Corrosion and in vitro cytocompatibility investigation on the designed Mg-Zn-Ag metallic glasses for biomedical application

In the present work,seven Mg-Zn-Ag alloys with the nominal composition of Mg_(96-x)Zn_(x)Ag_(4)(x=17,20,23,26,29,32,35 in at.%)were prepared by induction melting and single-roller melt-spinning.The X-ray diffraction(XRD)analyses indicate the metallic glasses with three composition of Mg_(73)Zn_(23)Ag_(4),Mg_(70)Zn_(26)Ag_(4),and Mg_(67)Zn_(29)Ag_(4)were obtained successfully.The differential scanning calorimetry(DSC)measurement was used to obtain the characteristic temperature of Mg-Zn-Ag metallic glasses for the glass-forming ability analysis.The maximum glass transition temperature(Trg)was found to be 0.525 with a composition close to Mg_(67)Zn_(29)Ag_(4),which results in the best glass-forming ability.Moreover,the immersion test in simulated body fluid(SBF)demonstrate the relative homogeneous corrosion behavior of the Mg-Zn-Ag metallic glasses.The corrosion rate of Mg-Zn-Ag metallic glasses in SBF solution decreases with the increase of Zn content.The sample Mg_(67)Zn_(29)Ag_(4)has the lowest corrosion rate of 0.19mm/yr,which could meet the clinical application requirement well.The in vitro cell experiments show that the Madin-Darby canine kidney(MDCK)cells cultured in sample Mg_(67)Zn_(29)Ag_(4)and its extraction medium have higher activity.However,the Mg-Zn-Ag metallic glasses exhibit obvious inhibitory effect on human rhabdomyosarcoma(RD)tumor cells.The present investigations on the glass-forming ability,corrosion behavior,cytocompatibility and tumor inhibition function of the Mg-Zn-Ag based metallic glass could reveal their biomedical application possibility.

Cytocompatibility with osteogenic cells and enhanced in vivo anti-infection potential of quaternized chitosan-loaded titania nanotubes

Infection is one of the major causes of failure of orthopedic implants. Our previous study demonstrated that nanotube modification of the implant surface, together with nanotubes loaded with quaternized chitosan （hydroxypropyltrimethyl ammonium chloride chitosan, HACC）, could effectively inhibit bacterial adherence and biofilm formation in vitro. Therefore, the aim of this study was to further investigate the in vitro cytocompatibility with osteogenic cells and the in vivo anti-infection activity of titanium implants with HACC-loaded nanotubes （NT-H）. The titanium implant （Ti）, nanotubes without polymer loading （NT）, and nanotubes loaded with chitosan （NT-C） were fabricated and served as controls. Firstly, we evaluated the cytocompatibility of these specimens with human bone marrow-derived mesenchymal stem cells in vitro. The observation of cell attachment, proliferation, spreading, and viability in vitro showed that NT-H has improved osteogenic activity compared with Ti and NT-C. A prophylaxis rat model with implantation in the femoral medullary cavity and inoculation with methiciUin-resistant Staphylococcus aureus was established and evaluated by radiographical, microbiological, and histopathological assessments. Our in vivo study demonstrated that NT-H coatings exhibited significant anti-infection capability compared with the Ti and NT-C groups. In conclusion, HACC-loaded nanotubes fabricated on a titanium substrate show good compatibility with osteogenic cells and enhanced anti-infection ability in vivo, providing a good foundation for clinical application to combat orthopedic implant-associated infections.

Superhydrophobic fluoride conversion coating on bioresorbable magnesium alloy——fabrication,characterization,degradation and cytocompatibility with BMSCs

A micro-nano structure CaF_(2)chemical conversion layer was prepared on fluoride-treated AZ31 alloy,then the composite fluoride conversion film(CaF_(2)/MgF_(2))was modified by stearic acid(SA)and fabricated a superhydrophobic surface.The fluoride-treated magnesium,fluoride conversion film and superhydrophobic coating were characterized by SEM,EDS,XRD and FTIR.The properties of coatings1 adhesion and corrosion resistance were evaluated via tape test and electrochemical measurement.The cytocompatibility of the MgF_(2),CaF_(2)and superhydrophobic CaF_(2)/SA surface was investigated with bone marrow-derived mesenchymal stem cells(BMSCs)by direct culture for 24 h.The results showed that the superhydrophobic fluoride conversion coating composed of inner MgF_(2)layer and the outer CaF_(2)/SA composite layer had an average water contact angle of 152°.SA infiltrated into the micro-nano structure CaF_(2)layer and formed a strong adhesion with CaF_(2)layer.Furthermore,the super-hydrophobic coating showed higher barrier properties and corrosion resistance compared with the fluoride conversion film and fluoride-treated AZ31 alloy.The BMSC adhesion test results demonstrated MgF_(2)CaF_(2)and CaF_(2)/SA coatings were all nontoxic to BMSC.At the condition of in direct contact with cells,MgF_(2)showed higher cell density and enhanced the BMSCs proliferation,while CaF_(2)and CaF_(2)/SA coating showed no statistically difference in cell density compared with glass reference but the CaF_(2)and CaF_(2)/SA coating were not conducive to BMSCs adhesion.

In vitro evaluation of degradation,cytocompatibility and antibacterial property of polycaprolactone/hydroxyapatite composite coating on bioresorbable magnesium alloy

Polycaprolactone/hydroxyapatite(PCL/HA)composite coating was fabricated by a combination of hydrothermal and dipping methods to delay the degradation of Mg alloy AZ31 as bioresorbable materials.The PCL/HA coating was composed of nano rod-shape HA crystals and PCL filled in the space of HA crystals.Compared with the single HA coating,the binding strength between the PCL/HA composite coating and Mg alloy was obviously improved and the PCL/HA coating still adhered to the surface of AZ31 substrate even after 38 days of immersion.The electrochemical corrosion rate of HA coated sample was reduced by ten times after being filled by PCL.The electrochemical impedance spectroscopy(EIS)and immersion test results showed that the PCL/HA composite coating could provide a more effective barrier for Mg substrate than the HA coating alone.The cytocompatibility and the antibacterial property of HA coating and PCL/HA coating were evaluated by culturing with bone marrow-derived mesenchymal stem cells(BMSCs)and methicillin-resistant staphylococcus aureus(MRSA)for 24 h under direct culture conditions,respectively.The PCL/HA composite coating showed better BMSC cell compatibility,more suitable for BMSC adhesion than HA coating alone and showed a potential application prospect as a biological materials.However,from the perspective of clinical applications,the antibacterial property of PCL/HA composite coating needs to be further improved.

Promoted Cytocompatibility of Silk Fibroin Fiber Vascular Graft through Chemical Grafting with Bioactive Molecules

Natural silk from Bombyx mori has been used as medical sutures for several decades,and regenerated silk fibroin( RSF)based biomaterials have been increasingly studied in the past thirty years. However,vascular graft derived from silk fibroin fiber has been explored in recent several years with development of textile science and engineering. Moreover,endothelialization of vascular graft has been seen as an ideal strategy for preventing thrombosis and getting higher patency in a long term. Therefore,in the present work silk fibroin fiber vascular graft( SF) was chemically grafted with bioactive molecules such as heparin and RSF to improve the cytocompatibility. 3-aminopropyl-triethoxysilane(APTES),1-ethyl-3-(3-dimethylaminopropyl) carbodiie hydrochlide( EDC · HCl),and N-hydroxysuccinimide( NHS) have been employed as coupling agent and crosslinking agents,respectively. Microscopy and ATRFTIR were used to characterize the surface changes and the structure of the grafts after treatment,respectively. Cell culture in vitro and MTT assay were conducted to determine the improvement of cell affinity to the graft. Furthermore,mechanical properties of the grafts before and after treatment were compared. The results showed that the chemical grafting was an effective method for improving the cytocompatibility of SF without significant loss of mechanical properties.

Preparation,Rheological Properties and Primary Cytocompatibility of TPU/PLA Blends as Biomedical Materials

A polymer blends containing thermoplastic polyurethane（TPU） and poly（lactic acid）（PLA） as a biomedical material were prepared by a process of modifying thermally induced phase separation（MTIPS） and melt blending.The influences of composition,shear frequency,and temperature on the rheological behaviors of the blends were investigated by small amplitude oscillatory shear rheology.The results revealed that the addition of TPU into PLA significantly decreased the non-Newtonian index of the blends,and increased the sensitivity of the blends on shear rate,suggesting that optimization of the shear rate and temperature could improve the flowability of the blend melts in the extrusion process.In addition,the results of SEM images revealed that TPU distributed well into PLA matrix and showed good compatibility between the TPU and PLA,which made the blends with good toughness.The primary cytocompatibility of the blends was evaluated using C2C12 cells.The results suggested that the TPU/PLA blends did not affect cell growth,showing no cytotoxicity.In short,the TPU/PLA blends with excellent toughness had potential application as biomedical devices.

Preparation of Silk Fibroin Microspheres and Its Cytocompatibility

The goal of this proof-of-concept study was the fabrication of porous silk fibroin (SF) microspheres which could be used as cell culture carriers under very mild processing conditions. The SF solution was differentiated into droplets which were induced by a syringe needle in the high-voltage electrostatic field. They were collected and frozen in liquid nitrogen and water in droplets formed ice crystals which sublimated during lyophilization and a great quantity of micropores shaped in SF microspheres. Finally, the microspheres were treated in ethanol so as to transfer the molecular conformation into β-sheet and then they were insoluble in water. SF particles were spherical in shape with diameters in the range of 208.4 μm to 727.3 μm, while the pore size on the surface altered from 0.3 μm to 10.7 μm. In vitro, the performances of SF microspheres were assessed by culturing L-929 fibroblasts cells. Cells were observed to be tightly adhered and fully extended;also a large number of connections were established between cells. After 5-day culture, it could be observed under a confocal laser scanning microscope that the porous microenvironment offered by SF particles accelerated proliferation of cells significantly. Furthermore, porous SF particles with smaller diameters (200 - 300 μm) might promote cell growth better. These new porous SF microspheres hold a great potential for cell culture carriers and issue engineering scaffolds.

Polyurethane/poly(vinyl alcohol) hydrogel coating improves the cytocompatibility of neural electrodes

Neural electrodes,the core component of neural prostheses,are usually encapsulated in polydimethylsiloxane（PDMS）.However,PDMS can generate a tissue response after implantation.Based on the physicochemical properties and excellent biocompatibility of polyurethane（PU）and poly（vinyl alcohol）（PVA）when used as coating materials,we synthesized PU/PVA hydrogel coatings and coated the surface of PDMS using plasma treatment,and the cytocompatibility to rat pheochromocytoma（PC12）cells was assessed.Protein adsorption tests indicated that the amount of protein adsorption onto the PDMS substrate was reduced by 92%after coating with the hydrogel.Moreover,the PC12 cells on the PU/PVA-coated PDMS showed higher cell density and longer and more numerous neurites than those on the uncoated PDMS.These results indicate that the PU/PVA hydrogel is cytocompatible and a promising coating material for neural electrodes to improve their biocompatibility.

Cytocompatibility of Self-assembled Hydrogel from IKVAV-containing Peptide Amphiphile with Neural Stem Cells

Neural Stem Cells （NSCs） were incubated with self-assembled hydrogel from IKVAV-containing peptide amphiphile （IKVAV-PA） for one week. The cytocompatibility of hydrogel was evaluated. NSCs were seeded in three-dimensional （3D） hydrogels （Experimental Group, EG） or surface of coverslips （Control Group, CG）, double-labeled with Calcein-AM and PI. A growth curve of cells was obtained according to CCK-8. TEM study of hydrogel revealed a network of nanofibers. NSCs began to proliferate after 24 h of incubation, and formed bigger neurospheres at 48 h in EG than in CG. Cell proliferation activity was higher in EG than in CG （P〈0.05）. The self-assembled Hydrogel had good cytocompatibility and promoted the proliferation of NSCs.

Surface Modification of Polyglycolic Acid Fibers by Hydrogen Peroxide for Enhancing Hydrophilicity and Cytocompatibility

Hydrogen peroxide( H_2O_2) is applied for surface modification of polyglycolic acid( PGA) fibers in order to enhance the hydrophilicity and cytocompatibility of PGA fibers effectively,and maintain the breaking strength as the same time. PGA fibers are dipped in H_2O_2 solution a certain time for modification. Scanning electron microscopy( SEM) was used to observe the surface morphology of PGA fibers before and after modification. The varying of PGA macromolecule was examined with Fourier transform infrared spectroscopy( FTIR) analyses. X-ray diffraction( XRD) and differential scanning calorimetry( DSC) analysis showed that crystallinity slightly decreases. Mechanical performance test showed tensile force of modified PGA fiber was increased. The water contact angle test indicated the improving of hydrophilic. A cell proliferation assay showed that fibroblast cells attach and proliferate well on the fibers, which meant the modified fibers possess good cytocompatibility. These results suggest that H_2O_2 surface modification is easy to operate and a advantageous modification method for PGA fibers.

The Cytocompatibility of Genipin-Crosslinked Silk Fibroin Films

There is an increasing demand for crosslinking methods of silk fibroin (SF) scaffolds in biomedical applications that could maintain the biocompatibility, bioactivity as well as improve the water resistance and mechanical properties of SF materials. In this study, SF was crosslinked effectively with genipin which is a naturally occurring iridoid glucoside and the crosslinking mechanism was investigated through FTIR and amino acid analysis. The results showed that genipin could react with the -NH2 groups on the side chains of SF macromolecules and to form inter- and intra-molecular covalent bonds, and improved the stability of SF materials significantly. In vitro, the performances of genipin-crosslinked SF films were assessed by seeding L929 cells and compared with ethanol-processed SF films, glutaraldehyde and polyethylene glycol diglycidyl ether crosslinked ones. The genipin-crosslinked SF films showed a similar affinity to cells as ethanol-processed ones, and a higher bioactivity in promoting cell growth and proliferation, inhibition of cell apoptosis, and maintenance of normal cell cycle compared with glutaraldehyde and polyethylene glycol diglycidyl ether crosslinked SF films. These features, combined with the decrease of brittleness of SF films crosslinked with chemical methods, substantiated genipin as an effective and biocompatible agent for the manufacturing of bioactive SF materials which used as tissue engineering scaffolds and drug delivery carriers.

Antibacterial ability and cytocompatibility of Cu-incorporated Ni–Ti–O nanopores on NiTi alloy

Nearly equiatomic nickel–titanium(NiTi) alloy is an ideal implant biomaterial because of its shape memory effect, superelasticity, low elastic modulus as well as other desirable properties.However, it is prone to infection because of its poor antibacterial ability.The present work incorporated Cu into Ni–Ti–O nanopores(NP–Cu) anodically grown on the NiTi alloy to enhance its antibacterial ability, which was realized through electrodeposition.Our results show that incorporation of Cu(0.78 at%–2.37 at%)has little influence on the NP diameter, length and morphology.The release level of Cu ions is in line with loadage which may be responsible for the improved antibacterial ability of the NiTi alloy to combat possible bacterial infection in vivo.Meanwhile, the NP–Cu shows better cytocompatibility and even can promote proliferation of bone marrow mesenchymal stem cells(BMSCs),up-regulate collagen secretion and extracellular matrix mineralization when compared with Cu-free sample.Better antibacterial ability and cytocompatibility of the NP–Cu render them to be promising when serving as NiTi implant coatings.

In vitro degradation and cytocompatibility of a low temperature in-situ grown self-healing Mg-Al LDH coating on MAO-coated magnesium alloy AZ31

Basically,Mg–Al layered double hydroxide(LDH)coatings are prepared on the surface of micro-arc oxidation(MAO)coated magnesium(Mg)alloys at a high temperature or a low pH value.This scenario leads to the growth rate of LDH coating inferior to the dissolution rate of the MAO coating.This in turn results in limited corrosion resistance of the composite coating.In this study,a Mg–Al LDH coating on MAO-coated Mg alloy AZ31 is prepared through a water bath with a higher pH(13.76)at a lower temperature(60℃).FE-SEM,EDS,XRD,XPS,and FT-IR are applied to analyze the surface morphology,chemical compositions,and growth process.Electrochemical polarization,electrochemical impedance spectroscopy(EIS)and hydrogen evolution tests are employed to evaluate the corrosion resistance of the samples.The results disclose that the MAO coating is completely covered by the nanosheet-structured LDH coating with a thickness of approximately 3.8μm.The corrosion current density of the MAO-LDH composite coating is decreased four orders of magnitude in comparison to its substrate;the presence of a wide passivation region in anodic polarization branch demonstrates its strong self-healing ability,indicating the hybrid coating possesses excellent corrosion resistance.The formation mechanism of the LDH coating on the MAO-coated Mg alloy is proposed.Furthermore,the cytocompatibility is assessed via an indirect extraction test for MC3T3-E1 pre-osteoblasts,which indicates an acceptable cytocompatibility of osteoblasts for the composite coating.

Cytocompatibility and Hemolysis of AZ31B Magnesium Alloy with Si-containing Coating

In the present study, a Si-containing coating was fabricated on AZ31B Mg alloy. Cytocompatibility of the coated alloy was evaluated by both indirect and direct contact methods, respectively. Effects of a number of incubation variables on the sensitivity and reproducibility of the hemolysis test were also examined by using positively and negatively responding biomaterials. Cytocompatibility testing results indicated that cell condition, cell adherence, cell proliferation and extracellular matrix secretion of the coated alloy were improved compared with those of the uncoated alloy for different extraction and co-culture time. The hemolysis test suggested that hemolysis testing conditions were critical to determine the hemolysis of the alloy. It was also found that 1 day in vitro degradation of the uncoated AZ31B alloy had no destructive effect on erythrocyte. As for the coated AZ31B alloy at any time point, the hemolysis rate was much lower than 5%, the safe value for biomaterials. These in vitro experimental results indicate that the Si-containing coating is effective to improve the cytocompatibility and hemolysis behaviors of AZ31B alloy during its degradation.

Effect of Alloyed Mo on Mechanical Properties,Biocorrosion and Cytocompatibility of As-Cast Mg-Zn-Y-Mn Alloys

The influences of Mo contents on mechanical properties,biocorrosion and cytocompatibility of as-cast Mg-6Zn-8.16Y-2.02Mn-xMo(x=0.0,0.1,0.3,0.5,0.7 wt%) alloys were firstly investigated.Appropriate amount of Mo was conducive to grain refinement and the formation of long-period stacking ordered structure with continuous distribution,which was advantageous to mechanical properties and corrosion resistance.Mg-6Zn-8.16Y-2.02Mn-0.3Mo exhibited the ultimate tensile strength of 265.0 MPa,elongation of 13.5% and the lowest weight loss rate in Hank’s solution.Moreover,the cell toxicity cultured in 25% extract was evaluated and the alloy with 0.3 wt% Mo exhibited the best cytocompatibility.Thus,the alloy was expected to become a novel biodegradable implant material.

3D Printed Gelatin Scaffold with Improved Shape Fidelity and Cytocompatibility by Using Antheraea pernyi Silk Fibroin Nanofibers

Gelatin(G)is a commonly used natural biomaterial owing to its good biocompatibility and easy availability.However,using pure gelatin as a bioink can barely achieve an ideal shape fidelity in 3D printing.In this study,Antheraea pernyi silk fibroin nanofibers(ASFNFs)with arginine-glycine-aspartic acid(RGD)peptide and partial natural silk structure are extracted and combined with pure gelatin bioink to simultaneously improve the shape fidelity and cytocompatibility of corresponding 3D printed scaffold.Results show that the optimum printing temperature is 30℃ for these bioinks.The printed filaments using 16G/4ASFNFs bioink(16wt%gelatin and 4wt%ASFNFs)demonstrate better morphology and larger pore size than those printed by pure gelatin bioink(20G,20wt%gelatin),thus successfully improve the shape fidelity and porosity of the 3D printed scaffold.The 16G/4ASFNFs scaffold also demonstrate higher swelling ratio and faster degradation rate than the pure gelatin scaffold.Moreover,the cell viability and proliferation ability of Schwann cells cultured on the 16G/4ASFNFs scaffold are significantly superior than those cultured on the pure 20G scaffold.The ASFNFs enhanced 16G/4ASFNFs scaffold reported here are expected to be a candidate with excellent potential for biomedical applications.

In vitro cytocompatibility evaluation of poly(octamethylene citrate) monomers toward their use in orthopedic regenerative engineering

Citrate based polymer poly(octamethylene citrate)(POC)has shown promise when formulated into composite material containing up to 65 wt%hydroxylapatite(HA)for orthopedic applications.Despite significant research into POC,insufficient information about the biocompatibility of the monomers 1,8-Octanediol and Citrate used in its synthesis is available.Herein,we investigated the acute cytotoxicity,immune response,and long-term functionality of both monomers.Our results showed a cell-type dependent cytotoxicity of the two monomers:1,8-Octanediol induced less acute toxicity to 3T3 fibroblasts than Citrate while presenting comparable cytotoxicity to MG63 osteoblast-like cells;however,Citrate demonstrated enhanced compatibility with hMSCs compared to 1,8-Octanediol.The critical cytotoxic concentration values EC30 and EC50,standard for comparing cytotoxicity of chemicals,were also provided.Additionally,Citrate showed slower and less inhibitory effects on long-term hMSC cell proliferation compared with 1,8-Octanediol.Furthermore,osteogenic differentiation of hMSCs exposure to Citrate resulted in less inhibitory effect on alkaline phosphatase(ALP)production.Neither monomer triggered undesired pro-inflammatory responses.In combination with diffusion model analysis of monomer release from cylindrical implants,based on which the maximum concentration of monomers in contact with bone tissue was estimated to be 2.2
104 mmol/L,far lower than the critical cytotoxic concentrations as well as the 1,8-Octanediol concentration(0.4 mg/mL or 2.7 mmol/L)affecting hMSCs differentiation,we provide strong evidence for the cytocompatibility of the two monomers degraded from citrate-based composites in the orthopedic setting.

Corrosion behavior and cytocompatibility of fluoride-incorporated plasma electrolytic oxidation coating on biodegradable AZ31 alloy

Fluoride-incorporated plasma electrolytic oxidation(PEO)coating was fabricated on biodegradable AZ31 alloy.The surface morphologies and phases were investigated by scanning electron microscopy and X-ray diffraction.The effect of fluoride incorporation in coatings on corrosion behaviour was investigated in simulated body fluid and in vitro cytocompatibility of the coatings was also studied by evaluating cytotoxicity,adhesion,proliferation and live-dead stain of osteoblast cells(MC3T3-E1).Furthermore,the corrosion morphologies in vivo were examined.The results showed that the fluoride could be incorporated into the coating to form MgF2 phase.In vitro and in vivo degradation tests revealed that the corrosion resistance of the coating could be improved by the incorporation of fluoride,which may attribute to the chemical stability of MgF2 phase.Moreover,good cytocompatibility of fluoride-incorporated coating was confirmed with no obvious cytotoxicity,enhanced cell adhesion and proliferation.However,when the fluoride content was high,a slight inhibition of cell growth was observed.The results indicate that although fluoride incorporation can enhance the corrosion resistance of the coatings,thus resulting a more suitable environment for cells,the high content of fluoride in the coating also kill cells ascribed to the high released of fluorine.If the content of fluoride is well controlled,the PEO coating with MgF2 phase is a promising surface modification of Mg alloys.

Biogenic synthesis of silver nanoparticles using Persicaria odorata leaf extract: Antibacterial, cytocompatibility, and in vitro wound healing evaluation

Biogenic synthesis of silver nanoparticles(b-AgNPs)utilising plant extract has gained the interest of researchers due to the environmentally friendly and cost-effective technique.However,the extent of its application in the biomedical field remains scarce.This study evaluates the antibacterial,cytocompatibility,and wound healing activities of synthesised AgNPs using Persicaria odorata leaves extract(PO-AgNPs).The formation of PO-AgNPs was observed by visual colour changes and verified by ultraviolet-visible(UV–vis)spectrophotometer,which revealed a surface plasmon resonance(SPR)at around 440 nm,and further confirmed by X-ray diffraction(XRD).Characterisation using Fourier transform infrared(FTIR)spectroscopy showed biomolecules from the leaves extract presented together on PO-AgNPs.Field emission scanning electron microscope(FESEM)and high-resolution transmission electron microscopy(HR-TEM)images revealed PO-AgNPs nanospheres with diameters of 11±3 nm.Disc diffusion test(DDT)and minimum inhibitory concentration(MIC)analysis resulted in a dose-dependent inhibition of PO-AgNPs against tested Staphylococcus epidermidis and Methicillin-resistant Staphylococcus aureus(MRSA).These results were further corroborated by time-kill kinetic assay which revealed that PO-AgNPs were bactericidal against both strains 24 h post-treatment.Cytocompatibility and in vitro wound healing evaluation against normal human fibroblast cells,HSF 1184 inferred that PO-AgNPs are non-toxic to normal cells and able to enhance cell migration as compared to the non-treated cells.Therefore,PO-AgNPs are biocompatible and possess antibacterial and wound healing capabilities that are useful in biomedical applications.

BSA-lysozyme coated NaCa_(2)HSi_(3)O_(9)nanorods on titanium for cytocompatibility and antibacterial activity

Extracellular supplement of Ca and Si accelerates osteogenisis and angiogenisis during bone repair.CaSi-based ceramics are biodegradable and can release Ca and Si ions efficiently.However,locally high alkalinity induced by excessively rapid degradation limits their application.In this paper,NaCa_(2)HSi_(3)O_(9)(NCS)nanorods were fabricated on Ti by micro-arc oxidation and hydrothermal treatment;protein layers consisted of different rations of bovine serum albumin(BSA)and lysozyme(LYS)were prepared on NCS nanorods by spinning coating and thermal stabilization.The microstructure,ion releasing and wettability of coatings were observed;osteoblast and endotheliocyte behaviors,as well as bacteria response in vitro,were evaluated.The protein layer did not change microstructure and phase composition of nanorods but acted as a barrier isolating nanorods from contacting medium,and it results in slowing down the degradation of nanorods.The reduced increase of pH value,released Ca and Si ions and incorporation of LYS in BSA protein layer gave NCS nanorods improved MC3 T3-E1 and HUVECs response,compared with Ti.Meanwhile,the protein layers except pure LYS endowed nanorods with a highly antibacterial effect against staphylococcus aureus and escherichia coli simultaneously,indicating the key role of BSA in resisting antibacterial adhesion.NCS nanorods with BSA and LYS composited protein layers should be a potential coating applied on Ti implants for increasing osseointegration.