Characterization of Magnesium‐Doped Hydroxyapatite Prepared by Sol‐Gel Process

Pure and doped hydroxyapatite (HA) nanocrystalline powders (Ca_10‐xMg_x(PO₄)₆OH₂) were synthesized using sol‐gel process. For this, calcium nitrate tetrahydrate, magnesium nitrate hexahydrate, and phosphorous pentoxide were used as precursors for Ca, Mg, and P, respectively. Calculated amounts of magnesium ions (Mg⁺²) especially from 0 to 10% (molar ratio) were incorporated as dopant into the calcium sol solution. The structure and morphology of the gels obtained after mixing the phosphorous and (calcium + magnesium) sol solution were different, and their condensations in time depend on the quantities of magnesium added. The several powders resulting from the gels dried and sintered at 500°C for 1 h were characterized by thermogravimetry (TG), Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), and inductively coupled plasma (ICP). Additionally, their agglomeration, morphology, and particle size were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The specific surface area of each sample was measured by the Brunauer–Emmett–Teller (BET) gas adsorption technique. The results of XRD, FTIR, and ICP values ranged between 0.45 and 2.11 mg/L indicated that the magnesium added in the calcium solution was incorporated in the lattice structure of HA so prepared, while those obtained by SEM and TEM confirmed the influence of Mg on their morphology (needle and irregular shape) and crystallite size, which is about 30–60 nm. The as‐prepared powders had a specific surface area ranged between 6.37 and 27.60 m²/g.     

Porous hydroxyapatite‐bioactive glass hybrid scaffolds fabricated via ceramic honeycomb extrusion

The successful fabrication of hydroxyapatite‐bioactive glass scaffolds using honeycomb extrusion is presented herein. Hydroxyapatite was combined with either 10 wt% stoichiometric Bioglass^® (BG1), calcium‐excess Bioglass^® (BG2) or canasite (CAN). For all composite materials, glass‐induced partial phase transformation of the HA into the mechanically weaker β‐tricalcium phosphate (TCP) occurred but XRD data demonstrated that BG2 exhibited a lower volume fraction of TCP than BG1. Consequently, the maximum compressive strength observed for BG1 and BG2 were 30.3 ± 3.9 and 56.7 ± 6.9 MPa, respectively, for specimens sintered at 1300°C. CAN scaffolds, in contrast, collapsed when handled when sintered below 1300°C, and thus failed. The microstructure illustrated a morphology similar to that of BG1 sintered at 1200°C, and hence a comparable compressive strength (11.4 ± 3.1 MPa). The results highlight the great potential offered by honeycomb extrusion for fabricating high‐strength porous scaffolds. The compressive strengths exceed that of commercial scaffolds, and biological tests revealed an increase in cell viability over 7 days for all hybrid scaffolds. Thus it is expected that the incorporation of 10 wt% bioactive glass will provide the added advantage of enhanced bioactivity in concert with improved mechanical stability.     

Improvement of the hydroxyapatite mechanical properties by direct microwave sintering in single mode cavity

The main purpose of this study consists in investigating the direct microwave sintering of hydroxyapatite (HA) in a single mode cavity. Firstly, stoichiometric HA powders were synthesized by a coprecipitation method from diammonium phosphate and calcium nitrate solutions and shaped by slip-casting. Then, using the one-step microwave process, dense pellets with fine microstructures were successfully obtained in short sintering timespan. A parametric study permitted to determine the influence of powder grain size, sintering temperature and dwell time on the sintered samples microstructures. The Young's modulus (E) and hardness (H) were measured by nanoindentation and the values discussed according to the microstructure. Finally, the resulting mechanical properties determined on the microwave sintered samples (E = 148.5 GPa, H = 9.6 GPa, σ_compression = 531.3 MPa and K_IC = 1.12 MPa m^1/2) are significantly higher than those usually reported in the literature, whatever the sintering process, and could allow the use of HA for structural applications.     

Sinterability of Forsterite Prepared via Solid‐State Reaction

In this work, the sinterability of forsterite powder synthesized via solid‐state reaction was investigated. X‐ray diffraction (XRD) analyses indicate that the synthesized powder possessed peaks that correspond to stoichiometric forsterite. Scanning electron micrographs revealed that the powders were formed agglomerates, which were made up of loosely packed fine particles. Subsequently, the forsterite powders were cold isostatically pressed into a disk shape under 200 MPa and sintered in air at temperature ranging from 1200°C to 1500°C (interval of 50°C) with ramp rate of 10°C/min and dwelling time of 2 h. The sinterability of each sintered samples was examined in terms of phase stability, relative density, Vickers hardness, fracture toughness, and microstructural examination. XRD examination on all the sintered samples exhibited pure forsterite, in which the generated peaks were found to be in a good agreement with JCPDS card no. 34‐0189. The densification of forsterite progressed to reach a maximum relative density of ~91% at 1500°C. This study also revealed that high‐strength forsterite ceramic can be synthesized via solid‐state reaction as forsterite attained favorable mechanical properties, having fracture toughness of 4.88 MPam^1/2 and hardness of 7.11 GPa at 1400°C.     

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 75 wt% HA ceramic showed the maximum hardness value (5.5 GPa) 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.     

Influence of precursor deficiency sites for borate incorporation on the structural and biological properties of boronated hydroxyapatite

The biological properties of hydroxyapatite (HA) are significantly influenced by its compositional characteristics especially doping elements and/or Ca/P ratio, which can be altered by precursor chemistry. In this study, a group of boronated (B-incorporated) hydroxyapatite (BHA) was synthesized using a precipitation method by setting the Ca/P ratio to the stoichiometric value of HA (1.67), while altering the precursor chemistry by adjusting either (Ca + B)/P (Ca-deficient precursor, BC) or Ca/(P + B) (P-deficient precursor, BP). After heat-treatment, the partial decomposition of the BC was observed, forming tricalcium phosphate as the byproduct, however, the BP showed phase stability at all temperatures. The B-ionic species in the form of (BO₂)^? and (BO₃)^3? were incorporated into the HA structure at the (PO₄)^3? and (OH)^? positions, respectively. The incorporation of the B species also facilitated the incorporation of (CO₃)^2? groups specifically in the BPs. This is the first finding on BHA reporting that preferential (CO₃)^2? incorporation depends on the precursor chemistry used. As a result, osteoblast adhesion was superior on the BPs compared to pure HA owing to the carbonated structure, increasing cell spreading area. As such, this in vitro study highlighted that the present P-deficient precursor approach for synthesizing BHA improved biocompatibility properties and should, thus, be further considered for the next-generation of improved orthopedic applications.     

Solid‐State NMR Study of Mn2+ for Ca2+ Substitution in Thermally Processed Hydroxyapatites

In the present study calcium hydroxyapatites enriched at 0.08 wt% in Mn²⁺ ions (Mn–HA) and their unsubstituted forms (HA) were synthesized using the same standard wet chemical route. Mn‐HA and HA were both calcined at 800°C to give Mn‐HAc and HAc, respectively or sintered at 1250°C, to give Mn‐HAs and HAs, respectively. The influence of the heat treatment on physicochemical properties of Mn‐HA was investigated using powder X‐ray diffraction (PXRD), scanning, and transmission electron microscopy (SEM and TEM), and solid‐state nuclear magnetic resonance (ssNMR). Mn‐HAc and Mn‐HAs were compared to each other and to HAc and HAs, respectively. Assignment of the proton ssNMR peaks from high‐temperature‐treated apatites has been revised. It was found that Mn–HAc and HAc were nanocrystalline, while Mn‐HAs and HAs comprised micrometer sized, partially fused particles (SEM and TEM). PXRD and ssNMR demonstrated that the incorporation of Mn²⁺ into the crystal lattice of hydroxyapatite significantly facilitates its dehydroxylation and decomposition to oxyhydroxyapatite during calcination at 800°C, and induces its transformation to tetracalcium phosphate (TTCP) and alpha‐tricalcium phosphate (α‐TCP) at 1250°C. Contamination by CaO has also been detected. The ¹H→³¹P NMR cross‐polarization experiments have indicated that the Mn²⁺ ions preferentially occupied the Ca(I) position in the crystallographic unit cell of Mn‐HAc. In Mn‐HAs, the Mn²⁺ ions were evenly distributed between the Ca(I) and Ca(II) positions.     

Synthesis and Optimization of the Production of Millimeter‐Sized Hydroxyapatite Single Crystals by Cl−–OH− Ion Exchange

Millimeter‐sized hydroxyapatite (HA) single crystals were synthesized from chlorapatite (ClAp) crystals via the ionic exchange of Cl^? for OH^? at high temperature. X‐ray diffraction, Fourier‐transform infrared spectroscopy, and chloride content measurements were used to follow the progress of this conversion, and to assess the effect of the experimental conditions (temperature, time, and atmosphere). Cl^?→OH^? exchange took place homogeneously and was enhanced by firing in wet air. After firing at 1425°C for 2 h 92% of the Cl^? ions were exchanged by OH^? while maintaining crystal integrity. Temperatures above 1450°C damaged the surface of the crystals, destroying the hexagonal habit at 1500°C. The composition of these apatite crystals was close to bone mineral content. Their nanoindentation hardness (8.7 ± 1.0 GPa) and elastic nanoindentation modulus (120 ± 10 GPa) were similar to those of the starting ClAp (6.6 ± 1.5 GPa, and 110 ± 15 GPa, respectively). However, their average flexural strength was ~25% lower due to the formation of defects during the thermal treatments.     

Liquid‐phase sintering,microstructural evolution,and microwave dielectric properties of Li2Mg3SnO6–LiF ceramics

The liquid‐phase sintering behavior and microstructural evolution of x wt% LiF aided Li₂Mg₃SnO₆ ceramics (x = 1‐7) were investigated for the purpose to prepare dense phase‐pure ceramic samples. The grain and pore morphology, density variation, and phase structures were especially correlated with the subsequent microwave dielectric properties. The experimental results demonstrate a typical liquid‐phase sintering in LiF–Li₂Mg₃SnO₆ ceramics, in which LiF proves to be an effective sintering aid for the Li₂Mg₃SnO₆ ceramic and obviously reduces its optimum sintering temperature from ~1200°C to ~850°C. The actual sample density and microstructure (grain and pores) strongly depended on both the amount of LiF additive and the sintering temperature. Higher sintering temperature tended to cause the formation of closed pores in Li₂Mg₃SnO₆‐x wt% LiF ceramics owing to the increase in the migration ability of grain boundary. An obvious transition of fracture modes from transgranular to intergranular ones was observed approximately at x = 4. A single‐phase dense Li₂Mg₃SnO₆ ceramic could be obtained in the temperature range of 875°C‐1100°C, beyond which the secondary phase Li₄MgSn₂O₇ (<850°C) and Mg₂SnO₄ (>1100°C) appeared. Excellent microwave dielectric properties of Q × f = 230 000‐330 000 GHz, ε_r = ~10.5 and τ_f = ~?40 ppm/°C were obtained for Li₂Mg₃SnO₆ ceramics with x = 2‐5 as sintered at ~1150°C. For LTCC applications, a desirable Q × f value of ~133 000 GHz could be achieved in samples with x = 3‐4 as sintered at 875°C.     

Preparation and characterization of single phase,biphasic and triphasic calcium phosphate whisker-like fibers by homogenous precipitation using urea

Whisker-like calcium phosphate fibers were prepared by a homogenous precipitation method under refluxing conditions in solutions with a Ca/P molar ratio of 1.67 at 90 °C and pH 3.0 using urea as additive. The precipitates were characterized by XRD, FTIR, SEM, and FE-SEM. The ICP spectroscopy and elemental analyzer were used to determine Ca/P ratio and carbonate content of products, respectively. The results indicate that the morphology and structural characteristics of the precipitates depend on the urea concentration and reaction time. Whisker-like biphasic monetite/hydroxyapatite (HA) fibers with a mean length of 60 µm and a mean width of 1.0 µm were obtained with the use of a low concentration of urea. Calcination of the biphasic calcium phosphate at 800 °C led to the formation of a triphasic mixture of HA/whitlockite (β-TCP)/calcium pyrophosphate (CPP) with a whisker-like morphology. The use of a higher concentration of urea was caused to form a mixed morphology of spherulites/whisker-like fibers consisting of octacalcium phosphate (OCP) and HA phases. When the reaction time was increased to 10 days, both the above biphasic calcium phosphates transformed to a single phase HA which its morphology and growth pattern were similar to those of a whisker, according to FE-SEM images. The HA whiskers produced by a lower amount of urea had a lower carbonate content compared to those obtained using a higher urea concentration.     

Low‐Temperature Sintering of β‐Spodumene Ceramics Using Li2O–GeO2 as a Sintering Additive

Low‐temperature sintering of β‐spodumene ceramics with low coefficient of thermal expansion (CTE) was attained using Li₂O–GeO₂ sintering additive. Single‐phase β‐spodumene ceramics could be synthesized by heat treatment at 1000°C using highly pure and fine amorphous silica, α‐alumina, and lithium carbonate powders mixture via the solid‐state reaction route. The mixture was calcined at 950°C, finely pulverized, compacted, and finally sintered with or without the sintering additive at 800°C–1400°C for 2 h. The relative density reached 98% for the sample sintered with 3 mass% Li₂O–GeO₂ additive at 1000°C. Its Young's modulus was 167 GPa and flexural strength was 115 MPa. Its CTE (from R.T. to 800°C) was 0.7 × 10^?6 K^?1 and dielectric constant was 6.8 with loss tangent of 0.9% at 5 MHz. These properties were excellent or comparative compared with those previously reported for the samples sintered at around 1300°C–1400°C via melt‐quenching routes. As a result, β‐spodumene ceramics with single phase and sufficient properties were obtained at about 300°C lower sintering temperature by adding Li₂O–GeO₂ sintering additive via the conventional solid‐state reaction route. These results suggest that β‐spodumene ceramics sintered with Li₂O–GeO₂ sintering additive has a potential use as LTCC for multichip modules.     

Temperature stable K0.5(Nd1−xBix)0.5MoO4 microwave dielectrics ceramics with ultra‐low sintering temperature

K_0.5(Nd_1?xBi_x)_0.5MoO₄ (0.2 ≤ x ≤ 0.7) ceramics were prepared via the solid‐state reaction method. All ceramics densified below 720°C with a uniform microstructure. As x increased from 0.2 to 0.7, relative permittivity (?_r) increased from 13.6 to 26.2 commensurate with an increase in temperature coefficient of resonant frequency (TCF) from – 31 ppm/°C to + 60 ppm/°C and a decrease in Qf value (Q = quality factor; f = resonant frequency) from 23 400 to 8620 GHz. Optimum TCF was obtained for x = 0.3 (?15 ppm/°C) and 0.4 (+4 ppm/°C) sintered at 660 and 620°C with ?_r ~15.4, Q_f ~19 650 GHz, and ?_r ~17.3, Q_f ~13 050 GHz, respectively. Ceramics in this novel solid solution are a candidate for ultra low temperature co‐fired ceramic (ULTCC) technology.     

The Effect of Particle Size on the Mechanical and Microstructural Properties of Freeze‐Casted Macroporous Hydroxyapatite Scaffolds

Two different hydroxyapatites with the particle sizes of 3.9 and 1.69 μm were chosen. Slurries with initial hydroxyapatite concentration of 15 vol% were prepared. Different cooling rates from 2 to 14°C/min were utilized. The specimens were sintered at different temperatures of 1250–1350°C. The phase composition (by X‐Ray Diffraction), microstructure (by Scanning Electron Microscopy), mechanical characteristics, and the porosity of sintered samples were assessed. The porosity of the sintered samples was in range of ~57–83%, and the compressive strength varied from ~1.7 to 15 MPa. The mechanical strength of the scaffolds increased as a function of cooling rate and sintering temperature.     

Nurse′s A‐Phase: Synthesis and Characterization in the Binary System Ca2SiO4–Ca3(PO4)2

In the present study, a new single phase Si–Ca–P‐based ceramic was obtained by conventional sintering of compacted mixtures of calcium hydrogen phosphate anhydrous, calcium carbonate, and silicon oxide. The synthesis conditions were the followings: heated up to 1550°C for a total period of time of 72 h (3 d), with quenching in liquid nitrogen, milling, pressing, and reheating every 24 h. Second, heating at 1300°C/3 h and subsequent annealed at 1200°C/24 h. Mineralogical and microstructural characterization of the obtained Si–Ca–P‐based material was determined by Differential Thermal Analysis, X‐ray diffraction, Scanning Electron Microscopy with attached wavelength dispersive spectroscopy, Micro‐Raman and Fourier Transform Infrared Spectrometer. The results showed a single Si–Ca–P phase material with a Ca₂SiO₄/Ca₃(PO₄)₂ molar ratio equal to 2:1. The parameters of the Weibull distribution of strength, determined by diametrical compression of disks, were: modulus, m = 13, and characteristic strength σ₀ = 0.60 MPa.     

Structure of the hydroxyapatite plasma-sprayed coatings deposited on pre-heated titanium substrates

Plasma spraying is the most commonly used thermal spray method for the application of hydroxyapatite (HA, Ca₁₀(PO₄)₆(OH)₂) coatings. In the present study, the HA coatings were plasma spraying deposited onto plates of titanium pre-heated to 20 °C, 300 °C and 550 °C. The obtained HA coatings were investigated by means of X-ray diffraction and scanning electron microscopy. It is found that the coatings, in addition to HA, contain the tetracalcium phosphate (TTCP, (Ca₄(PO₄)₂O) phase (~10%) and a small amount of CaO (<2%). Crystal structure of HA in the coatings is revealed to be distorted. The PO4 tetrahedrons are deformed (Baur distortion coefficient D1(TO) ~0.2). The distances Ca1-O1 and Ca1-O2 are changed as compared to these in stoichiometric hydroxyapatite. These distortions are considered as a result of internal stresses, which are demonstrated in the broadening of peaks on X-ray diffraction pattern of HA. Microstructure of coatings consisting of flattened splats was formed by fully molten particles. The axial base texture was developed in the coatings. Ultrastructure is columnar with a preferred orientation of c-axes of the crystals parallel to the normal of plane coating n. The heating of substrate has a marked effect on the ultrastructure of coatings: the domain size increases from 790 to 1100 Å, the strain Δ decreases from 1.6·10^-3 to 1,2·10^–3, TTCP content diminishes from 12% to 7%. These results show that the effects due to heating of the substrate may be associated with partial recovery of HA microstructure.     

Influence of A‐site nonstoichiometry on the electrical properties of BT‐BMT

A stoichiometric and 2 mol% Ba deficient samples in the formulation 0.5BaTiO₃‐0.5BiMg_1/2Ti_1/2O₃ (BT‐BMT) were processed via a mixed oxide solid‐state route. The deficient sample exhibited a high relative permittivity (2100±15%) over the temperature range 90‐450°C and a low dielectric loss (tanδ < 0.01), maintained up to high temperature (430°C). The samples exhibited intrinsic conduction mechanism and showed an n‐type character. By introducing 2 mol% Ba vacancies, a dramatic influence on the dielectric loss was observed which was mainly associated with the trapping of electrons by barium‐oxygen vacancy pair associated with the intentionally produced cation vacancies. Thus, control of composition by creating deficiency allows fine tuning of the dielectric properties of BT‐BMT ceramics for applications in high‐temperature multilayered ceramic capacitors.     

Alternative green preparation of mesoporous calcium hydroxyapatite by chemical reaction of eggshell and phosphoric acid

Eggshell is a rich source of CaCO₃ with a high purity content of more than 96.35% w/w and a potential raw material for calcium hydroxyapatite preparation. Mesoporous and nano-particulate calcium hydroxyapatite was prepared from duck eggshell from the chemical reaction with phosphoric acid followed by the calcinations at 800, 900, and 1000°C for 2 hours. The optimum condition to obtain the high purity calcium hydroxyapatite was by sintering calcium phosphate Ca₃(PO₄)₂ at 1000°C for 2 hours. The average particle size, pore diameter, specific surface, and true density of the sample sintered at 1000°C for 2 hours were 101.93 ± 12.15 nm, 98.96 Å, 2.12 m²/g, and 3.02 g/cm³, respectively, appearing as a soft fine powder with a white color. The raw duck eggshell is a potential candidate as a bio-ceramic material to prepare calcium hydroxyapatite suitable for use in various bio-applications such as bone tissue engineering, drug and gene delivery, remineralizing agent in toothpaste, and bone void fillers for orthopedic and restoration.     

Comparative analysis and antibacterial properties of thermally sintered apatites with varied processing conditions

Hydroxyapatite (HA) and biphasic hydroxyapatite/beta-tricalcium phosphate (biphasic HA/β-TCP) were synthesized using thermal sintering. The parameters- sintering temperature (600°C, 900°C, and 1200°C), biological source used (fish bone, egg shells, and fish scales), and soaking time (2, 6, and 10 hours) were permuted to study their effects on the properties of the resultant apatite. Morphological study revealed that the smallest (60 nm) spherical particle and the largest (470 nm) irregular shaped particle were obtained from the fish bone sample sintered at 600°C and at 1200°C respectively. FTIR and XRD results showed that as the sintering temperature is increased, the phase transformation from HA to β-TCP takes place. Only the final products from fishbone sample at 600°C are pure carbonated HA. The crystallinity of synthesized particles ranged from 79% to 98%. Soaking time has no effect on phase composition of the apatite but has significant effect on crystallite size; increase in soaking time increases crystallite size and particle shape becomes more spherical. Interestingly, the fish bone sample sintered at 900°C has higher crystallinity and crystallite size compared to the fish scale sample sintered at the same temperature. EDX confirmed that non-stoichiometric apatite with Ca/P ratio ranging from 1.47 to 1.91 can be obtained by varying the sintering conditions. The antibacterial test revealed that both calcium apatite obtained from fish bones and fish scales have inhibited bacterial growth; apatite from fish bone works faster than fish scales. The in vitro cytotoxicity test ensured that all the calcium apatite except for eggshell are non-cytotoxic. Thus, apatite with excellent microbial activity can be obtained by using fish wastes, and by tuning the sintering parameters, the apatite with desired types and properties can be synthesized for different biomedical applications.     

Low‐Temperature‐Fired ReVO4 (Re = La,Ce) Microwave Dielectric Ceramics

We report a series of ReVO₄ (Re = La, Ce) microwave dielectric ceramics fabricated by a standard solid‐state reaction method. X‐ray diffraction and scanning electron microscopy measurements were performed to explore the phase purity, sintering behavior, and microstructure. The analysis revealed that pure and dense monoclinic LaVO₄ ceramics with a monazite structure and tetragonal CeVO₄ ceramics with a zircon structure could be obtained in their respective sintering temperature range. Furthermore, LaVO₄ and CeVO₄ ceramics sintered at 850°C and 950°C for 4 h possessed out‐bound microwave dielectric properties: ε_r = 14.2, Q × f = 48197 GHz, τ_f = ?37.9 ppm/°C, and ε_r = 12.3, Q × f = 41 460 GHz, τ_f = ?34.4 ppm/°C, respectively. The overall results suggest that the ReVO₄ ceramics could be promising materials for low‐temperature‐cofired ceramic technology.     

Obtaining hydroxyapatite from the exoskeleton and spines of the purple sea urchin Strongylocentrotus purpuratus

We present a simple, quick, and viable way to produce hydroxyapatite (HA) from a waste by-product of the sea food industry, this was achieved by submitting the exoskeleton of the purple sea urchin Strongylocentrotus purpuratus through a chemical reaction with H₃PO₄ at 3 different times (3, 18, and 36 hours) with constant stirring at 35-40°C. The characterization of the materials was made by several techniques (FTIR, XRD, SEM-EDS, and TEM).The FTIR results confirmed the presence of the HA characteristic functional groups OH, PO₄, and CO₃, the XRD characterization showed that the synthesis of calcium phosphates such as brushite and HA was achieved by confirming the presence of its characteristic peaks, also the EDS analysis confirmed the expected HA Ca/P atomic ratio of 1.67. This work shows that we can take advantage from raw materials derived from processing sea food by giving it an added value for the biomedical industry.