Biological apatites contain several elements as traces. In this work, Magnesium and fluorine co-substituted hydroxyapatites with the general formula Ca9Mg(PO4)6(OH)2-yFy, where y = 0, 0.5, 1, 1.5 and 2 were synthesize...Biological apatites contain several elements as traces. In this work, Magnesium and fluorine co-substituted hydroxyapatites with the general formula Ca9Mg(PO4)6(OH)2-yFy, where y = 0, 0.5, 1, 1.5 and 2 were synthesized by the hydrothermal method. After calcination at 500℃, the samples were pressureless sintered between 950℃ and 1250℃. The substitution of F- for OH- had a strong influence on the densification behavior and mechanical properties of the materials. Below 1200℃, the density steeply decreased for y = 0.5 sample. XRD analysis revealed that compared to hydroxylfluorapatite containing no magnesium, the substituted hydroxyfluorapatites decomposed, and the nature of the decomposition products is tightly dependent on the fluorine content. The hardness, elastic modulus and fracture toughness of these materials were investigated by Vickers’s hardness testing. The highest values were 622 ± 4 GPa, 181 ± 1 GPa and 1.85 ± 0.06 MPa.m1/2, respectively.展开更多
Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)an...Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)and 3‐mercaptopropyl trimethoxysilane(MPS)to afford dual surface‐capped nano‐amendment HAPIDA/MPS.The structure of HAP‐IDA/MPS was characterized,and its adsorption performance for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)was evaluated.The total adsorption capacity of 0.10 g HAP‐IDA/MPS nano‐amendment for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)with an initial mass concentration of 20 mg·L^(-1) reached 13.7 mg·g^(-1),about 4.3 times as much as that of HAP.Notably,HAP‐IDA/MPS nano‐amendment displayed the highest immobilization rate for Hg^(2+),possibly because of its chemical reaction with-SH to form sulfide,possessing the lowest solubility product constant among a variety of metal sulfides.展开更多
Biodegradable magnesium(Mg)alloys have received increased attention as temporary medical implants due to their mechanical properties and density,similar to natural bone.However,the fast corrosion of Mg alloys in a phy...Biodegradable magnesium(Mg)alloys have received increased attention as temporary medical implants due to their mechanical properties and density,similar to natural bone.However,the fast corrosion of Mg alloys in a physiological condition limits their wide applications.Hence,hydroxyapatite(HAp)coatings on Mg alloys have attracted much attention to address this corrosion issue and enhance the surface functionalities.In this paper,we present a review of HAp coating strategies on Mg alloys,including the sol-gel method,hydrothermal treatment,biomimetic coating,electrochemical deposition,electrophoretic deposition,and plasma electrolytic oxidation technique,and their recent progress to enhance the surface characteristics of Mg alloys.This review focused on aspects of coating morphology,hybrid formulations,and how they influence corrosion behavior as well as in vitro and in vivo performance.Moreover,we have discussed the future prospects of HAp-coating strategies,emphasizing on multifunctional,hybrid,and smart coatings for next-generation implant materials.展开更多
BACKGROUND Bone regeneration is a central focus of regenerative medicine,with applications in orthopedics and dentistry,particularly for treating bone defects caused by trauma,infection,or congenital anomalies.Synthet...BACKGROUND Bone regeneration is a central focus of regenerative medicine,with applications in orthopedics and dentistry,particularly for treating bone defects caused by trauma,infection,or congenital anomalies.Synthetic biomaterials,often combined with fibrin derivatives,offer promising solutions for bone healing and restoration.AIM To Explore the increasingly important role of the association of synthetic biomaterials with fibrin in bone regeneration.METHODS Search terms included:“synthetic biomaterials AND fibrin sealant”,“hydroxyapatite AND fibrin sealant”,“tricalcium phosphate AND fibrin sealant”,and“synthetic biomaterials AND platelet-rich fibrin(PRF)”,resulting in 67 articles.After rigorous screening,21 articles met the inclusion criteria.RESULTS The reviewed studies assessed biomaterials like hydroxyapatite(HA),β-tricalcium phosphate(β-TCP),and fibrin-based products.Key findings highlighted the enhanced osteoconductivity and biocompatibility of HA andβ-TCP,especially when combined with fibrin sealants.These composites show significant potential for improving cellular adhesion,promoting osteogenic differentiation,and accelerating bone regeneration.The antimicrobial properties and structural support for cell growth of certain biomaterials indicate a promising potential for clinical applic-ations.CONCLUSION This systematic review emphasizes the growing role of fibrin-based biomaterials in bone regeneration and urges continued research to improve their clinical use for complex bone defects.展开更多
Bone defects caused by trauma,infection,or congenital anomalies remain a significant challenge in orthopedic and dental practice,necessitating innovative strategies to enhance healing and functional restoration.This s...Bone defects caused by trauma,infection,or congenital anomalies remain a significant challenge in orthopedic and dental practice,necessitating innovative strategies to enhance healing and functional restoration.This systematic review by Pagani et al synthesizes evidence on the synergistic role of synthetic biomaterials,such as hydroxyapatite(HA)andβ-tricalcium phosphate(β-TCP),combined with fibrin derivatives in bone regeneration.Analyzing 21 studies,the authors demonstrate that HA andβ-TCP composites exhibit superior osteoconductivity and biocompatibility when integrated with fibrin sealants or plateletrich fibrin,promoting cellular adhesion,osteogenic differentiation,and accelerated healing.While these studies underscore the potential of these biomaterialfibrin hybrids,limitations such as variability in fibrin preparation,lack of longterm data,and insufficient standardization hinder clinical translation.This editorial contextualizes these findings within the evolving landscape of regenerative medicine,emphasizing the need for optimized formulations,interdisciplinary collaboration,and robust clinical trials to bridge laboratory innovation to bedside application.展开更多
The field of bone tissue engineering has experienced an increase in prevalence due to the inherent challenge of the natural regeneration of significant bone deformities.This investigation focused on the preparation of...The field of bone tissue engineering has experienced an increase in prevalence due to the inherent challenge of the natural regeneration of significant bone deformities.This investigation focused on the preparation of Three-Dimensional(3D)-printed Polycaprolactone(PCL)scaffolds with varying proportions of Nanohydroxyapatite(NHA)and Nanoclay(NC),and their physiochemical and biological properties were assessed.The mechanical properties of PCL are satisfactory;however,its hydrophobic nature and long-term degradation hinder its use in scaffold fabrication.NHA and NC have been employed to improve the hydrophilic characteristics,mechanical strength,adhesive properties,biocompatibility,biodegradability,and osteoconductive behavior of PCL.The morphology results demonstrated 3D-printed structures with interconnected rectangular macropores and proper nanoparticle distribution.The sample containing 70 wt%NC showed the highest porosity(65.98±2.54%),leading to an increased degradation rate.The compressive strength ranged from 10.65±1.90 to 84.93±9.93 MPa,which is directly proportional to the compressive strength of cancellous bone(2–12 MPa).The wettability,water uptake,and biodegradability of PCL scaffolds considerably improved as the amount of NC increased.The results of the cellular assays exhibited increased proliferation,viability,and adhesion of MG-63 cells due to the addition of NHA and NC to the scaffolds.Finally,according to the in vitro results,it can be concluded that 3D-printed samples with higher amounts of NC can be regarded as a suitable scaffold for expediting the regeneration process of bone defects.展开更多
Hydroxyapatite (HA) is widely explored as a biocompatible filler to enhance the mechanical and functional properties of glass ionomer cements (GICs). HA of particle sizes 15 µm and 30 µm were added as a fill...Hydroxyapatite (HA) is widely explored as a biocompatible filler to enhance the mechanical and functional properties of glass ionomer cements (GICs). HA of particle sizes 15 µm and 30 µm were added as a filler into a matrix, composed of calcium aluminosilicate GICs and Poly-acrylic acid (PAA) in varying ratios. The tested ratios were Glass:PAA = 2:1 and Glass:HA:PAA = 2:0.5:1 to improve the mechanical strength of a conventional GIC. Mechanical properties, including compressive, flexural, and diametral tensile strength were studied at different setting times. The compressive strength (CS) was improved with hydroxyapatite addition and prolonged setting time while diametral tensile strength (DTS) did not follow any specific trend. The flexural strength (FS) of the composite cement was increased with increasing setting time regardless of the particle size of hydroxyapatite. The FTIR spectra of hydroxyapatite of particle sizes 15 μm and 30 μm are similar but for HA-GIC composites, the FTIR spectra, the peak around 1460 cm−1 are due to C-H and the peak at 1553 cm−1 is due to calcium carboxylate with calcium in a bridging mode which would be an excellent material that chemically bonds to the tooth structure, making it effective for both restorative procedures and cavity fillings. Scanning electron microscopy (SEM) microstructural study revealed that the glass particles were wrenched out, which was a cohesive fracture. The X-ray diffraction (XRD) pattern showed that the hydroxyapatite has a crystalline single-phase, hexagonal structure. The sharp peaks between the 2-theta range of 30 - 40 degrees are the same as in enamel powder. The spectra indicate the pure set cement as amorphous since there is no prominent peak, but with the addition of hydroxyapatite filler, the peak in the 2-theta range of 20 - 35 degrees is ascribed to crystalline apatite structure. The results indicate that incorporating hydroxyapatite into GIC significantly enhances its mechanical properties and structural integrity, suggesting its potential as an improved material for dental and restorative applications.展开更多
Tissue engineering holds promise in developing materials for biological applications,such as bone tissue repair.This study focuses on bioabsorbable and biocompatible polymers like Poly(L-lactic acid)(PLLA),Polyurethan...Tissue engineering holds promise in developing materials for biological applications,such as bone tissue repair.This study focuses on bioabsorbable and biocompatible polymers like Poly(L-lactic acid)(PLLA),Polyurethane(PU),and Polycaprolactone(PCL),along with nanohydroxyapatite(nHA),an essential osteoconductive ceramic.The main objective was the development and characterization of scaffolds obtained by Rotary Jet Spinning(RJS)using PLLA,PU,and PCL incorporated with nHA,for bone-related applications.The resulting scaffolds exhibited uniform fiber morphology and a rough surface,ideal for effective bone-tissue interaction.The crystallinity indicated the scaffolds’bioactivity by apatite deposition in simulated body fluid.In addition,in vitro biological assays using preosteoblastic cells showed the biocompatibility of cells based on cell viability and adhesion parameters on the scaffolds.The results underscore the capacity of scaffolds incorporating nHA to promote both cell proliferation and osteoconduction,which are key elements essential for achieving effective bone regeneration.展开更多
Hierarchical porous structure,which include macropores,minor pores,and micropores in scaffolds,are essential in the multiple biological functions of bone repair and regeneration.In this study,patientcustomized calcium...Hierarchical porous structure,which include macropores,minor pores,and micropores in scaffolds,are essential in the multiple biological functions of bone repair and regeneration.In this study,patientcustomized calcium-deficient hydroxyapatite(CDHA)scaffolds with three-level hierarchical porous structure were fabricated by indirect 3D printing technology and particulate leaching method.The sacrificial template scaffolds were fabricated using a photo-curing 3D printer,which provided a prerequisite for the integral structure and interconnected macropores of CDHA scaffolds.Additionally,20 wt%pore former was incorporated into the slurry to enhance the content of smaller pores within the CDHA-2 scaffolds,and then the CDHA-2 scaffolds were sintered to remove the sacrificial template scaffolds and pore former.The obtained CDHA-2 scaffolds exhibited interconnected macropores(300-400μm),minor pores(∼10-100μm),and micropores(<10μm)distributed throughout the scaffolds,which could promote bone tissue ingrowth,increase surface roughness,and enhance protein adsorption of scaffolds.In vitro studies identified that CDHA-2 scaffolds had nanocrystal grains,high specific surface area,and outstanding protein adsorption capacity,which could provide a microenvironment for cell adhesion,spreading,and proliferation.In addition,the murine intramuscular implantation experiment suggested that CDHA-2 scaffolds exhibited excellent osteoinductivity and were superior to traditional BCP ceramics under conditions without the addition of live cells and exogenous growth factors.The rabbit calvarial defect repair results indicated that CDHA-2 scaffolds could enhance in situ bone regeneration.In conclusion,these findings demonstrated that the hierarchical porous structure of CDHA scaffolds was a pivotal factor in modulating osteoinductivity and bone regeneration,and CDHA-2 scaffolds were potential candidates for bone regeneration.展开更多
Solid-state polymer electrolytes are crucial for advancing solid-state lithium-metal batteries owing to their flexibility,excellent manufacturability,and strong interfacial compatibility.However,their widespread appli...Solid-state polymer electrolytes are crucial for advancing solid-state lithium-metal batteries owing to their flexibility,excellent manufacturability,and strong interfacial compatibility.However,their widespread applications are hindered by low ionic conductivity at room temperature and lithium dendrite growth.Herein,we report a novel solid-state composite membrane electrolyte design that combines the vertically aligned channel structure and copolymer with a radial gradient composition.Within the vertically aligned channels,the composition of poly(vinyl ethylene carbonate-co-poly(ethylene glycol)diacrylate)(P(VEC-PEGDA)varies in a gradient along the radial direction:from the center to the wall of vertically aligned channels,the proportion of vinyl ethylene carbonate(VEC)in the copolymer decreases,while the proportion of poly(ethylene glycol)diacrylate(PEGDA)increases accordingly.It can be functionally divided into a mechanical-reinforcement layer and a fast-ion-conducting layer.The resulting solid-state composite membrane electrolyte achieves a high critical current density of 1.2 mA cm^(-2)and high ionic conductivity of 2.03 mS cm^(-1)at room temperature.Employing this composite membrane electrolyte,a Li//Li symmetric cell exhibits stable cycling for over 1850 h at 0.2 m A cm^(-2)/0.2 m A h cm^(-2),and a Li//LiFePO4(LFP)battery maintains 77.3% capacity retention at 2 C after 300 cycles.Our work provides insight into the rational design of safer and more efficient solidstate batteries through electrolyte structural engineering.展开更多
BACKGROUND Pathological calcification is a common feature of many diseases.Calcifying nanoparticles(CNPs)are considered potential inducers of this abnormal calcification,but their specific effects on bone marrow mesen...BACKGROUND Pathological calcification is a common feature of many diseases.Calcifying nanoparticles(CNPs)are considered potential inducers of this abnormal calcification,but their specific effects on bone marrow mesenchymal stem cells(BMSCs)remain unclear.BMSCs are key cells in bone formation and repair,and their aberrant apoptosis and calcification are closely related to disease progression.AIM To explore whether CNPs can induce apoptosis and calcification in BMSCs and analyzed the relationship between these processes.The differential effects of CNPs and nanoscale hydroxyapatites(nHAPs)in inducing apoptosis and calcification in BMSCs were also compared.METHODS CNPs obtained in the early stage were identified by electron microscopy and particle size analysis.BMSCs were cultured with various treatments,including different concentrations of nHAPs,CNPs[2 McFarland(MCF)turbidity,4 MCF,6 MCF],and a transforming growth factor(TGF)-βinhibitor(SB431542)for 72 hours.The isolated CNPs exhibited the expected sizes and shapes.RESULTS Exposure to CNPs and nHAPs suppressed cell proliferation and promoted apoptosis in a concentration-dependent manner,with CNPs exhibiting significantly stronger effects.Alizarin Red staining indicated an increase in calcium deposition with exposure to increasing concentrations of nHAPs and CNPs.Quantitative reverse-transcription polymerase chain reaction results indicated that medium concentrations of nHAPs and CNPs significantly enhanced the expression of pro-apoptotic and pro-calcification markers,whereas the expression of anti-apoptotic Bcl-2 was reduced compared with untreated controls.Western blotting results showed that medium concentrations of CNPs and nHAPs increased the expression of osteopontin,bone morphogenetic protein-2,TGF-β/Smad,Bax,and caspase-3 and decreased Bcl-2 expression compared with controls.CONCLUSION CNPs and nHAPs induced apoptosis and calcification in BMSCs,with CNPs being the most potent.Additionally,the TGF-βinhibitor SB431542 significantly reduced the occurrence of apoptosis and calcification.A correlation was found between apoptosis and calcification,which is likely mediated through the TGF-β/Smad signaling pathway.展开更多
Magnesium alloy wires were processed by micro-arc oxidation （MAO） in a modified silicate-phosphate composite electrolyte containing hydroxyapatite （HA） nanopowders and NaOH. Effects of NaOH content in the composit...Magnesium alloy wires were processed by micro-arc oxidation （MAO） in a modified silicate-phosphate composite electrolyte containing hydroxyapatite （HA） nanopowders and NaOH. Effects of NaOH content in the composite electrolyte on the microstructure and properties of the MAO ceramic coatings on magnesium alloy wires were studied. It is found that the arc voltage of magnesium alloy wires in the micro-arc oxidation process is significantly reduced while the oxidation rate is accelerated. Addition of 2 g/L NaOH in the composite electrolyte is a better choice for improving corrosion resistance of magnesium alloy wires. During early simulated body fluids （SBF） immersion, the micro-arc oxidized magnesium alloy wires undergo a slow and stable degradation. After soaking for 28 d, the protective ceramic coating still shows no damage but significant degradation is observed for magnesium alloy wires after immersion for more than 60 d.展开更多
The mesoporous hydroxyapatite （HA） was synthesized by hydrothermal method utilizing cationic surfactant cetyltrimethylammonium bromide （CTAB） as template. The crystalline phase, morphology and porous structure wer...The mesoporous hydroxyapatite （HA） was synthesized by hydrothermal method utilizing cationic surfactant cetyltrimethylammonium bromide （CTAB） as template. The crystalline phase, morphology and porous structure were characterized respectively by different detecting techniques. The results reveal that the particles are highly crystalline hydroxyapatite phase. The surfactant has little influence on the morphology of the crystals, but affects the porous structure obviously. The sample without CTAB has a low surface area not exceeding 33 m^2/g, and no distinct pores can be observed by TEM. While the samples obtained with the surfactant get better parameters. Numerous open-ended pores centered at 2-7 nm spread unequally on the surface of the hydroxyapatite nanorods. The N2 adsorption-desorption experiments show type IV isotherms with distinct hysteresis loops, illustrating the presence of mesoporous structure. When the mole ratio of CTAB to HA is 1：2, the sample has the largest surface area of 97.1 m^2/g and pore volume of 0.466 cm^3/g.展开更多
In order to further improve the transfection efficiency of hydroxyapatite nanoparticle （HAp）, arginine functionalized hydroxyapatite （HAp/Arg） was synthesized by hydrothermal synthesis. The morphology, crystallite...In order to further improve the transfection efficiency of hydroxyapatite nanoparticle （HAp）, arginine functionalized hydroxyapatite （HAp/Arg） was synthesized by hydrothermal synthesis. The morphology, crystallite size and zeta potential of the HAp/Arg were characterized by transmission electron microscopy （TEM）, atomic force microscopy （AFM） and zeta potential analyzer. The loading and protecting properties of HAp/Arg to DNA were tested by electrophoresis. Its cytotoxicity was also measured in Hela cells and HAEC cells by MTT and LDH, and its transfection efficiency was examined by fluorescence microscope and flow cytometry. The results reveal that HAp/Arg is short rod-like and nano single crystal, the mean diameter is 50-90 nm and zeta potential is 35.8 mV at pH 7.4. HAp/Arg to DNA can be condensed by electrostatic effect and protect DNA against degradation in DNase I, and shows high transfection efficiency without cytotoxicity. These results suggest that HAp/Arg can be a promising alternative as a novel gene delivery system.展开更多
The mixture of CaHPO 4·2H 2O and CaCO 3 was ground in an aqueous system under appropriate conditions to investigate the mechanochemical reaction for the synthesis of crystalline hydroxyapatite (HA) powder. Hyd...The mixture of CaHPO 4·2H 2O and CaCO 3 was ground in an aqueous system under appropriate conditions to investigate the mechanochemical reaction for the synthesis of crystalline hydroxyapatite (HA) powder. Hydroxyapatite of high crystallinity powder including trace Ca 10 (PO 4) 6CO 3(OH) and Ca 9HPO 4(PO 4) 6OH can be synthesized by mechanical activation without further thermal treatment at a high temperature. The synthesis reaction during the grinding process was almost completed within 1h. The as-ground powder exhibits a particle distribution of 20-100nm in size with a spherical or rodlike morphology. The composition and degree of crystallinity of the mechanochemical synthesized hydroxyapatite powders were coincident with the cement-type hydroxyapatite.展开更多
The arginine-modified and europium-doped hydroxyapatite nanoparticles（HAP-Eu） were synthesized by hydrothermal synthesis.The prepared nanoparticles were characterized by transmission electron microscopy（TEM）,X-ray...The arginine-modified and europium-doped hydroxyapatite nanoparticles（HAP-Eu） were synthesized by hydrothermal synthesis.The prepared nanoparticles were characterized by transmission electron microscopy（TEM）,X-ray diffractometry（XRD）,Fourier transform infrared（FTIR） and zeta potential analyzer.The cell viability of HAP-Eu was tested by image flow cytometry.The results indicated that HAP-Eu is short column shapes and its size is approximately 100 nm,its zeta potential is about 30.10 mV at pH of 7.5,and shows no cytotoxicity in human epithelial cells and endothelial cells.展开更多
Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These...Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These powders were proved nanopaticles by transmission electron microscope. The effects on proliferation of periodontal ligament cell(PDLC) were observed in vitro with MTT [3-(4,5dimethylthiazo;-2-yl)-2,5-diphenytetralium bromide] method. Results: On the 2nd,3rd,4th day after treated with nanoparticles of hydroxyapatite, the proliferate activity of the PDLC increases significantly, compared with those with dense hydroxyaoatite and control but no significant difference could be found between the dense hydroxyapatite and the control. Conclusion: Nanophase hydroxyapatite can promote the regeneration of periodontal tissue.展开更多
Transparent, luminescent and functional nanocomposites demonstrate interesting optical and mechanical properties suitable for many optoelectronic applications. Transparent polymethyl methacrylate （PMMA） polymer nano...Transparent, luminescent and functional nanocomposites demonstrate interesting optical and mechanical properties suitable for many optoelectronic applications. Transparent polymethyl methacrylate （PMMA） polymer nanocornposites modified with thenoyl- trifluoroacetonate （TAA） were fabricated by in situ polymerization and used as hosts for homogenous dispersion of 3 mol.% Eu^3＋：Ca10（PO4）6（OH）2 （Eu^3＋：HA） hydroxyapatite -20 nm large nanocrystals. The emission, excitation and transmission spectra as well as the fluorescence decay rates of bare Eu^3＋：HA nanocrystallites, Eu^3＋：HA embedded in the PMMA and and Eu：HA embedded in the PMMA/TTA rtanocomposites were studied. The improvement of transparency was demonstrated with the addition of TTA as well as europium doped hydroxyapatites in comparison to pure PMMA matrix. The Judd-Ofelt analysis of f-f transitions of Eu^3＋：HA nanocrystallites, the PMMA/Eu^3＋：HA and the PMMA＋TTA/Eu^3＋：HA was performed to investigate the optical behavior of the polymeric composites.展开更多
文摘Biological apatites contain several elements as traces. In this work, Magnesium and fluorine co-substituted hydroxyapatites with the general formula Ca9Mg(PO4)6(OH)2-yFy, where y = 0, 0.5, 1, 1.5 and 2 were synthesized by the hydrothermal method. After calcination at 500℃, the samples were pressureless sintered between 950℃ and 1250℃. The substitution of F- for OH- had a strong influence on the densification behavior and mechanical properties of the materials. Below 1200℃, the density steeply decreased for y = 0.5 sample. XRD analysis revealed that compared to hydroxylfluorapatite containing no magnesium, the substituted hydroxyfluorapatites decomposed, and the nature of the decomposition products is tightly dependent on the fluorine content. The hardness, elastic modulus and fracture toughness of these materials were investigated by Vickers’s hardness testing. The highest values were 622 ± 4 GPa, 181 ± 1 GPa and 1.85 ± 0.06 MPa.m1/2, respectively.
文摘Hydroxyapatite nanoparticles(HAP NPs)were synthesized by a one‐step hydrothermal method.The surface of HAP NPs was grafted-SH and-COOH chelating groups via in situ surface‐modification with iminodiacetic acid(IDA)and 3‐mercaptopropyl trimethoxysilane(MPS)to afford dual surface‐capped nano‐amendment HAPIDA/MPS.The structure of HAP‐IDA/MPS was characterized,and its adsorption performance for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)was evaluated.The total adsorption capacity of 0.10 g HAP‐IDA/MPS nano‐amendment for Hg^(2+),Cu^(2+),Zn^(2+),Ni^(2+),Co^(2+),and Cd^(2+)with an initial mass concentration of 20 mg·L^(-1) reached 13.7 mg·g^(-1),about 4.3 times as much as that of HAP.Notably,HAP‐IDA/MPS nano‐amendment displayed the highest immobilization rate for Hg^(2+),possibly because of its chemical reaction with-SH to form sulfide,possessing the lowest solubility product constant among a variety of metal sulfides.
基金the Deanship of Research and Graduate Studies at King Khalid University for funding this work through Small Group Research Project under grant number RGP1/34/46 (RGP1/34/46)
文摘Biodegradable magnesium(Mg)alloys have received increased attention as temporary medical implants due to their mechanical properties and density,similar to natural bone.However,the fast corrosion of Mg alloys in a physiological condition limits their wide applications.Hence,hydroxyapatite(HAp)coatings on Mg alloys have attracted much attention to address this corrosion issue and enhance the surface functionalities.In this paper,we present a review of HAp coating strategies on Mg alloys,including the sol-gel method,hydrothermal treatment,biomimetic coating,electrochemical deposition,electrophoretic deposition,and plasma electrolytic oxidation technique,and their recent progress to enhance the surface characteristics of Mg alloys.This review focused on aspects of coating morphology,hybrid formulations,and how they influence corrosion behavior as well as in vitro and in vivo performance.Moreover,we have discussed the future prospects of HAp-coating strategies,emphasizing on multifunctional,hybrid,and smart coatings for next-generation implant materials.
文摘BACKGROUND Bone regeneration is a central focus of regenerative medicine,with applications in orthopedics and dentistry,particularly for treating bone defects caused by trauma,infection,or congenital anomalies.Synthetic biomaterials,often combined with fibrin derivatives,offer promising solutions for bone healing and restoration.AIM To Explore the increasingly important role of the association of synthetic biomaterials with fibrin in bone regeneration.METHODS Search terms included:“synthetic biomaterials AND fibrin sealant”,“hydroxyapatite AND fibrin sealant”,“tricalcium phosphate AND fibrin sealant”,and“synthetic biomaterials AND platelet-rich fibrin(PRF)”,resulting in 67 articles.After rigorous screening,21 articles met the inclusion criteria.RESULTS The reviewed studies assessed biomaterials like hydroxyapatite(HA),β-tricalcium phosphate(β-TCP),and fibrin-based products.Key findings highlighted the enhanced osteoconductivity and biocompatibility of HA andβ-TCP,especially when combined with fibrin sealants.These composites show significant potential for improving cellular adhesion,promoting osteogenic differentiation,and accelerating bone regeneration.The antimicrobial properties and structural support for cell growth of certain biomaterials indicate a promising potential for clinical applic-ations.CONCLUSION This systematic review emphasizes the growing role of fibrin-based biomaterials in bone regeneration and urges continued research to improve their clinical use for complex bone defects.
文摘Bone defects caused by trauma,infection,or congenital anomalies remain a significant challenge in orthopedic and dental practice,necessitating innovative strategies to enhance healing and functional restoration.This systematic review by Pagani et al synthesizes evidence on the synergistic role of synthetic biomaterials,such as hydroxyapatite(HA)andβ-tricalcium phosphate(β-TCP),combined with fibrin derivatives in bone regeneration.Analyzing 21 studies,the authors demonstrate that HA andβ-TCP composites exhibit superior osteoconductivity and biocompatibility when integrated with fibrin sealants or plateletrich fibrin,promoting cellular adhesion,osteogenic differentiation,and accelerated healing.While these studies underscore the potential of these biomaterialfibrin hybrids,limitations such as variability in fibrin preparation,lack of longterm data,and insufficient standardization hinder clinical translation.This editorial contextualizes these findings within the evolving landscape of regenerative medicine,emphasizing the need for optimized formulations,interdisciplinary collaboration,and robust clinical trials to bridge laboratory innovation to bedside application.
文摘The field of bone tissue engineering has experienced an increase in prevalence due to the inherent challenge of the natural regeneration of significant bone deformities.This investigation focused on the preparation of Three-Dimensional(3D)-printed Polycaprolactone(PCL)scaffolds with varying proportions of Nanohydroxyapatite(NHA)and Nanoclay(NC),and their physiochemical and biological properties were assessed.The mechanical properties of PCL are satisfactory;however,its hydrophobic nature and long-term degradation hinder its use in scaffold fabrication.NHA and NC have been employed to improve the hydrophilic characteristics,mechanical strength,adhesive properties,biocompatibility,biodegradability,and osteoconductive behavior of PCL.The morphology results demonstrated 3D-printed structures with interconnected rectangular macropores and proper nanoparticle distribution.The sample containing 70 wt%NC showed the highest porosity(65.98±2.54%),leading to an increased degradation rate.The compressive strength ranged from 10.65±1.90 to 84.93±9.93 MPa,which is directly proportional to the compressive strength of cancellous bone(2–12 MPa).The wettability,water uptake,and biodegradability of PCL scaffolds considerably improved as the amount of NC increased.The results of the cellular assays exhibited increased proliferation,viability,and adhesion of MG-63 cells due to the addition of NHA and NC to the scaffolds.Finally,according to the in vitro results,it can be concluded that 3D-printed samples with higher amounts of NC can be regarded as a suitable scaffold for expediting the regeneration process of bone defects.
文摘Hydroxyapatite (HA) is widely explored as a biocompatible filler to enhance the mechanical and functional properties of glass ionomer cements (GICs). HA of particle sizes 15 µm and 30 µm were added as a filler into a matrix, composed of calcium aluminosilicate GICs and Poly-acrylic acid (PAA) in varying ratios. The tested ratios were Glass:PAA = 2:1 and Glass:HA:PAA = 2:0.5:1 to improve the mechanical strength of a conventional GIC. Mechanical properties, including compressive, flexural, and diametral tensile strength were studied at different setting times. The compressive strength (CS) was improved with hydroxyapatite addition and prolonged setting time while diametral tensile strength (DTS) did not follow any specific trend. The flexural strength (FS) of the composite cement was increased with increasing setting time regardless of the particle size of hydroxyapatite. The FTIR spectra of hydroxyapatite of particle sizes 15 μm and 30 μm are similar but for HA-GIC composites, the FTIR spectra, the peak around 1460 cm−1 are due to C-H and the peak at 1553 cm−1 is due to calcium carboxylate with calcium in a bridging mode which would be an excellent material that chemically bonds to the tooth structure, making it effective for both restorative procedures and cavity fillings. Scanning electron microscopy (SEM) microstructural study revealed that the glass particles were wrenched out, which was a cohesive fracture. The X-ray diffraction (XRD) pattern showed that the hydroxyapatite has a crystalline single-phase, hexagonal structure. The sharp peaks between the 2-theta range of 30 - 40 degrees are the same as in enamel powder. The spectra indicate the pure set cement as amorphous since there is no prominent peak, but with the addition of hydroxyapatite filler, the peak in the 2-theta range of 20 - 35 degrees is ascribed to crystalline apatite structure. The results indicate that incorporating hydroxyapatite into GIC significantly enhances its mechanical properties and structural integrity, suggesting its potential as an improved material for dental and restorative applications.
基金financial support from FAPESP-Sao Paulo Research Foundation[grants #2020/07923-0,and #2023/11076-0]the National Council for Scientific and Technological Development-CNPq[grant #406514/2021-6].
文摘Tissue engineering holds promise in developing materials for biological applications,such as bone tissue repair.This study focuses on bioabsorbable and biocompatible polymers like Poly(L-lactic acid)(PLLA),Polyurethane(PU),and Polycaprolactone(PCL),along with nanohydroxyapatite(nHA),an essential osteoconductive ceramic.The main objective was the development and characterization of scaffolds obtained by Rotary Jet Spinning(RJS)using PLLA,PU,and PCL incorporated with nHA,for bone-related applications.The resulting scaffolds exhibited uniform fiber morphology and a rough surface,ideal for effective bone-tissue interaction.The crystallinity indicated the scaffolds’bioactivity by apatite deposition in simulated body fluid.In addition,in vitro biological assays using preosteoblastic cells showed the biocompatibility of cells based on cell viability and adhesion parameters on the scaffolds.The results underscore the capacity of scaffolds incorporating nHA to promote both cell proliferation and osteoconduction,which are key elements essential for achieving effective bone regeneration.
基金supported by the National Key Research and Development Program of China(No.2019YFA0110600)the Science and Technology Support Program of Sichuan Province(No.2019YJ0161).
文摘Hierarchical porous structure,which include macropores,minor pores,and micropores in scaffolds,are essential in the multiple biological functions of bone repair and regeneration.In this study,patientcustomized calcium-deficient hydroxyapatite(CDHA)scaffolds with three-level hierarchical porous structure were fabricated by indirect 3D printing technology and particulate leaching method.The sacrificial template scaffolds were fabricated using a photo-curing 3D printer,which provided a prerequisite for the integral structure and interconnected macropores of CDHA scaffolds.Additionally,20 wt%pore former was incorporated into the slurry to enhance the content of smaller pores within the CDHA-2 scaffolds,and then the CDHA-2 scaffolds were sintered to remove the sacrificial template scaffolds and pore former.The obtained CDHA-2 scaffolds exhibited interconnected macropores(300-400μm),minor pores(∼10-100μm),and micropores(<10μm)distributed throughout the scaffolds,which could promote bone tissue ingrowth,increase surface roughness,and enhance protein adsorption of scaffolds.In vitro studies identified that CDHA-2 scaffolds had nanocrystal grains,high specific surface area,and outstanding protein adsorption capacity,which could provide a microenvironment for cell adhesion,spreading,and proliferation.In addition,the murine intramuscular implantation experiment suggested that CDHA-2 scaffolds exhibited excellent osteoinductivity and were superior to traditional BCP ceramics under conditions without the addition of live cells and exogenous growth factors.The rabbit calvarial defect repair results indicated that CDHA-2 scaffolds could enhance in situ bone regeneration.In conclusion,these findings demonstrated that the hierarchical porous structure of CDHA scaffolds was a pivotal factor in modulating osteoinductivity and bone regeneration,and CDHA-2 scaffolds were potential candidates for bone regeneration.
基金supported by the National Natural Science Foundation of China(52372099,52202328,22461142135,22479046)the Shanghai Sailing Program(22YF1455500)the Shanghai Magnolia Talent Plan Pujiang Project(24PJD128)。
文摘Solid-state polymer electrolytes are crucial for advancing solid-state lithium-metal batteries owing to their flexibility,excellent manufacturability,and strong interfacial compatibility.However,their widespread applications are hindered by low ionic conductivity at room temperature and lithium dendrite growth.Herein,we report a novel solid-state composite membrane electrolyte design that combines the vertically aligned channel structure and copolymer with a radial gradient composition.Within the vertically aligned channels,the composition of poly(vinyl ethylene carbonate-co-poly(ethylene glycol)diacrylate)(P(VEC-PEGDA)varies in a gradient along the radial direction:from the center to the wall of vertically aligned channels,the proportion of vinyl ethylene carbonate(VEC)in the copolymer decreases,while the proportion of poly(ethylene glycol)diacrylate(PEGDA)increases accordingly.It can be functionally divided into a mechanical-reinforcement layer and a fast-ion-conducting layer.The resulting solid-state composite membrane electrolyte achieves a high critical current density of 1.2 mA cm^(-2)and high ionic conductivity of 2.03 mS cm^(-1)at room temperature.Employing this composite membrane electrolyte,a Li//Li symmetric cell exhibits stable cycling for over 1850 h at 0.2 m A cm^(-2)/0.2 m A h cm^(-2),and a Li//LiFePO4(LFP)battery maintains 77.3% capacity retention at 2 C after 300 cycles.Our work provides insight into the rational design of safer and more efficient solidstate batteries through electrolyte structural engineering.
基金Supported by the Project of Xinjiang Production and Construction Corps,No.2022ZD090the Project of Xinjiang Production and Construction Corps-Young Science and Technology Innovation Talents,No.2023CB008-31+2 种基金The First Affiliated Hospital of Shihezi University Medical College,Doctoral Fund Project,No.BS202207Talent Development Fund-Tianshan Talents,No.CZ0012192024 National Health Commission Central Asian High-Incidence Prevention and Control Key Laboratory,No.KF202405.
文摘BACKGROUND Pathological calcification is a common feature of many diseases.Calcifying nanoparticles(CNPs)are considered potential inducers of this abnormal calcification,but their specific effects on bone marrow mesenchymal stem cells(BMSCs)remain unclear.BMSCs are key cells in bone formation and repair,and their aberrant apoptosis and calcification are closely related to disease progression.AIM To explore whether CNPs can induce apoptosis and calcification in BMSCs and analyzed the relationship between these processes.The differential effects of CNPs and nanoscale hydroxyapatites(nHAPs)in inducing apoptosis and calcification in BMSCs were also compared.METHODS CNPs obtained in the early stage were identified by electron microscopy and particle size analysis.BMSCs were cultured with various treatments,including different concentrations of nHAPs,CNPs[2 McFarland(MCF)turbidity,4 MCF,6 MCF],and a transforming growth factor(TGF)-βinhibitor(SB431542)for 72 hours.The isolated CNPs exhibited the expected sizes and shapes.RESULTS Exposure to CNPs and nHAPs suppressed cell proliferation and promoted apoptosis in a concentration-dependent manner,with CNPs exhibiting significantly stronger effects.Alizarin Red staining indicated an increase in calcium deposition with exposure to increasing concentrations of nHAPs and CNPs.Quantitative reverse-transcription polymerase chain reaction results indicated that medium concentrations of nHAPs and CNPs significantly enhanced the expression of pro-apoptotic and pro-calcification markers,whereas the expression of anti-apoptotic Bcl-2 was reduced compared with untreated controls.Western blotting results showed that medium concentrations of CNPs and nHAPs increased the expression of osteopontin,bone morphogenetic protein-2,TGF-β/Smad,Bax,and caspase-3 and decreased Bcl-2 expression compared with controls.CONCLUSION CNPs and nHAPs induced apoptosis and calcification in BMSCs,with CNPs being the most potent.Additionally,the TGF-βinhibitor SB431542 significantly reduced the occurrence of apoptosis and calcification.A correlation was found between apoptosis and calcification,which is likely mediated through the TGF-β/Smad signaling pathway.
基金Project (BE2011778) supported by Science and Technology Support Program of Jiangsu Province,ChinaProjects (CityU 112510,112212) supported by Hong Kong Research Grants Council (RGC) General Research Funds (GRF) ,China
文摘Magnesium alloy wires were processed by micro-arc oxidation （MAO） in a modified silicate-phosphate composite electrolyte containing hydroxyapatite （HA） nanopowders and NaOH. Effects of NaOH content in the composite electrolyte on the microstructure and properties of the MAO ceramic coatings on magnesium alloy wires were studied. It is found that the arc voltage of magnesium alloy wires in the micro-arc oxidation process is significantly reduced while the oxidation rate is accelerated. Addition of 2 g/L NaOH in the composite electrolyte is a better choice for improving corrosion resistance of magnesium alloy wires. During early simulated body fluids （SBF） immersion, the micro-arc oxidized magnesium alloy wires undergo a slow and stable degradation. After soaking for 28 d, the protective ceramic coating still shows no damage but significant degradation is observed for magnesium alloy wires after immersion for more than 60 d.
基金Projects(51102285,81170912)supported by the National Natural Science Foundation of ChinaProject supported by the Open Foundation of State Key Laboratory of Powder Metallurgy,China
文摘The mesoporous hydroxyapatite （HA） was synthesized by hydrothermal method utilizing cationic surfactant cetyltrimethylammonium bromide （CTAB） as template. The crystalline phase, morphology and porous structure were characterized respectively by different detecting techniques. The results reveal that the particles are highly crystalline hydroxyapatite phase. The surfactant has little influence on the morphology of the crystals, but affects the porous structure obviously. The sample without CTAB has a low surface area not exceeding 33 m^2/g, and no distinct pores can be observed by TEM. While the samples obtained with the surfactant get better parameters. Numerous open-ended pores centered at 2-7 nm spread unequally on the surface of the hydroxyapatite nanorods. The N2 adsorption-desorption experiments show type IV isotherms with distinct hysteresis loops, illustrating the presence of mesoporous structure. When the mole ratio of CTAB to HA is 1：2, the sample has the largest surface area of 97.1 m^2/g and pore volume of 0.466 cm^3/g.
基金Project(2013SK2024)supported by the Key Projects in Social Development Pillar Program of Hunan Province,ChinaProject(20130162120094)supported by Specialized Research Fund for the Doctoral Program of Higher Education(SRFDP),Ministry of Education,ChinaProjects(81071869,51305464)supported by the National Natural Science Foundation of China
文摘In order to further improve the transfection efficiency of hydroxyapatite nanoparticle （HAp）, arginine functionalized hydroxyapatite （HAp/Arg） was synthesized by hydrothermal synthesis. The morphology, crystallite size and zeta potential of the HAp/Arg were characterized by transmission electron microscopy （TEM）, atomic force microscopy （AFM） and zeta potential analyzer. The loading and protecting properties of HAp/Arg to DNA were tested by electrophoresis. Its cytotoxicity was also measured in Hela cells and HAEC cells by MTT and LDH, and its transfection efficiency was examined by fluorescence microscope and flow cytometry. The results reveal that HAp/Arg is short rod-like and nano single crystal, the mean diameter is 50-90 nm and zeta potential is 35.8 mV at pH 7.4. HAp/Arg to DNA can be condensed by electrostatic effect and protect DNA against degradation in DNase I, and shows high transfection efficiency without cytotoxicity. These results suggest that HAp/Arg can be a promising alternative as a novel gene delivery system.
文摘The mixture of CaHPO 4·2H 2O and CaCO 3 was ground in an aqueous system under appropriate conditions to investigate the mechanochemical reaction for the synthesis of crystalline hydroxyapatite (HA) powder. Hydroxyapatite of high crystallinity powder including trace Ca 10 (PO 4) 6CO 3(OH) and Ca 9HPO 4(PO 4) 6OH can be synthesized by mechanical activation without further thermal treatment at a high temperature. The synthesis reaction during the grinding process was almost completed within 1h. The as-ground powder exhibits a particle distribution of 20-100nm in size with a spherical or rodlike morphology. The composition and degree of crystallinity of the mechanochemical synthesized hydroxyapatite powders were coincident with the cement-type hydroxyapatite.
基金Project (81071869) supported by the National Natural Science Foundation of China Project (2009637526) supported by China Scholarship Council (CSC Program)Project (2010QZZD006) supported by the Key Program of Central South University Advancing Front Foundation
文摘The arginine-modified and europium-doped hydroxyapatite nanoparticles（HAP-Eu） were synthesized by hydrothermal synthesis.The prepared nanoparticles were characterized by transmission electron microscopy（TEM）,X-ray diffractometry（XRD）,Fourier transform infrared（FTIR） and zeta potential analyzer.The cell viability of HAP-Eu was tested by image flow cytometry.The results indicated that HAP-Eu is short column shapes and its size is approximately 100 nm,its zeta potential is about 30.10 mV at pH of 7.5,and shows no cytotoxicity in human epithelial cells and endothelial cells.
文摘Objective:To investigate possible effects of nanophase powder of hydroxyapatite on proliferation of periodontal ligament cells. Methods: With sol-gel method, the nanophase hydroxyapatite powders were fabricated. These powders were proved nanopaticles by transmission electron microscope. The effects on proliferation of periodontal ligament cell(PDLC) were observed in vitro with MTT [3-(4,5dimethylthiazo;-2-yl)-2,5-diphenytetralium bromide] method. Results: On the 2nd,3rd,4th day after treated with nanoparticles of hydroxyapatite, the proliferate activity of the PDLC increases significantly, compared with those with dense hydroxyaoatite and control but no significant difference could be found between the dense hydroxyapatite and the control. Conclusion: Nanophase hydroxyapatite can promote the regeneration of periodontal tissue.
基金Project supported by Polish Ministry of National Education (N N507 584938)
文摘Transparent, luminescent and functional nanocomposites demonstrate interesting optical and mechanical properties suitable for many optoelectronic applications. Transparent polymethyl methacrylate （PMMA） polymer nanocornposites modified with thenoyl- trifluoroacetonate （TAA） were fabricated by in situ polymerization and used as hosts for homogenous dispersion of 3 mol.% Eu^3＋：Ca10（PO4）6（OH）2 （Eu^3＋：HA） hydroxyapatite -20 nm large nanocrystals. The emission, excitation and transmission spectra as well as the fluorescence decay rates of bare Eu^3＋：HA nanocrystallites, Eu^3＋：HA embedded in the PMMA and and Eu：HA embedded in the PMMA/TTA rtanocomposites were studied. The improvement of transparency was demonstrated with the addition of TTA as well as europium doped hydroxyapatites in comparison to pure PMMA matrix. The Judd-Ofelt analysis of f-f transitions of Eu^3＋：HA nanocrystallites, the PMMA/Eu^3＋：HA and the PMMA＋TTA/Eu^3＋：HA was performed to investigate the optical behavior of the polymeric composites.
