HA Powder Research Articles

Plate-shape carbonated hydroxyapatite/collagen nanocomposite hydrogel via in situ mineralization of hydroxyapatite concurrent with gelation of collagen at pH = 7.4 and 37°C.

The objective of this study was to develop a collagen/hydroxyapatite (HA) nanocomposite scaffold for bone tissue engineering applications. For this purpose, in situ mineralization of HA was accompanied with formation of collagen hydrogel at condition similar to the physiological condition, pH = 7.4, and 37°C. The physicochemical and biological properties of the in situ scaffold were compared with nanocomposite fabricated by mixing HA powder and collagen hydrogel (powder-mixed scaffold). The HA in this method was formed in the same condition as the in situ method. X-ray diffraction and FTIR analysis of in situ scaffold showed the formation of carbonated HA, similar to bone, while the HA powder in powder-mixed scaffold showed non-carbonated structure. Scanning electron microscopy revealed the formation of fibrillated collagen in both composites. HA was observed in both scaffolds, but with different morphology. The in situ formed HA had a plate-like morphology while the preformed HA showed spherical morphology in the powder-mixed scaffold. The in-vitro cytocompatibility and osteogenesis activity of scaffolds using osteoblast-like cells (MG-63) showed higher cytocompatibility and more osteogenesis capability of the in situ scaffold in comparison with the powder-mixed scaffold. The results suggest the in situ method as a proper approach for fabrication of HA/collagen scaffolds with similar properties like bone. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1920-1929, 2019.

Microstructure and mechanical properties of Ti-6Al-4V-5% hydroxyapatite composite fabricated using electron beam powder bed fusion

A novel, Ti-6Al-4V (Ti64)/Hydroxyapatite (HA at 5% by weight concentration) metal/ceramic composite has been fabricated using electron beam powder bed fusion (EPBF) additive manufacturing (AM): specifically, the commercial electron beam melting (EBM®) process. In addition to solid Ti64 and Ti64/5% HA samples, four different unit cell (model) open-cellular mesh structures for the Ti64/5% HA composite were fabricated having densities ranging from 0.68 to 1.12 g/cm3, and corresponding Young’s moduli ranging from 2.9 to 8.0 GPa, and compressive strengths ranging from ∼3 to 11 MPa. The solid Ti64/5%HA composite exhibited an optimal tensile strength of 123 MPa, and elongation of 5.5% in contrast to a maximum compressive strength of 875 MPa. Both the solid composite and mesh samples deformed primarily by brittle deformation, with the mesh samples exhibiting erratic, brittle crushing. Solid, EPBF-fabricated Ti64 samples had a Vickers microindentation hardness of 4.1 GPa while the Ti64/5%HA solid composite exhibited a Vickers microindentation hardness of 6.8 GPa. The lowest density Ti64/5%HA composite mesh strut sections had a Vickers microindentation hardness of 7.1 GPa. Optical metallography (OM) and scanning electron microscopy (SEM) analysis showed the HA dispersoids to be highly segregated along domain or grain boundaries, but homogeneously distributed along alpha (hcp) platelet boundaries within these domains in the Ti64 matrix for both the solid and mesh composites. The alpha platelet width varied from ∼5 μm in the EPBF-fabricated Ti64 to ∼1.1 μm for the Ti64/5%HA mesh strut. The precursor HA powder diameter averaged 5 μm, in contrast to the dispersed HA particle diameters in the Ti64/5%HA composite which averaged 0.5 μm. This work highlights the use of EPBF AM as a novel process for fabrication of a true composite structure, consisting of a Ti64 matrix and interspersed and exposed HA domains, which to the authors’ knowledge has not been reported before. The results also illustrate the prospects not only for fabricating specialized, novel composite bone replacement scaffolds and implants, through the combination of Ti64 and HA, but also prospects for producing a variety of related metal/ceramic composites using EPBF AM.

Physical-mechanical characterization of biodegradable Mg-3Si-HA composites

Purpose Porous implant surface is shown to facilitate bone in-growth and cell attachment, improving overall osteointegration, while providing adequate mechanical integrity. Recently, biodegradable material possessing such superior properties has been the focus with an aim of revolutionizing implant’s design, material and performance. This paper aims to present a comprehensive investigation into the design and development of low elastic modulus porous biodegradable Mg-3Si-5HA composite by mechanical alloying and spark plasma sintering (MA-SPS) technique. Design/methodology/approach This paper presents a comprehensive investigation into the design and development of low elastic modulus porous biodegradable Mg-3Si-5HA composite by MA-SPS technique. As the key alloying elements, HA powders with an appropriate proportion weight 5 and 10 are mixed with the base elemental magnesium (Mg) particles to form the composites of potentially variable porosity and mechanical property. The aim is to investigate the performance of the synthesized composites of Mg-3Si together with HA in terms of mechanical integrity hardness and Young’s moduli corrosion resistance and in-vitro bioactivity. Findings Mechanical and surface characterization results indicate that alloying of Si leads to the formation of fine Mg2 Si eutectic dense structure, hence increasing hardness while reducing the ductility of the composite. On the other hand, the allying of HA in Mg-3Si matrix leads to the formation of structural porosity (5-13 per cent), thus resulting in low Young’s moduli. It is hypothesized that biocompatible phases formed within the composite enhanced the corrosion performance and bio-mechanical integrity of the composite. The degradation rate of Mg-3Si composite was reduced from 2.05 mm/year to 1.19 mm/year by the alloying of HA elements. Moreover, the fabricated composites showed an excellent bioactivity and offered a channel/interface to MG-63 cells for attachment, proliferation and differentiation. Originality/value Overall, the findings suggest that the Mg-3Si-HA composite fabricated by MA and plasma sintering may be considered as a potential biodegradable material for orthopedic application.

Optimization of Hydroxyapatite Synthesis and Microplasma Spraying of Porous Coatings Onto Titanium Implants

Abstract The paper presents the main results of development and optimization of the synthesis of hydroxyapatite and the application of the micro-plasma spraying technique for biocompatible coatings. The hydroxyapatite synthesis was optimized using the mathematical modelling method. Synthesized hydroxyapatite was studied by IR spectrometry and X-ray diffraction analysis for assessment of the compatibility of the chemical and phase composition to the bone tissue. The Ca/P ratio of the obtained hydroxyapatite was 1.65, which is close to that of bone tissue (1.67). To increase the adhesion strength of the HA coating to the surface of the titanium implant, it was suggested to apply a titanium sublayer to the implant surface. Microplasma spraying (MPS) of biocompatible coatings from titanium wires and synthesized HA powders onto substrates made of medical titanium alloy has been carried out. Microplasmatron MPN-004 is used to obtain the two-layer coatings for titanium implants. The two layer coating includes a sub-layer of a porous titanium coating with a thickness in range from 200 up to 300 μm and the porosity level of about 30%, and an upper layer of HA about 100 μm thick with 95% level of HA phases and 93% level of crystallinity. The pore size varies from 20 to 100 μm in both coatings. The paper describes the technology and modes of microplasma deposition of two-layer coatings, including the mode of gas-abrasive treatment of the surface of implants made of titanium alloy before spraying. The synthesized HA powder and the Ti/HA coatings were investigated by optical microscopy and scanning electron microscopy with the energy dispersion analysis and the X-ray diffraction analysis.

Porous bioceramics produced by inkjet 3D printing: Effect of printing ink formulation on the ceramic macro and micro porous architectures control

Hierarchical structures with tailored macro/micro-porosity architecture play an important role in bone tissue regeneration. In 3D printing process, the printing ink formulation will influence on the ceramic macro and micro porous architectures. In this paper, HA powders of nano-sized grains (NP) with diameters of 30–50 nm, air jet milling powders (AP) with diameters of 10–30 μm, and spherical powder (SP) with diameters of 10–50 μm, were used as the initial printing materials in the printing ink formulations. The viscosity and the rheological behavior of printing inks were studied. The microstructure and morphology of the printed scaffold were observed and the mechanical properties of different types of scaffolds were tested. The results showed that the initial printing materials would influence on printing performance, both of the AP and SP inks may print porous scaffolds successfully. However, NP printing inks exhibited dramatic shrinkage and it is not suitable for 3D printing of bioceramics. The printing ink formulation also have effects on the ceramic macro and micro porous architectures and mechanical properties. The maximum compressive strength of SPS were 5.5 MPa, 3.2 MPa and 0.9 MPa with porosities of 60%, 70% and 80%, respectively. As the macroporosity decreases, the mechanical properties of the material would drop dramatically. With the same porosities, the compressive strength of APS were slightly higher than that of the SPS specimens.

Improvement in mechanical properties of nano-structured HA/TiO2 multilayer coatings deposited by high velocity suspension flame spraying (HVSFS)

In order to improve mechanical properties of HA coatings, nano-structured HA/TiO2 multilayer coatings composed of TiO2 bond layer, HA/TiO2 intermediate layer with different TiO2 contents and HA top layer were prepared by a high velocity suspension flame spraying (HVSFS) method using nano-sized HA and TiO2 powders. Phase constitution, compositions and microstructures were characterized by XRD, XPS, FTIR and SEM. Mechanical properties of multilayer coatings were investigated in comparison with the pure HA coating. Results show that multilayer coatings were mainly composed of HA and TiO2 phases, and presented well-bonded coating/substrate interfaces and porous surfaces as well as graded chemical compositions in coating thickness. Microhardness and Young's modulus of HA/TiO2 intermediate layers were increased with the TiO2 contents due to its reinforcement, and HA/TiO2 multilayer coatings revealed gradual mechanical properties from the TiO2 bond layer to HA top layer. Tensile strengths of HA/TiO2 double-layer coatings were improved due to TiO2 reinforcement in comparison with the pure HA coating. Wear properties of HA/TiO2 multilayer coatings were tested by a pin-on-disc method and were improved due to the presence of intermediate layers resulting in lower wear rates than that of the pure HA coating.

3D printing of hydroxyapatite scaffolds with good mechanical and biocompatible properties by digital light processing

Hydroxyapatite is a scaffold material widely used in clinical repair of bone defects, but it is difficult for traditional methods to make customized artificial bone implants with complicated shapes. 3D printing biomaterials used as personalized tissue substitutes have the ability to promote and enhance regeneration in areas of defected tissue. The present study aimed at demonstrating the capacity of one 3D printing technique, digital light processing (DLP), to produce HA scaffold. Using HA powder and photopolymer as raw materials, a mixture of HA mass ratio of 30 wt% was prepared by viscosity test. It was used for forming ceramic sample by DLP technology. According to differential scanning calorimetry and thermal gravity analysis, it was revealed that the main temperature range for the decomposition of photopolymer was from 300 to 500 °C. Thus, the two-step sintering process parameters were determined, including sintering temperature range and heating rate. XRD analysis showed that the phase of HA did not change after sintering. SEM results showed that the grain of the sintered ceramic was compact. The compression model was designed by finite element analysis. The mechanical test results showed that the sample had good compression performance. The biological properties of the scaffold were determined by cell culture in vitro. According to the proliferation of cells, it was concluded that the HA scaffold was biocompatible and suitable for cell growth and proliferation. The experimental results show that the DLP technology can be used to form the ceramic scaffold, and the photopolymer in the as-printed sample can be removed by proper high-temperature sintering. The ceramic parts with good compression performance and biocompatibility could be obtained.

Hydroxyapatite deposition on the laser modified Ti13Nb13Zr alloy

Abstract The Ti13Nb13Zr alloy was subjected to laser modification with the Nd:YAG laser provided that such treatment would increase the surface roughness followed improved adhesion of hydroxyapatite (HAp) coatings The hydroxyapatite was deposited by electrophoretic method in suspension of 0.5 g HA powder and 100 ml ethyl alcohol. The deposition was carried out for 10 min at 10 V voltage followed by drying at room temperature for 24 h and heating at 800°C for 1 h in vacuum. The thickness of the HAp coatings was found as of about 4.06 μm to 9.05 μm. The examinations of surfaces were carried out at each stage of the experiment with the ultra-high resolution scanning electron microscope. The measurements of surface roughness after laser treatment and after HAp deposition were performed with the Hommel Etamic Waveline profilograph.

The tension-shear fracture behavior of polymeric bone cement modified with hydroxyapatite nano-particles

Polymethylmethacrylate (PMMA)-based bone cement is a well-known polymer in the medicine, especially orthopedic. However it has some drawbacks like lack of enough biocompatibility and poor mechanical properties. These problems can be addressed by incorporation of nano-materials. Hydroxyapatite has been proved to enhance biocompatibility of acrylic bone cements. This bioceramic can affect the mechanical properties of polymeric cements as well. In this study, a number of fracture tests were carried out to investigate the influence of nano-hydroxyapatite (HA) on the fracture behavior of acrylic bone cement under combined tension-shear (mixed mode) loading conditions. Semi-circular specimens were prepared by incorporating different amounts of HA powder into the cement matrix. It was found that adding up to 10wt% HA into the cement causes an increase in the fracture toughness of PMMA/HA nano-composite in all modes. However, pure cement exhibited the greatest fracture resistance among all samples. Moreover, the comparison between the experimental and theoretical results showed that the generalized maximum tangential stress criterion could estimate the experimental data satisfactorily.

<i>In Vivo</i> Clinical Trial of Porous Starch-Hydroxyapatite Composite Biomaterials for Bone Regeneration

Biodegradable scaffold is an accepted and commercialized medical alternative choice for bone regeneration. In this project, we used our new invention, porous starch-Hydroxyapatite (HA) composite for in vivo clinical trial. The products were prepared from medical grade Thai rice starch mixed with high purity (>97%) HA powder from fresh cow bone, and already passed in vivo animal biocompatibility test, then processed by freeze-drying. There were 44 volunteers from orthopedic and neurosurgical division, 4 and 40 patients, respectively. The results were assessed by operative surgeons and nurses, pre-and intraoperative period, including size appropriateness, comfort handle, ease of cutting, void space filling, water stability, product weight, shelf storage, package opening, contamination risk and waste removal. All average satisfactory scales were more than 95% rating. For postoperative period, at least 6 months, the soft tissue swellings around surgical areas were resoluted about 3 days as usual healing process. There were no any symptoms or signs of infection or allergic reactions. The follow up of x-ray imaging showed well ossification about 2 months. All patients have gained good functional performance. So porous starch-HA composites biomaterial can be used for human bone and skull regeneration with completely safety and efficacy.

An ANFIS model to prediction of corrosion resistance of coated implant materials

In the present study, an adaptive neuro-fuzzy inference system (ANFIS) model has been used for predicting the corrosion resistance of AA6061-T4 alloy coated with micro-/nano-hydroxyapatite (HA) powders by sol–gel technique. The input parameters of the model consist of the HA powder size (micro-/nanoscale, 35 μm/20 nm), coating thickness (30, 60 and 85 μm) and potential values, while the output parameter is corrosion current density. The performance of proposed ANFIS model was tested on the potentiodynamic polarization scanning (PDS) curves by comparing experimental and the theoretical results of the coatings. The results showed that the generated PDS curves of the coatings are in definitely acceptable levels with obtained results in our experimental reference study. Then, the combined effect of arbitrary selected coating thickness and HA powder size on corrosion behaviour of the coatings was also predicted by trained ANFIS model without using any experimental data. And finally, the predicted results for the arbitrary selected coating thicknesses were compared by validation tests. The results showed that the ANFIS has potential to be used in industrial applications of biomedical implant materials coated with HA without performing any experiments after detailed systematic studies in the near future.

Microstructure, stability and biocompatibility of hydroxyapatite – titania nanocomposites formed by two step sintering process

In the present work, we report the characterization of TiO2-hydroxyapatite (HA) nanocomposites obtained by a two-step sintering (TSS) process of a mixture of HA and titanium hydride (TiH2) powders. The reactions underwent by TiH2 in the presence of HA and hydrogen release, and subsequently, titanium oxidation was examined by thermal analysis. A longer holding time in the second sintering stage enabled obtaining a homogenous TiO2-HA (36% rutile) composite with a thermal expansion coefficient of 11.46·10−6C−1 in the 40–1000°C range. Unconventional TSS process hinders HA decomposition to detrimental tricalcium phosphate (TCP). Wear rate of ceramics was determined by tribological measurements and the material biocompatibility was evaluated using MTT assay. Overall, cell viability results correlated with morphological observations indicated a good biocompatibility of HA-based composites at all tested concentrations. Incorporation of the TiO2 phase in HA by TSS process was found to be an efficient way to prepare bioceramics with improved performances.

Mechanosynthesis of hydroxyapatite–ferrite composite nanopowder

In the present work, an investigation of the mechanosynthesis of calcium hydroxyapatite (HA, Ca10(PO4)6(OH)2) from a mixture of calcium oxide (СаО) and ammonium hydrophosphate ((NH4)2HPO4) and mechanotreatment of HA in a planetary mill with the use of steel drums and milling body has been performed. The obtained results have shown that the mechanosynthesis of crystalline nanodisperse HA proceeds through the stage of formation of an amorphous material. The temperature treatment of HA powders at 1000°C has enabled us to establish the influence of the treatment time on the phase composition of the powders and establish the following sequence of phase transformations: Ca10(PO4)6(OH)2→β-Ca3(PO4)2 (tmilling~2h), β-Ca3(PO4)2→α-Ca3(PO4)2 (tmilling~5h), β-,α-Ca3(PO4)2→Ca10(PO4)6(OH)2 (tmilling~7h).The mechanosynthesis and mechanotreatment of hydroxyapatite in steel drums with steel balls is accompanied by the contamination of hydroxyapatite by their wear debris (iron + manganese). A large part of oxidized iron forms superparamagnetic inclusions distributed in HA powder. A small part of Fe3+ and Mn2+ ions from the steel wear debris enters into the hydroxyapatite lattice, substituting Ca2+ ions. As a result, a nanocomposite powder consisting of hydroxyapatite, alloyed by Fe3+ and Mn2+ ions and ferrite inclusions forms. The phase composition of HA powders, the degree of their alloying by Fe3+ and Mn2+ ions, and the content of ferrite inclusions can be controlled by changing the time of mechanotreatment.

Synthesis of Ag-Hydroxyapatite

Silver-bioceramics have a great potential to optimize the bone grafts materials to avoid microorganism infections on patients. The present study synthesized and characterized hydroxyapatite doped with silver (Ag), by an acidic route of precipitation method, and the proposal of the Ag-HA synthesis is to promote the bioactivity and bactericidal ability with less toxicity for organism. The samples were analyzed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy analysis. There was a pronounced grain growth after 1100°C HA and AgHA heat treatments for both HA and Ag-HA powders, observed by FEG-SEM analysis. XRD patterns of AgHA sintered at 1100°C showed HA as the main phase, but also a secondary whitlockite phase. However, 100% HA was observed for the Ag-HA samples heat treated at 700°C and 900°C. However, pure HA showed decomposition at 900°C. The acidic route of precipitation method showed to be effective for silver-doped hydroxyapatite production.

Synthesis and characterization of Cerium-doped hydroxyapatite/polylactic acid composite coatings on metal substrates

Ce-doped hydroxyapatite/polylactic acid (HA/PLA) composites serving as implant coatings have rarely been studied by other researchers in recent years. This paper was focused to study the existence of Ce ions in structure, chemical composition and surface morphology of HA and its composite coatings. Ce-doped HA powders were synthesized by chemical precipitation method with different Ce molar fractions (0(pure HA), 0.5 mol%, 1 mol% and 2 mol%). And Ce-doped HA/PLA composite coatings were fabricated for the first time on stainless steel substrates by spin coating technique. The obtained samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) coupled with energy dispersive X-ray detector (EDX), thermo gravimetric-differential thermal analysis (TG-DTA) and X-ray photoelectron spectroscopy (XPS). The results showed that Ce ions were doped into the crystal lattice of apatite successfully. The (Ce + Ca)/P atomic ratios in the doped HA/PLA samples ranged from 1.614 to 1.673, which were very close to the theoretical value of 1.67 for the stoichiometric HA. The addition of PLA could keep metal substrates from catalyzing the decomposition of HA. TG-DTA analysis indicated that Ce-doped HA powder had high thermal stability, and the SEM micrographs revealed that the surface topography of Ce-doped HA/PLA composite coatings was uniform and dense when the Ce molar fraction was 2 mol%. XPS results indicated that the Ce ions doped in HA showed mixed valences of Ce3+ and Ce4+.

Fabrication, characterization and cellular biocompatibility of porous biphasic calcium phosphate bioceramic scaffolds with different pore sizes

Facile wet-chemical methods are applied to synthesize hydroxyapatite and β-tricalcium phosphate nanoparticles, respectively. Porous biphasic calcium phosphate (BCP) bioceramic scaffolds are then fabricated using as-prepared HA and β-tricalcium phosphate nanoparticle powders. The macro pore diameter of BCP bioceramic scaffolds can be controlled by adjusting the amount of surfactants. The average diameter of the macro pores in BCP bioceramic scaffolds increases from 100 to 600µm with the decrease amount of sodium dodecyl sulfate from 0.8 to 0.5g, respectively. The BCP bioceramic scaffolds gradually degrade and the calcium-phosphate compounds fully deposit when soaking in simulated body fluid solution. Moreover, The BCP bioceramic scaffolds have outstanding biocompatibility to promote the cellular growth and proliferation of human dental pulp stem cells (hDPSCs). The hDPSCs also demonstrate favorable cellular adhering capacity on the pore surface of scaffolds, especially on the scaffolds with 100–200µm pore diameter. The porous BCP bioceramic scaffold with inter-connected pore structure, outstanding in vitro cellular biocompatibility, favorable cell viability and adhesion ability will be a promising biomaterial for bone or dentin tissue regeneration.

Effect of nano-hydroxyapatite reinforcement in mechanically alloyed NiTi composites for biomedical implant

Equi-atomic NiTi alloy composites reinforced with 0, 2, 4 and 6vol.% nano-hydroxyapatite (HA) were successfully synthesized using pressureless sintering. Pure Ni and Ti elements were ball milled for 10h in order to produce a mechanically alloyed equi-atomic NiTi alloy (MA-NiTi). Mechanically alloyed NiTi and HA powders were blended, compacted and then sintered for 3h at 1325K. The sintered density varied inversely with volume percent of HA reinforcement. The X-Ray diffraction spectra and SEM images showed the formation of multiple phases like NiTi, NiTi2, Ni3Ti, and Ni4Ti3. The back scattered-SEM image analysis confirmed the presence of Ni-rich and Ti-rich phases with increasing HA content. The 6vol.% HA reinforced composite showed Ni3Ti as the major phase having the highest hardness value which can be attributed to the presence of relatively harder phases along with higher HA content as a reinforcement. The composite of MA-NiTi with 2vol.% HA manifested the most desirable results in the form of better sintering density mainly due to the minute decomposition of NiTi into other phases. Therefore, the 2vol.% reinforced MA-NiTi composite can be exploited as a novel material for manufacturing biomedical implants.

Properties of calcium phosphates ceramic composites derived from natural materials

In this study, ceramics containing mixed phases of hydroxyapatite/beta-tricalcium phosphate (HA/β-TCP) were fabricated by a solid-state reaction technique. The HA powder was synthesized from cockle shells while the β-TCP powder was synthesized from egg shells. Pure HA and β-TCP fine powders were successfully obtained. The HA and β-TCP were mixed and subjected to a thermal treatment up to 1100°C. To form the mixed phase ceramics, the resulting powders were sintered at 1350°C. Effects of HA concentration on the properties of the studied ceramic were investigated. X-ray diffraction analysis revealed that all samples presented multiphase of calcium phosphate compounds. Average grain size of the ceramics decreased with the HA additive content. The 75wt% HA ceramic showed the maximum hardness value (5.5GPa) which is high when compared with many calcium phosphate ceramics. In vitro bioactivity test indicated that apatite forming increased with the HA additive content. To increase antibacterial activity, selected ceramics were coated with AgNO3. Antibacterial test suggested that an Ag compound coating on the ceramics could improve the antibacterial ability of the studied ceramics. In addition, the antibacterial ability for the Ag coated ceramics depended on the porosity of the ceramics.

Synthesis of hydroxyapatite from eggshell powders through ball milling and heat treatment

Every day, several million tons of eggshells are being generated as bio-waste across the world. This study demonstrates the synthesis of HA powder using dicalcium phosphate dehydrate (CaHPO4·2H2O, DCPD) and eggshell powders via ball milling and subsequent heat treatment. The formation of HA phase can be initiated by sintering the 1 h milled sample at 1000 °C for 1 h, while pure HA phase can be obtained upon sintering the 10 h milled sample. Additionally, the final products composed of biphasic calcium phosphate (HA + β-TCP crystals) can easily be prepared by ball milling for 5 h followed by heat treatment at 1000 °C for 1 h. The carbonate peaks observed in the FTIR analysis of the as-prepared HA closely matched those of A- and B-type carbonates, which is typical of the biological apatite. The elemental composition of the as-synthesized HA showed the presence of Ca, P, Mg, and Sr.

Study of the bioactivity, wettability and hardness behaviour of the bovine hydroxyapatite-diopside bio-nanocomposite coating

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.