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(HA)nanoparticles impart outstanding mechanical properties to organicinorganic nanocomposites in bone.Inspired by the composite structure of HA nanoparticles and collagen in bone,a high performance HA/ge...Hydroxyapatite(HA)nanoparticles impart outstanding mechanical properties to organicinorganic nanocomposites in bone.Inspired by the composite structure of HA nanoparticles and collagen in bone,a high performance HA/gelatin nanocomposite was first developed.The nanocomposites have much better mechanical properties(elongation at break 29.9%,tensile strength 90.7 MPa,Young’s modulus 5.24 GPa)than pure gelatin films(elongation at break 9.3%,tensile strength 90.8 MPa,Young’s modulus 2.5 GPa).In addition,the composite films keep a high transmittance in visible wavelength range from 0%to 60%of the HA solid content.These differences in properties are attributed to the homogeneous distribution of HA nanoparticles in the gelatin polymer matrix and the strong interaction between the particle surfaces and the gelatin molecules.This protocol should be promising for HA-based nanocomposites with enhanced mechanical properties for biomedical applications.展开更多
Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body environment.This necessitates the synthesis of a suitable coating that may improve ...Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body environment.This necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical integrity.In this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(RGO)-calcium carbonate(CaCO_(3))composite coating.Detailed analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.展开更多
Composite biomaterials comprising polylactide(PLA)and hydroxyapatite(HA)are applied in bone,cartilage and dental regenerative medicine,where HA confers osteoconductive properties.However,after surgical implantation,ad...Composite biomaterials comprising polylactide(PLA)and hydroxyapatite(HA)are applied in bone,cartilage and dental regenerative medicine,where HA confers osteoconductive properties.However,after surgical implantation,adverse immune responses to these composites can occur,which have been attributed to size and morphology of HA particles.Approaches to effectively modulate these adverse immune responses have not been described.PLA degradation products have been shown to alter immune cell metabolism(immunometabolism),which drives the inflammatory response.Accordingly,to modulate the inflammatory response to composite biomaterials,inhibitors were incorporated into composites comprised of amorphous PLA(aPLA)and HA(aPLA+HA)to regulate glycolytic flux.Inhibition at specific steps in glycolysis reduced proinflammatory(CD86+CD206-)and increased pro-regenerative(CD206+)immune cell populations around implanted aPLA+HA.Notably,neutrophil and dendritic cell(DC)numbers along with proinflammatory monocyte and macrophage populations were decreased,and Arginase 1 expression among DCs was increased.Targeting immunometabolism to control the proinflammatory response to biomaterial composites,thereby creating a pro-regenerative microenvironment,is a significant advance in tissue engineering where immunomodulation enhances osseointegration and angiogenesis,which could lead to improved bone regeneration.展开更多
The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal...The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic performance.The results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of hydroxyapatite.The[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of hydroxyapatite.High fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of hydroxyapatite.The hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic performance.The suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of N_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali.展开更多
In this study,a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PEO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(S...In this study,a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PEO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(S.aureus),was impregnated into the coating.Samples with vancomycin showed high bactericidal activity against S.aureus.The mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were performed.According to SEM,EDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high biocompatibility.The analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the samples.During electrochemical tests,an increase in corrosion resistance by more than two times after the application of PEO coatings was revealed.According to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by encapsulation.Antibiotic release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day 28.Throughout the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.展开更多
Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and t...Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic strength.However,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP nanospheres.Furthermore,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like crystals.These results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.展开更多
Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioacti...Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioactiv-ityregardingbonedefectregeneration.Inthisstudy,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal conditions.Specifically,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal environment.The result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial activity.We then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of CNT.In addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,respectively.Finally,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells).展开更多
Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_...Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively.展开更多
Calcium-based biocomposite materials have a pivotal role in the biomedical field with their diverse properties and applications in combating challenging medical problems. The study states the development and character...Calcium-based biocomposite materials have a pivotal role in the biomedical field with their diverse properties and applications in combating challenging medical problems. The study states the development and characterization of Calcium-based biocomposites: Hydroxyapatite (HAP), and PVA-Gelatin-HAP films. For the preparation of Calcium-based biocomposites, an unconventional source, the waste material calcite stone, was used as calcium raw material, and by the process of calcination, calcium oxide was synthesized. From calcium oxide, HAP was prepared by chemical precipitation method, which was later added in different proportions to PVA-Gelatin solution and finally dried to form biocomposite films. Then the different properties of PVA/Gelatin/HAP composite, for instance, chemical, mechanical, thermal, and swelling properties due to the incorporation of various proportions of HAP in PVA-Gelatin solution, were investigated. The characterization of the HAP was conducted by X-ray Diffraction Analysis, and the characterization of HAP-PVA-Gelatin composites was done by Fourier Transform Infrared Spectroscopy, Thermomechanical Analysis, Tensile test, Thermogravimetric Differential Thermal Analysis, and Swelling Test. The produced biocomposite films might have applications in orthopedic implants, drug delivery, bone tissue engineering, and wound healing.展开更多
Solid polymer electrolytes(SPEs)are one of the most promising alternatives to flammable liquid electrolytes for building safe Li metal batteries.Nevertheless,the poor ionic conductivity at room temperature(RT)and low ...Solid polymer electrolytes(SPEs)are one of the most promising alternatives to flammable liquid electrolytes for building safe Li metal batteries.Nevertheless,the poor ionic conductivity at room temperature(RT)and low resistance to Li dendrites seriously hinder the commercialization of SPEs.Herein,we design a bifunctional flame retardant SPE by combining hydroxyapatite(HAP)nanomaterials with Nmethyl pyrrolidone(NMP)in the PVDF-HFP matrix.The addition of HAP generates a hydrogen bond network with the PVDF-HFP matrix and cooperates with NMP to facilitate the dissociation of Li TFSI in the PVDF-HFP matrix.Consequently,the prepared SPE demonstrates superior ionic conductivity at RT,excellent fireproof properties,and strong resistance to Li dendrites.The assembled Li symmetric cell with prepared SPE exhibits a stable cycling performance of over 1200 h at 0.2 m A cm^(-2),and the solid-state LiFePO_4||Li cell shows excellent capacity retention of 85.3%over 600 cycles at 0.5 C.展开更多
In this study, the biocompatible protective coating was formed using plasma electrolytic oxidation(PEO) on bioresorbable Mg-0.8Ca alloy. The composition of the formed coating was studied using XRD, SEM-EDX analysis, a...In this study, the biocompatible protective coating was formed using plasma electrolytic oxidation(PEO) on bioresorbable Mg-0.8Ca alloy. The composition of the formed coating was studied using XRD, SEM-EDX analysis, and micro-Raman spectroscopy. The uniform distribution of hydroxyapatite over the thickness of protective PEO-layer was established. Using traditional(EIS, PDP, OCP) and local scanning electrochemical methods(SVET, SIET with H^(+)-selective microelectrode), the level of protective properties of PEO-layer in a biological environment(mammalian cell culture medium, MEM) was determined. It was established that modification of Mg-0.8Ca alloy surface by PEO contributes to a significant increase in the corrosion resistance of the surface layer, making it possible to control the process of material‘s biodegradation. The maximum local electrochemical activity was recorded after 72 h of testing, while for the uncoated sample,intense corrosion degradation was recorded in the first 12 min of exposure to the cell culture medium. Formation of the PEO-coating results in a twofold decrease in the corrosion current density(2.8·10^(-6)A cm^(-2)) and an increase in the impedance modulus measured at a low frequency(1.7·10^(4)Ω cm^(2)) in comparison with the uncoated material(9.5·10^(-6)A cm^(-2);8.1·10^(3)Ω cm^(2)). The mechanism of material bioresorption was established and a model for biodegradation process of Mg-0.8Ca alloy with hydroxyapatite-containing PEO-coating in MEM was proposed. Analysis of these results and comparing with others obtained by various scientific groups indicate the prospects for application of biocompatible PEO-coating on Mg-Ca alloy in implant surgery.展开更多
Methacrylic acid,an important organic chemical,is commercially manufactured starting from fossil feedstock.The decarboxylation of itaconic acid derived for biomass is a green route to the synthesis of methacrylic acid...Methacrylic acid,an important organic chemical,is commercially manufactured starting from fossil feedstock.The decarboxylation of itaconic acid derived for biomass is a green route to the synthesis of methacrylic acid.In view of the problems existing in the researches on this route such as use of noble metal catalyst,harsh reaction conditions and low desired-product yield,we prepared a series of hydroxyapatite catalysts with different Ca/P molar ratios and evaluated their catalytic performance.The results showed that the hydroxyapatite catalyst with a Ca/P molar ratio of 1.58 had the best catalytic activity.The highest yield of MAA up to 61.2%was achieved with basically complete conversion of itaconic acid under the suitable reaction conditions of 1 equivalent of NaOH,2 MPa of N_(2),250℃,and 2 h.On this basis,a reaction network for the decarboxylation of itaconic acid to methacrylic acid catalyzed by hydroxyapatite was established.With the aid of catalyst characterization using X-ray powder diffraction,NH3/CO2 temperature-programmed desorption,N_(2)physisorption,inductively coupled plasma optical emission spectrometry,and scanning electron microscopy,we found that the distribution of surface acid sites and basic sites,crystal growth orientation,texture properties and morphology of hydroxyapatite varied with the Ca/P molar ratio.Furthermore,the change of the crystal growth orientation and its influence on the surface acidity and alkalinity were clarified.展开更多
The mechanics-corrosion and strength-ductility tradeoffs of magnesium(Mg)alloys have limited their applications in fields such as orthopedic implants.Herein,a fine-grain structure consisting of weak anodic nano-lamell...The mechanics-corrosion and strength-ductility tradeoffs of magnesium(Mg)alloys have limited their applications in fields such as orthopedic implants.Herein,a fine-grain structure consisting of weak anodic nano-lamellar solute-enriched stacking faults(SESFs)with the average thickness of 8 nm and spacing of 16 nm is constructed in an as-extruded Mg96.9Y1.2Ho1.2Zn0.6Zr0.1(at.%)alloy,obtaining a high yield strength(YS)of 370 MPa,an excellent elongation(EL)of 17%,and a low corrosion rate of 0.30 mm y−1(close to that of high-pure Mg)in a uniform corrosion mode.Through scanning Kelvin probe force microscopy(SKPFM),one-dimensional nanostructured SESFs are identified as the weak anode(∼24 mV)for the first time.The excellent corrosion resistance is mainly related to the weak anodic nature of SESFs and their nano-lamellar structure,leading to the more uniform potential distribution to weaken galvanic corrosion and the release of abundant Y^(3+)/Ho^(3+)from SESFs to form a more protective film with an outer Ca_(10)(PO_(4))_(6)(OH)_(2)/Y_(2)O_(3)/Ho_(2)O_(3) layer(thickness percentage of this layer:72.45%).For comparison,the as-cast alloy containing block 18R long period stacking ordered(LPSO)phase and the heat-treated alloy with fine lamellar 18R-LPSO phase(thickness:80 nm,spacing:120 nm)are also studied,and the characteristics of SESFs and 18R-LPSO phase,such as the weak anode nature of the former and the cathode nature of the latter(37-90 mV),are distinguished under the same alloy composition.Ultimately,we put forward the idea of designing Mg alloys with high mechanical and anti-corrosion properties by constructing"homogeneous potential strengthening microstructure",such as the weak anode nano-lamellar SESFs structure.展开更多
Mg and its alloys have been introduced as promising biodegradable materials for biomedical implant applications due to their excellent biocompatibility, mechanical behavior, and biodegradability. However, their suscep...Mg and its alloys have been introduced as promising biodegradable materials for biomedical implant applications due to their excellent biocompatibility, mechanical behavior, and biodegradability. However, their susceptibility to rapid corrosion within the body poses a significant challenge and restricts their applications. To overcome this issue, various surface modification techniques have been developed to enhance the corrosion resistance and bioactivity of Mg-based implants. PEO is a potent technique for producing an oxide film on a surface that significantly minimizes the tendency to corrode. However, the inevitable defects due to discharges and poor biological activity during the coating process remain a concern. Therefore, adding suitable particles during the coating process is a suitable solution. Hydroxyapatite(HAp)has attracted much attention in the development of biomedical applications in the scientific community. HAp shows excellent biocompatibility due to its similarity in chemical composition to the mineral portion of bone. Therefore, its combination with Mg-based implants through PEO has shown significant improvements in their corrosion resistance and bioactivity. This review paper provides a comprehensive overview of the recent advances in the preparation, characterization, corrosion behavior and bioactivity applications of HAp particles on Mg-based implants by PEO.展开更多
Biomimetic bone-active coatings composed of inorganic nano-hydroxyapatite(i.e.,nHA)and organic silk fibroin(i.e.,SF)are layer-by-layer deposited on Mg-Zn-Ca alloy by a controllable ultrasonic spray method.Meanwhile,pl...Biomimetic bone-active coatings composed of inorganic nano-hydroxyapatite(i.e.,nHA)and organic silk fibroin(i.e.,SF)are layer-by-layer deposited on Mg-Zn-Ca alloy by a controllable ultrasonic spray method.Meanwhile,plasma activation is developed as a promising strategy to pretreat magnesium surfaces,which facilitates the direct adhesion of coatings with enhanced bonding interfaces.In this work,we engineer the nHA/SF composite coatings with excellent mechanical properties and adhesion force.The optimized parameters of ultrasonic spray bring significant influence on the surface morphologies of coatings.Assisted by hybrid plasma of oxygen and nitrogen(i.e.,O_(2)/N_(2) plasma),the activated Mg-Zn-Ca surfaces are uniformly covered by a robust and compact nHA/SF composite coating,establishing a multifunctional system with superior corrosion resistance and biological performance.Interestingly,secondary oxygen plasma treatment of nHA/SF coatings(A-nHA/SF)promotes the hydrophilicity,leading to a rapid self-repair effect from surface damage.The improvement of anti-corrosion and self-repair provides a dependable platform for better cell adhesion,proliferation,spreading and differentiation.These favorable factors contribute to the preferable in vivo biocompatibility and the promotion of newly formed bones for the A-nHA/SF-coated Mg implants.This study lays important foundations for coating strategy on biomedical magnesium alloy as multifunctional osteogenic system in bioactive implantable applications.展开更多
Immune adjuvants are immune modulators that have been developed in the context of infectious vaccinations.There is currently a growing interest in immune adjuvants due to the development of immunotherapy against cance...Immune adjuvants are immune modulators that have been developed in the context of infectious vaccinations.There is currently a growing interest in immune adjuvants due to the development of immunotherapy against cancers.Immune adjuvant mechanisms of action are focused on the initiation and amplification of the inflammatory response leading to the innate immune response,followed by the adaptive immune response.The main activity lies in the support of antigen presentation and the maturation and functions of dendritic cells.Most immune adjuvants are associated with a vaccine or incorporated into the new generation of m RNA vaccines.Few immune adjuvants are used as drugs.Hydroxyapatite(HA)ceramics and azoximer bromide(AZB)are overlooked molecules that were used in early clinical trials,which demonstrated clinical efficacy and excellent tolerance profiles.HA combined in an autologous vaccine was previously developed in the veterinary field for use in canine spontaneous lymphomas.AZB,an original immune modulator derived from a class of heterochain aliphatic polyamines that is licensed in Russia,the Commonwealth of Independent States,and Slovakia for infectious and inflammatory diseases,is and now being developed for use in cancer with promising results.These two immune adjuvants can be combined in various immunotherapy strategies.展开更多
Cancerous diseases and diseases resulting from bacteria and fungi are some of the pressures that humans face.Therefore,the development of biomaterials that are resistant to cancerous diseases,bacteria,and fungi has be...Cancerous diseases and diseases resulting from bacteria and fungi are some of the pressures that humans face.Therefore,the development of biomaterials that are resistant to cancerous diseases,bacteria,and fungi has become one of the requirements of the medical field to extend the life of the biomaterial and fight pathogens after implanting these materials inside the human body.One of the important biomaterials used in the field of orthopedics is hydroxyapatite.In this research,Nano substituted hydroxyapatite was prepared by the wet precipitation method,including replacing 5%of the calcium ions with neodymium,cerium,magnesium,and zinc ions in cationic substitution.Many tests were carried out to characterize the prepared material.The biological properties were evaluated by examining the resistance of the substituted hydroxyapatite to bacteria and fungi,in addition to testing the effect of the material on normal cells and bone cancer cells.The results showed a new structure of hydroxyapatite after the substitution process and a significant improvement in the biological properties of the prepared biomaterial compared to other researches.展开更多
Existing technologies used to detect monosodium urate(MSU)crystals for gout diagnosis are not ideal due to their low sensitivity and complexity of operation.The purpose of this study was to explore whether aggregation...Existing technologies used to detect monosodium urate(MSU)crystals for gout diagnosis are not ideal due to their low sensitivity and complexity of operation.The purpose of this study was to explore whether aggregation-induced emission luminogens(AIEgens)can be used for highly specific imaging of MSU crystals to assist in the diagnosis of gout.First,we developed a series of luminogens(i.e.,tetraphenyl ethylene(TPE)-NH_(2),TPE-2NH_(2),TPE-4NH_(2),TPE-COOH,TPE-2COOH,TPE-4COOH,and TPE-Ketoalkyne),each of which was then evenly mixed with MSU crystals.Next,optimal fluorescence imaging of each of the luminogens was characterized by a confocal laser scanning microscope(CLSM).This approach was used for imaging standard samples of MSU,hydroxyapatite(HAP)crystals,and mixed samples with 1:1 mass ratio of MSU/HAP.We also imaged samples from mouse models of acute gouty arthritis,HAP deposition disease,and comorbidities of interest.Subsequently,CLSM imaging results were compared with those of compensated polarized light microscopy,and we assessed the biosafety of TPE-Ketoalkyne in the RAW264.7 cell line.Finally,CLSM time series and three-dimensional imaging were performed on MSU crystal samples from human gouty synovial fluid and tophi.As a promising candidate for MSU crystal labeling,TPE-Ketoalkyne was found to detect MSU crystals accurately and rapidly in standard samples,animal samples,and human samples,and could precisely distinguish gout from HAP deposition disease.This work demonstrates that TPE-Ketoalkyne is suitable for highly specific and timely imaging of MSU crystals in gouty arthritis and may facilitate future research on MSU crystal-related diseases.展开更多
Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commerci...Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commercial temperature controlled microwave chemistry ovens (TCMC), digesters, and axial field helical antennae. For each of these microwave applicators the process energy budget where estimated (Watts multiplied by process time = kJ) and energy density (applied energy divided by suspension volume = kJ·ml<sup>-1</sup>) range between 180 ± 176.8 kJ, and 79.5 ± 79 kJ·ml<sup>-1</sup>, respectively. The axial field helical field an-tenna applicator is found to be the most energy efficient (0.253 kJ·m<sup>-1</sup> per kJ, at 36 W). Followed by microwave ovens (4.47 ± 3.9 kJ·ml<sup>-1</sup> per 76.83 ± 39 kJ), and TCMC ovens (2.86 ± 2.3 kJ·m<sup>-1</sup> per 343 ± 321.5 kJ). The digester applicators have the least energy efficiency (36.2 ± 50.7 kJ·m<sup>-1</sup> per 1010 ± 620 kJ). A comparison with reconstructed ‘non-thermal’ microwave oven inactivation microorganism experiments yields a power-law signature of n = 0.846 (R<sup>2</sup> = 0.7923) four orders of magnitude. The paper provides a discussion on the Au and Ag nanoparticle chemistry and bio-chemistry synthesis aspects of the microwave applicator energy datasets and variation within each dataset. The visual and analytical approach within the energy phase-space projection enables a nanoparticle synthesis route to be systematically characterized, and where changes to the synthesis are to be mapped and compared directly with historical datasets. In order to help identify lower cost nanoparticle synthesis, in addition to potentially reduce synthesis energy to routes informed changes to potentially reduce synthesis energy budget, along with nanoparticle morphology and yield.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.
基金Funded by the Natural Science Foundation of Hubei Province(No.2018CFB710)the Opening Fund of Hubei Provincial Key Laboratory of Green Materials for Light Industry(No.202107B07)Hubei University of Technology。
文摘Hydroxyapatite(HA)nanoparticles impart outstanding mechanical properties to organicinorganic nanocomposites in bone.Inspired by the composite structure of HA nanoparticles and collagen in bone,a high performance HA/gelatin nanocomposite was first developed.The nanocomposites have much better mechanical properties(elongation at break 29.9%,tensile strength 90.7 MPa,Young’s modulus 5.24 GPa)than pure gelatin films(elongation at break 9.3%,tensile strength 90.8 MPa,Young’s modulus 2.5 GPa).In addition,the composite films keep a high transmittance in visible wavelength range from 0%to 60%of the HA solid content.These differences in properties are attributed to the homogeneous distribution of HA nanoparticles in the gelatin polymer matrix and the strong interaction between the particle surfaces and the gelatin molecules.This protocol should be promising for HA-based nanocomposites with enhanced mechanical properties for biomedical applications.
文摘Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body environment.This necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical integrity.In this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(RGO)-calcium carbonate(CaCO_(3))composite coating.Detailed analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.
基金Funding for this work was provided in part by the James and Kathleen Cornelius Endowment at MSU.The Mass Spectrometry core at MSU,especially A.J.Schilmiller and J.O’Keefe,helped to analyze releasates.
文摘Composite biomaterials comprising polylactide(PLA)and hydroxyapatite(HA)are applied in bone,cartilage and dental regenerative medicine,where HA confers osteoconductive properties.However,after surgical implantation,adverse immune responses to these composites can occur,which have been attributed to size and morphology of HA particles.Approaches to effectively modulate these adverse immune responses have not been described.PLA degradation products have been shown to alter immune cell metabolism(immunometabolism),which drives the inflammatory response.Accordingly,to modulate the inflammatory response to composite biomaterials,inhibitors were incorporated into composites comprised of amorphous PLA(aPLA)and HA(aPLA+HA)to regulate glycolytic flux.Inhibition at specific steps in glycolysis reduced proinflammatory(CD86+CD206-)and increased pro-regenerative(CD206+)immune cell populations around implanted aPLA+HA.Notably,neutrophil and dendritic cell(DC)numbers along with proinflammatory monocyte and macrophage populations were decreased,and Arginase 1 expression among DCs was increased.Targeting immunometabolism to control the proinflammatory response to biomaterial composites,thereby creating a pro-regenerative microenvironment,is a significant advance in tissue engineering where immunomodulation enhances osseointegration and angiogenesis,which could lead to improved bone regeneration.
基金supported by National Natural Science Foundation of China(21978066)Basic Research Program of Hebei Province for Natural Science Foundation and Key Basic Research Project(18964308D)the Key Program of Natural Science Foundation of Hebei Province(B2020202048).
文摘The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic performance.The results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of hydroxyapatite.The[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of hydroxyapatite.High fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of hydroxyapatite.The hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic performance.The suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of N_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali.
基金supported by Russian Science Foundation Grant no.22-73-10149,https://rscf.ru/project/22-73-10149/supported by the Russian Science Foundation Grant no.23-13-00329,https://rscf.ru/project/23-13-00329/。
文摘In this study,a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PEO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(S.aureus),was impregnated into the coating.Samples with vancomycin showed high bactericidal activity against S.aureus.The mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were performed.According to SEM,EDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high biocompatibility.The analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the samples.During electrochemical tests,an increase in corrosion resistance by more than two times after the application of PEO coatings was revealed.According to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by encapsulation.Antibiotic release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day 28.Throughout the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.
基金Funded by the National Natural Science Foundation of China(No.52172287)the National Key Research and Development Program of China(No.2021YFA0715700)。
文摘Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic strength.However,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP nanospheres.Furthermore,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like crystals.These results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.
基金the National Natural Science Foundation of China(Nos.52275393 and 51935014)Hunan Provincial Natural Science Foundation of China(Nos.2021JJ20061,2020JJ3047,and 2019JJ50588)+4 种基金Jiangxi Provincial Natural Science Foundation of China(No.20224ACB204013)the Project of State Key Laboratory of High Performance Complex ManufacturingTechnology Innovation Platform Project of Shenzhen Institute of Information Technology 2020(No.PT2020E002)Guangdong Province Precision Manufacturing and Intelligent Production Education Integration Innovation Platform(No.2022CJPT019)Independent Exploration and Innovation Project of Central South University(No.1053320220553).
文摘Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioactiv-ityregardingbonedefectregeneration.Inthisstudy,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal conditions.Specifically,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal environment.The result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial activity.We then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of CNT.In addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,respectively.Finally,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells).
基金funded the World Class Research(WCR)Grant of Universitas Diponegoro with Contract Number 357-36/UN7.D2/PP/IV/2024.
文摘Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively.
文摘Calcium-based biocomposite materials have a pivotal role in the biomedical field with their diverse properties and applications in combating challenging medical problems. The study states the development and characterization of Calcium-based biocomposites: Hydroxyapatite (HAP), and PVA-Gelatin-HAP films. For the preparation of Calcium-based biocomposites, an unconventional source, the waste material calcite stone, was used as calcium raw material, and by the process of calcination, calcium oxide was synthesized. From calcium oxide, HAP was prepared by chemical precipitation method, which was later added in different proportions to PVA-Gelatin solution and finally dried to form biocomposite films. Then the different properties of PVA/Gelatin/HAP composite, for instance, chemical, mechanical, thermal, and swelling properties due to the incorporation of various proportions of HAP in PVA-Gelatin solution, were investigated. The characterization of the HAP was conducted by X-ray Diffraction Analysis, and the characterization of HAP-PVA-Gelatin composites was done by Fourier Transform Infrared Spectroscopy, Thermomechanical Analysis, Tensile test, Thermogravimetric Differential Thermal Analysis, and Swelling Test. The produced biocomposite films might have applications in orthopedic implants, drug delivery, bone tissue engineering, and wound healing.
基金supported by the National Natural Science Foundation of China (Grant Nos.51604089,51874110,22173066,21903058)the Natural Science Foundation of Heilongjiang Province (Grant No.YQ2021B004)Open Project of State Key Laboratory of Urban Water Resource and Environment (Grant No.QA202138)。
文摘Solid polymer electrolytes(SPEs)are one of the most promising alternatives to flammable liquid electrolytes for building safe Li metal batteries.Nevertheless,the poor ionic conductivity at room temperature(RT)and low resistance to Li dendrites seriously hinder the commercialization of SPEs.Herein,we design a bifunctional flame retardant SPE by combining hydroxyapatite(HAP)nanomaterials with Nmethyl pyrrolidone(NMP)in the PVDF-HFP matrix.The addition of HAP generates a hydrogen bond network with the PVDF-HFP matrix and cooperates with NMP to facilitate the dissociation of Li TFSI in the PVDF-HFP matrix.Consequently,the prepared SPE demonstrates superior ionic conductivity at RT,excellent fireproof properties,and strong resistance to Li dendrites.The assembled Li symmetric cell with prepared SPE exhibits a stable cycling performance of over 1200 h at 0.2 m A cm^(-2),and the solid-state LiFePO_4||Li cell shows excellent capacity retention of 85.3%over 600 cycles at 0.5 C.
基金Local electrochemical tests,biocompatible coating formation and modeling the mechanism of the material degradation were supported by the Grant of Russian Science Foundation,Russia (project no.21-73-10148,https://rscf.ru/en/project/ 21-73-10148/)The study of material‘s structure,composition,and kinetics of the corrosion processes using traditional electrochemical methods was supported by the Grant of Russian Science Foundation,Russia (project no.20-13-00130,https://rscf.ru/en/project/20-13-00130/)XRD data were acquired under the government assignments from the Ministry of Science and Higher Education of the Russian Federation,Russia (project no.FWFN(0205)-2022-0003)。
文摘In this study, the biocompatible protective coating was formed using plasma electrolytic oxidation(PEO) on bioresorbable Mg-0.8Ca alloy. The composition of the formed coating was studied using XRD, SEM-EDX analysis, and micro-Raman spectroscopy. The uniform distribution of hydroxyapatite over the thickness of protective PEO-layer was established. Using traditional(EIS, PDP, OCP) and local scanning electrochemical methods(SVET, SIET with H^(+)-selective microelectrode), the level of protective properties of PEO-layer in a biological environment(mammalian cell culture medium, MEM) was determined. It was established that modification of Mg-0.8Ca alloy surface by PEO contributes to a significant increase in the corrosion resistance of the surface layer, making it possible to control the process of material‘s biodegradation. The maximum local electrochemical activity was recorded after 72 h of testing, while for the uncoated sample,intense corrosion degradation was recorded in the first 12 min of exposure to the cell culture medium. Formation of the PEO-coating results in a twofold decrease in the corrosion current density(2.8·10^(-6)A cm^(-2)) and an increase in the impedance modulus measured at a low frequency(1.7·10^(4)Ω cm^(2)) in comparison with the uncoated material(9.5·10^(-6)A cm^(-2);8.1·10^(3)Ω cm^(2)). The mechanism of material bioresorption was established and a model for biodegradation process of Mg-0.8Ca alloy with hydroxyapatite-containing PEO-coating in MEM was proposed. Analysis of these results and comparing with others obtained by various scientific groups indicate the prospects for application of biocompatible PEO-coating on Mg-Ca alloy in implant surgery.
基金supported by the National Natural Science Foundation of China(Grant No.21978066)Basic Research Program of Hebei Province for Natural Science Foundation and Key Basic Research Project(Grant No.18964308D)the Key Program of Natural Science Foundation of Hebei Province(Grant No.B2020202048).
文摘Methacrylic acid,an important organic chemical,is commercially manufactured starting from fossil feedstock.The decarboxylation of itaconic acid derived for biomass is a green route to the synthesis of methacrylic acid.In view of the problems existing in the researches on this route such as use of noble metal catalyst,harsh reaction conditions and low desired-product yield,we prepared a series of hydroxyapatite catalysts with different Ca/P molar ratios and evaluated their catalytic performance.The results showed that the hydroxyapatite catalyst with a Ca/P molar ratio of 1.58 had the best catalytic activity.The highest yield of MAA up to 61.2%was achieved with basically complete conversion of itaconic acid under the suitable reaction conditions of 1 equivalent of NaOH,2 MPa of N_(2),250℃,and 2 h.On this basis,a reaction network for the decarboxylation of itaconic acid to methacrylic acid catalyzed by hydroxyapatite was established.With the aid of catalyst characterization using X-ray powder diffraction,NH3/CO2 temperature-programmed desorption,N_(2)physisorption,inductively coupled plasma optical emission spectrometry,and scanning electron microscopy,we found that the distribution of surface acid sites and basic sites,crystal growth orientation,texture properties and morphology of hydroxyapatite varied with the Ca/P molar ratio.Furthermore,the change of the crystal growth orientation and its influence on the surface acidity and alkalinity were clarified.
基金the support of the National Natural Science Foundation of China(51871069,52071093)the Zhejiang Province Key Research and Development Plan,China(2021C01086)Student Research and Innovation Fund of the Fundamental Research Funds for the Central Universities(3072022GIP1004)。
文摘The mechanics-corrosion and strength-ductility tradeoffs of magnesium(Mg)alloys have limited their applications in fields such as orthopedic implants.Herein,a fine-grain structure consisting of weak anodic nano-lamellar solute-enriched stacking faults(SESFs)with the average thickness of 8 nm and spacing of 16 nm is constructed in an as-extruded Mg96.9Y1.2Ho1.2Zn0.6Zr0.1(at.%)alloy,obtaining a high yield strength(YS)of 370 MPa,an excellent elongation(EL)of 17%,and a low corrosion rate of 0.30 mm y−1(close to that of high-pure Mg)in a uniform corrosion mode.Through scanning Kelvin probe force microscopy(SKPFM),one-dimensional nanostructured SESFs are identified as the weak anode(∼24 mV)for the first time.The excellent corrosion resistance is mainly related to the weak anodic nature of SESFs and their nano-lamellar structure,leading to the more uniform potential distribution to weaken galvanic corrosion and the release of abundant Y^(3+)/Ho^(3+)from SESFs to form a more protective film with an outer Ca_(10)(PO_(4))_(6)(OH)_(2)/Y_(2)O_(3)/Ho_(2)O_(3) layer(thickness percentage of this layer:72.45%).For comparison,the as-cast alloy containing block 18R long period stacking ordered(LPSO)phase and the heat-treated alloy with fine lamellar 18R-LPSO phase(thickness:80 nm,spacing:120 nm)are also studied,and the characteristics of SESFs and 18R-LPSO phase,such as the weak anode nature of the former and the cathode nature of the latter(37-90 mV),are distinguished under the same alloy composition.Ultimately,we put forward the idea of designing Mg alloys with high mechanical and anti-corrosion properties by constructing"homogeneous potential strengthening microstructure",such as the weak anode nano-lamellar SESFs structure.
文摘Mg and its alloys have been introduced as promising biodegradable materials for biomedical implant applications due to their excellent biocompatibility, mechanical behavior, and biodegradability. However, their susceptibility to rapid corrosion within the body poses a significant challenge and restricts their applications. To overcome this issue, various surface modification techniques have been developed to enhance the corrosion resistance and bioactivity of Mg-based implants. PEO is a potent technique for producing an oxide film on a surface that significantly minimizes the tendency to corrode. However, the inevitable defects due to discharges and poor biological activity during the coating process remain a concern. Therefore, adding suitable particles during the coating process is a suitable solution. Hydroxyapatite(HAp)has attracted much attention in the development of biomedical applications in the scientific community. HAp shows excellent biocompatibility due to its similarity in chemical composition to the mineral portion of bone. Therefore, its combination with Mg-based implants through PEO has shown significant improvements in their corrosion resistance and bioactivity. This review paper provides a comprehensive overview of the recent advances in the preparation, characterization, corrosion behavior and bioactivity applications of HAp particles on Mg-based implants by PEO.
基金supported by the National Natural Science Foundation of China(Grant No.51975151)the Heilongjiang Provincial Natural Science Foundation of China(Grant No.LH2019E041)the Heilongjiang Touyan Team.
文摘Biomimetic bone-active coatings composed of inorganic nano-hydroxyapatite(i.e.,nHA)and organic silk fibroin(i.e.,SF)are layer-by-layer deposited on Mg-Zn-Ca alloy by a controllable ultrasonic spray method.Meanwhile,plasma activation is developed as a promising strategy to pretreat magnesium surfaces,which facilitates the direct adhesion of coatings with enhanced bonding interfaces.In this work,we engineer the nHA/SF composite coatings with excellent mechanical properties and adhesion force.The optimized parameters of ultrasonic spray bring significant influence on the surface morphologies of coatings.Assisted by hybrid plasma of oxygen and nitrogen(i.e.,O_(2)/N_(2) plasma),the activated Mg-Zn-Ca surfaces are uniformly covered by a robust and compact nHA/SF composite coating,establishing a multifunctional system with superior corrosion resistance and biological performance.Interestingly,secondary oxygen plasma treatment of nHA/SF coatings(A-nHA/SF)promotes the hydrophilicity,leading to a rapid self-repair effect from surface damage.The improvement of anti-corrosion and self-repair provides a dependable platform for better cell adhesion,proliferation,spreading and differentiation.These favorable factors contribute to the preferable in vivo biocompatibility and the promotion of newly formed bones for the A-nHA/SF-coated Mg implants.This study lays important foundations for coating strategy on biomedical magnesium alloy as multifunctional osteogenic system in bioactive implantable applications.
文摘Immune adjuvants are immune modulators that have been developed in the context of infectious vaccinations.There is currently a growing interest in immune adjuvants due to the development of immunotherapy against cancers.Immune adjuvant mechanisms of action are focused on the initiation and amplification of the inflammatory response leading to the innate immune response,followed by the adaptive immune response.The main activity lies in the support of antigen presentation and the maturation and functions of dendritic cells.Most immune adjuvants are associated with a vaccine or incorporated into the new generation of m RNA vaccines.Few immune adjuvants are used as drugs.Hydroxyapatite(HA)ceramics and azoximer bromide(AZB)are overlooked molecules that were used in early clinical trials,which demonstrated clinical efficacy and excellent tolerance profiles.HA combined in an autologous vaccine was previously developed in the veterinary field for use in canine spontaneous lymphomas.AZB,an original immune modulator derived from a class of heterochain aliphatic polyamines that is licensed in Russia,the Commonwealth of Independent States,and Slovakia for infectious and inflammatory diseases,is and now being developed for use in cancer with promising results.These two immune adjuvants can be combined in various immunotherapy strategies.
文摘Cancerous diseases and diseases resulting from bacteria and fungi are some of the pressures that humans face.Therefore,the development of biomaterials that are resistant to cancerous diseases,bacteria,and fungi has become one of the requirements of the medical field to extend the life of the biomaterial and fight pathogens after implanting these materials inside the human body.One of the important biomaterials used in the field of orthopedics is hydroxyapatite.In this research,Nano substituted hydroxyapatite was prepared by the wet precipitation method,including replacing 5%of the calcium ions with neodymium,cerium,magnesium,and zinc ions in cationic substitution.Many tests were carried out to characterize the prepared material.The biological properties were evaluated by examining the resistance of the substituted hydroxyapatite to bacteria and fungi,in addition to testing the effect of the material on normal cells and bone cancer cells.The results showed a new structure of hydroxyapatite after the substitution process and a significant improvement in the biological properties of the prepared biomaterial compared to other researches.
基金Thisworkwas supported by the Shanghai Science and Technology Committee(No.22dz1204700)the NationalKeyR&D Program of China(Nos.2020YFA0803800 and 2017YFE0132200)+2 种基金the National Natural Science Foundation of China(Nos.82072510,21907034,21788102,21525417,and 51620105009)the Natural Science Foundation of Guangdong Province(Nos.2019B030301003 and 2016A030312002)the Innovation and Technology Commission of Hong Kong(No.ITC-CNERC14S01).
文摘Existing technologies used to detect monosodium urate(MSU)crystals for gout diagnosis are not ideal due to their low sensitivity and complexity of operation.The purpose of this study was to explore whether aggregation-induced emission luminogens(AIEgens)can be used for highly specific imaging of MSU crystals to assist in the diagnosis of gout.First,we developed a series of luminogens(i.e.,tetraphenyl ethylene(TPE)-NH_(2),TPE-2NH_(2),TPE-4NH_(2),TPE-COOH,TPE-2COOH,TPE-4COOH,and TPE-Ketoalkyne),each of which was then evenly mixed with MSU crystals.Next,optimal fluorescence imaging of each of the luminogens was characterized by a confocal laser scanning microscope(CLSM).This approach was used for imaging standard samples of MSU,hydroxyapatite(HAP)crystals,and mixed samples with 1:1 mass ratio of MSU/HAP.We also imaged samples from mouse models of acute gouty arthritis,HAP deposition disease,and comorbidities of interest.Subsequently,CLSM imaging results were compared with those of compensated polarized light microscopy,and we assessed the biosafety of TPE-Ketoalkyne in the RAW264.7 cell line.Finally,CLSM time series and three-dimensional imaging were performed on MSU crystal samples from human gouty synovial fluid and tophi.As a promising candidate for MSU crystal labeling,TPE-Ketoalkyne was found to detect MSU crystals accurately and rapidly in standard samples,animal samples,and human samples,and could precisely distinguish gout from HAP deposition disease.This work demonstrates that TPE-Ketoalkyne is suitable for highly specific and timely imaging of MSU crystals in gouty arthritis and may facilitate future research on MSU crystal-related diseases.
文摘Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commercial temperature controlled microwave chemistry ovens (TCMC), digesters, and axial field helical antennae. For each of these microwave applicators the process energy budget where estimated (Watts multiplied by process time = kJ) and energy density (applied energy divided by suspension volume = kJ·ml<sup>-1</sup>) range between 180 ± 176.8 kJ, and 79.5 ± 79 kJ·ml<sup>-1</sup>, respectively. The axial field helical field an-tenna applicator is found to be the most energy efficient (0.253 kJ·m<sup>-1</sup> per kJ, at 36 W). Followed by microwave ovens (4.47 ± 3.9 kJ·ml<sup>-1</sup> per 76.83 ± 39 kJ), and TCMC ovens (2.86 ± 2.3 kJ·m<sup>-1</sup> per 343 ± 321.5 kJ). The digester applicators have the least energy efficiency (36.2 ± 50.7 kJ·m<sup>-1</sup> per 1010 ± 620 kJ). A comparison with reconstructed ‘non-thermal’ microwave oven inactivation microorganism experiments yields a power-law signature of n = 0.846 (R<sup>2</sup> = 0.7923) four orders of magnitude. The paper provides a discussion on the Au and Ag nanoparticle chemistry and bio-chemistry synthesis aspects of the microwave applicator energy datasets and variation within each dataset. The visual and analytical approach within the energy phase-space projection enables a nanoparticle synthesis route to be systematically characterized, and where changes to the synthesis are to be mapped and compared directly with historical datasets. In order to help identify lower cost nanoparticle synthesis, in addition to potentially reduce synthesis energy to routes informed changes to potentially reduce synthesis energy budget, along with nanoparticle morphology and yield.
