and physiological saline (PS) solutions. At the end, the nonlinear bending and vibration characteristics of an axially loaded beam-type bone implant made of the NC-T/NaCl bio-nanocomposite scaffolds are predicted analytically. In general view, the obtained results indicate that the NC-15wt%T/NaCl bio-nanocomposite scaffold may have excellent advantages for future research in bone regenerative applications.

Having excellent biocompatibility and apatite mineralization as well as efficient mechanical properties makes bredigite as one of the most attractive bioceramics. A beam-type porous biological implant in a 3D-printed architecture is designed with micron pore size. The surface properties, morphology, and size of the composed powders are evaluated using Scherrer and Williamson-Hall equation. The effect of MNPs deposition into the bredigite bioceramics and correlation with temperature effect on roughness of the prepared bio-nanocomposite are also investigated for hyperthermia application potential. The composed powders are characterized by x-ray diffraction, and then scanning electron microscopy (SEM), differential scanning calorimetry, thermogravimetric analysis (weight change, TGA), and atomic force microscopy are utilized to evaluate the surface topography. The resonance response is the tendency of a bone scaffold to respond at prominent amplitude while the frequency of its oscillations is equal to the structure’s natural frequency of vibration. Therefore, based on the obtained mechanical properties via the experimental approach for the bio-nanocomposite material, an analytical solution based upon the multiple-timescale method is carried out to analyze the nonlinear primary resonance of a 3D-printed porous beam-type biological implant under uniform-distributed load. According to SEM observations, there are hard agglomerates in the bredigite-magnetite nanoparticles (Br-MNPs) bio-nanocomposite material with low weight fraction of MNPs. However, they are broken down by increasing the amount of MNPs. Also, it is displayed that for lower MNPs weight fraction, the height of jump phenomenon related to the nonlinear resonance response is maximum and minimum for, respectively, irregular and mesoporous shapes of morphology, but their associated forcing amplitudes related to the bifurcation points are minimum and maximum, respectively.

Due to the Si-O-Si bonding, silicate bioceramics have enhanced mechanical characteristics than their calcium phosphate (CaP) counterparts. Bredigite with orthorhombic crystal system is one of the most efficient bioceramics in osteoblast and bone growth. On the other hand, biosilicate-magnetite composites (e.g. bredigite-magnetite and hardystonite-magnetite) are excellent candidates for hyperthermia applications. In the current study, the vibrational response of a beam-type bone implant subjected to axial compression is investigated. The implant is made of bredigite-magnetite bio-nanocomposite scaffold fabricated by 3D printing machine including 0.8 mm pore size. The Young's modulus of the scaffold is extracted experimentally corresponding to different magnetite nanoparticle (MNP) weight fractions, crystalline nanocomposite particle size, and various shapes of morphology. The morphology shape is determined corresponding to different MNP weight fractions and temperatures using scanning electron microscopy (SEM). Thereafter, an analytical solution is presented to express explicitly the load-frequency and frequency-deflection responses of the axially loaded beam-type bone implant. It is observed that in the prebuckling domain, by increasing the axial compressive load, the influence of the MNP weight fraction on the natural frequency of the bio-nanocomposite implant increases while in the postbuckling regime, increment in the axial compression has no effect on the significance of the MNP weight fraction effect.

The aim of the present study was to study the mechanical and biologocal properties of the bredigite-magnetite (Ca 7 MgSi 4 O 16 -Fe 3 O 4 ) nanocomposite with various amounts of magnetite (0, 10, 20 and 30 wt. %). According to the obtained results, the properties of the constructed scaffolds have an extreme dependence on the magnetite content. In this research, the bredigite-30wt. % magnetite as the optimum sample showed a fracture toughness of 2.69 MPa m 1/2 and a Young's modulus of 29 GPa. Increasing bredigite content led to the increase of pH values in the SBF solution. This was originated from the interchange/interaction of Ca 2+ ion on the scaffold surface. The sample containing 10 wt. % magnetite presented a rocky and irregular surface while that of 30 wt.% illustrated a smooth and flat outer layer with coarse projections. The results confirmed that the biodegradation rate of the pure bredigite is more than that of 20 wt.% sample. The event is originated from the dissolution of the Si ions of the bridigite particles in the absence of magnetite.

Although, the ideal hard ferromagnetic particles are much better energy absorbers as against the ideal superparamagnetic particles, the use of hard ferromagnetic materials in hyperthermia applications has always been a major challenge for researchers due to their high anisotropy. This work introduces a route to use a hard magnetic material (SrFe12O19) in the form of nanoparticle and scaffold in hyperthermia application. Single domain SrFe12O19 nanoparticles, with a hard magnetic behavior, when composited with hydroxyapatite (HA), allowed the use of the minimum frequency and amplitude of the alternative magnetic (AC) field to have high amount of specific absorption rate. This was the outstanding advantages of this work, especially when a monodispersed HA-SrFe12O19 nanocomposite was used. HA-10 wt%SrFe12O19 scaffolds, after gelatin coting, showed a high stable compressive strength with a high uniform interconnected porosities. Besides, HA-10 wt%SrFe12O19 composite nanoparticles showed a high specific absorption rate in both mono and multi dispersed states.

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. The use of calcium silicate coatings has extensively increased due to properties such as biocompatibility and proper bioactivity response. The present study was aimed to investigate the bioactivity of wollastonite-hydroxyapatite (WS-HA) bio-nanocomposite for the treatment of orthopedic implant coatings by adding magnetic nanoparticles (MNPs) and single-walled carbon nanotubes (SWCNTs) to the matrix. The bio-nanocomposite was coated on Mg substrate for 40 min at 40 V using electrophoretic deposition (EPD), following which the heat treatment was performed at 550–650 °C for 1 h. The coatings were incubated in simulated body fluid (SBF) and phosphate buffer saline (PBS) for 28 days to detect and confirm apatite-like layer formation Inductively coupled plasma-optical emission spectroscopy (ICP-OES) was used to evaluate the concentration of calcium and silicon ions.

The aim of this study is to evaluate the hyperthermia application of a novel bredigite-magnetite nanocomposite for bone tissue engineering. Magnetite nanoparticles were synthesized by the co-precipitation method and then composited with bredigite powders via a mechanical milling route and subsequent sintering process. Bredigite-Magnetite nanocomposite possessed a homogeneous dispersion of magnetite nanoparticles, which was confirmed by the absence of large aggregates. To evaluate the heat release of the composite nanoparticles, an alternating magnetic (AC) field was applied. The results showed an increase in the temperature, as a result of the increasing magnetite concentration. The sample containing 30 wt.% magnetite particles showed a temperature increase about 27 °C during 50 s. Generally, the present work confirmed that the bredigite-magnetite nanocomposite can be considered as an assuring candidate in hyperthermia applications.

Biopolymer scaffolds have received great interest in academic and industrial environment because of their supreme characteristics like biological, mechanical, chemical, and cost saving in the biomedical science. There are various attempts for incorporation of biopolymers with cheap natural micro- or nanoparticles like lignin (Lig), alginate, and gums to prepare new materials with enhanced properties. Materials and Methods: In this work, the electrospinning (ELS) technique as a promising cost-effective method for producing polymeric scaffold fibers was used, which mimics extracellular matrix structure for soft tissue engineering applications. Nanocomposites of Lig and polycaprolactone (PCL) scaffold produced with ELS technique. Nanocomposite containings (0, 5, 10, and 15 wt.%) of Lig were prepared with addition of Lig powder into the PCL solution while stirring at the room temperature. The bioactivity, swelling properties, morphological and mechanical tests were conducted for all the samples to investigate the nanocomposite scaffold features. Results: The results showed that scaffold with 10 wt.% Lig have appropriate porosity, biodegradation, minimum fiber diameter, optimum pore size as well as enhanced tensile strength, and young modulus compared with pure PCL. Degradation test performed through immersion of samples in the phosphate-buffer saline showed that degradation of PCL nanocomposites could accelerate up to 10% due to the addition of Lig. Conclusions: Electrospun PCLLig scaffold enhanced the biological response of the cells with the mechanical signals. The prepared nanocomposite scaffold can choose for potential candidate in the biomedical science

One of the most common fractures in the skeleton happens in the femur. One of the important reasons for this fracture is because it is the longest bone in the body and osteoporosis affect this part a lot. The geometric complexity and anisotropy properties of this bone have received a lot of attention in the orthopedic field. In this research, a femur designed using 3D printing machine using the middle part of the hip made of polylactic acid–hydroxyapatite (PLA–HA) nanocomposite containing 0, 5, 10, 15, and 25 wt% of ceramic nanoparticle. Three different types of loadings, including centralized loading, full-scale, and partially loaded, were applied to the designed femur bone. The finite element analysis was used to analyze biomechanical components. The results of the analysis showed that it is possible to use the porous scaffold model for replacement in the femur having proper strength and mechanical stability. Stress–strain analysis on femoral implant with biometric HA and PLA after modeling was performed using the finite element method under static conditions in Abaqus software. Three scaffold structures, i.e., mono-, hybrid, and zonal structures, that can be fabricated using current bioprinting techniques are also discussed with respect to scaffold design.

In the current study, bio-nanocomposites scaffolds including natural hydroxyapatite (n-HA) composed with different weight fractions of copper oxide nanoparticles (CuO-NPs) are fabricated using the space holder technique. After that, the manufactured samples are coated with gelatin polymer loaded with ibuprofen drug. Via experimental methods, the mechanical properties (fracture toughness and compressive strength) of n-HA-CuO bio-nanocomposite scaffolds are achieved corresponding to various weight fractions of the CuO-NPs. Also, the electrical conductivity and cell viability of the fabricated scaffolds are evaluated using the scan electron microscope (SEM) and X-ray diffraction (XRD) technique. Thereafter, based upon the extracted mechanical properties, nonlinear mechanical behaviors of beam-type implants made of the prepared n-HA-CuO bio-nanocomposites are predicted analytically. The cell viability and electrical conductivity evaluation demonstrate that on the free surface of all bio-nanocomposite scaffolds, there is a thin layer of apatite carbonate; however, the thickness of this layer in the sample containing 5wt% CuO-NPs is lower than other ones. It is seen that the adherence of ibuprofen's penetration into the gelatin polymer is weak which leads to two explosive release stages. For the lower weight fraction of CuO-NPs, the release of ibuprofen becomes significant.

In order to achieve more efficient additive materials having precise desired porosities with excellent performance, advanced manufacturing techniques can be put to use. In the present study, 3D printing technology is employed to fabricate mesoporous bioceramic-based bony scaffolds made of various periodic cellular topologies including cubic, cylindrical and hexagonal porosity configurations. The samples are composed of polylactic acid-hydroxyapatite (PLA-HA) mesoporous bioceramic-based nanocomposites. Via the respective experiments, the mechanical properties of the fabricated bony scaffolds are extracted corresponding to each porosity configuration with different pore sizes. Moreover, by using the scanning electron microscopy (SEM), X-ray diffraction (XRD) and the permeability characteristics of the fabricated bio-composite samples after soaking in the simulated body fluid (SBF) are captured. Thereafter, based on the experimentally obtained mechanical properties, the multiple time-scales method is utilized to develop an analytical solution for the nonlinear secondary resonance of PLA-HA mesoporous beam-type implants under subharmonic and superharmonic excitations. The frequency-response and amplitude response associated with the both types of hard excitations are depicted corresponding to different periodic cellular topologies and pore sizes. It is observed that among various periodic cellular topologies, the gap between two branches of the subharmonic frequency-response associated with the cubic and hexagonal ones is maximum and minimum, respectively. In the case of superharmonic excitation, it is found that through reduction of the pore size, the peak of frequency-response and its associated value of the detuning parameter decrease.

The aim of the present study is to prepare the bovine hydroxyapatite-diopside (bHA-Di) nanocomposite coating using electrophoretic deposition (EPD) technique and then investigation of the bioactivity, wettability and hardness of the produced coating samples at different percentage of Di. For this purpose the HA powders is prepared from the bovine bones by a simple new method and then Di powders that have already synthesized by the use of mechanical milling method, is injected into the HA matrix. At the end a suspension of the bHA-Di nanocomposite is created and coated on the titanium (Ti) implants by the EPD technique. The sintered nanocomposite coating are then sintered and analysed. X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC), energy dispersive spectroscopy (EDS) and inductive coupled plasma atomic emission spectroscopy (ICP-AES) are used as instruments for gathering and analysing the experimental results. According to the results obtained, the produced composite coating with 30 wt. % Di has favourable bioactivity, good wettability and high hardness.

Introduction: Advantages of using porous bio-nanocomposite scaffolds for maxillofacial fracture application and optimizing the internal surfaces of synthetic grafts using nanotechnology can accelerate the bone cell adhesion, mechanical properties and absorption rates. There are various studies that have been performed on porous scaffold, especially for the fractured and destroyed parts of the facial bones. The aim of this study was to investigate the experimental and numerical analysis of the porous scaffold, which undertakes static and dynamic loading conditions. Materials and Methods: The maxillofacial bone was modeled using the solid works software, and then it was inserted into the Abaqus software to achieve a more precise model that utilizes an isotropic linear substance. Thereafter, a proper micromechanical model reported evaluating the elastic modulus response on porosity value using various models. Additionally, an experimental analysis was conducted on a new calcium silicate (CS) bioceramic reinforced with magnetite nanoparticles (MNPs) using the space holder technique coated with the gentamicin drug loaded on gelatin polymer. The response of the bio-nanocomposites shape, which corresponds to different MNPs’ weight fractions, was determined using the scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. Results: The analysis of the scaffold implant showed that it is tightened at a torque of stiffness of 3 mm in the implant, which leads to high mechanical tension. The results showed that the elastic modulus of the nanocomposites increased from 60±5 MPa to 145±5 MPa with increasing 15 wt% MNPs to the calcium silicate nanoparticles. Conclusion: The results indicated that addition of 15 wt% MNPs to the based bioceramics increased both compression strength and decrease the porosity value.

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.

Iranian Gum Tragacanth (IGT) is among the most natural polymers which has interesting properties such as nontoxic nature, biodegradability and high resistance to bacterial attacks making it applicable for tissue scaffolds, protective clothing, and wound healing. In the current work, polyvinyl alcohol (PVA)/IGT nanocomposite fibre is prepared by using the electrospinning (ELS) technique in an aqueous solution with different volume ratios of 60/40, 70/30, 80/20, and 90/10. To enhance the chemical and mechanical stability of the produced samples, different amounts of nanoclay powder (1% and 3%) are added also to the solution. The blended nanofibres are characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and bioactivity evaluation in phosphate buffered saline (PBS) and simulated body fluid (SBF) solutions. The FTIR analysis indicated that PVA and IGT may have H + bonding interactions. The results revealed that with a higher amount of IGT, a superior degradation as well as a higher chemical and biological stability could be obtained in the nanobiocomposite blend fibres. Furthermore, the blend nanofibre samples of 80/20 and 3% nanoclay powder exhibit a significant improvement during evaluation of its properties.

Since hydroxyapatite-based materials have similar composition and crystallinity as natural calcified tissues, can be used for bone/tissue engineering. In the present study a novel nanocomposite based on bioceramics such as Natural Hydroxyapatite (NHA) and Baghdadite (BAG), was sintered by spark plasma sintering (SPS) technique. The prepared composite was characterized using scanning electron microscopy (SEM), X-ray diffractometer (XRD) and Brunauer–Emmett–Teller (BET) techniques. The porosity of the samples was measured by Archimedes method. The cold crushing strength (CCS) test was applied to evaluate their mechanical properties. Our results demonstrated that NHA-30wt. %BAG nanocomposite specimens have the lower CCS in comparison with other examined composites. Consequently, NHA/BAG samples exhibited acceptable mechanical properties and could be suitable candidates for bone tissue engineering applications especially orthopaedic fields.

In the present work, the releasing heat, scaffold apatite formation, and magnetic behavior of a novel diopside-magnetite nanocomposite with various contents of magnetite (Fe3O4) were evaluated. The N´eel and Brown relaxations did not have a significant effect on the specific absorption rate (SAR) of the composite samples. Indeed, magnetic saturation, Ms, indicated a crucial effect on the heat release of the samples. The sample with 30wt% magnetite had the highest value of SAR, while the sample with 20wt% magnetite, in the form of scaffold, allowed the high amount of apatite formation on its surface.

The surface characteristics of implant which influence the speed and strength of osseointegration include surface chemistry, crystal structure and crystallinity, roughness, strain hardening, and presence of impurities. The aim of this study was to evaluate the bioactivity and roughness of a novel natural hydroxyapatite/zircon (NHA/zircon) nanobiocomposite, coated on 316L stainless steel (SS) soaked in simulated body fluid (SBF). NHA/zircon nanobiocomposite was fabricated with 0 wt.%, 5 wt.%, 10 wt.%, and 15 wt.% of zircon in NHA using ball mill for 20 minutes. The composite mixture was coated on 316L SS using plasma spray method. The results are estimated using the scanning electron microscopy (SEM) observation to evaluate surface morphology, X-ray diffraction (XRD) to analyze phase composition, and transmission electron microscopy (TEM) technique to evaluate the shape and size of prepared NHA. Surfaces roughness tester was performed to characterize the coated nanocomposite samples. The maximum averageRa(14.54 μm) was found in the NHA 10 wt.% of zircon coating. In addition, crystallinity (Xc) was measured by XRD data, which indicated the minimum value (Xc = 41.1%) for the sample containing 10 wt.% of zircon. Maximum bioactivity occurred in the sample containing 10 wt.% of zircon, which was due to two reasons: first, the maximum roughness and, second, the minimum crystallinity of nanobiocomposite coating.