Ke Duan

Southwest Jiaotong University, Hua-yang, Sichuan, China

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Publications (25)56.09 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The titanium percutaneous implants were widely used in clinic; however, they have an increased risk of infection since they breach the skin barrier. Lack of complete skin integration with the implants can cause infection and implant removal. In this work, three titania nanotubes (TNT) with different diameters, 50 nm (TNT-50), 100 nm (TNT-100) and 150 nm (TNT-150) arrays were prepared on titanium surfaces by anodization, pure titanium (pTi) was used as control. Samples were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle analysis. The antibacterial efficiency of TNT was evaluated in vitro against Staphylococcus aureus under the visible light. The results indicated that TNT-100 had the highest antibacterial efficiency under the visible light. Subsequently, TNT implants and pTi implants were placed subcutaneously to the dorsum of New Zealand White rabbits, 108 CFU S. aureus was inoculated into the implant sites 4 h after surgery. The TNF-alpha and IL-1alpha were determined using enzyme linked immunoassay (ELISA). TNT implants revealed less inflammatory factor release than pTi implants with or without injected S. aureus liquid. According to the histological results, the TNT implants displayed excellent tissue integration. Whereas, pTi implants were surrounded with fibrotic capsule, and the skin tissue was almost separated from the implant surface. Therefore, the TNT significantly inhibited the infection risk and enhanced tissue integration of the percutaneous implants compared to pTi. The immersion test in the culture medium suggested that one of causes be probably more proteins adsorbed on TNT than on pTi.
    Applied Surface Science 07/2015; 344. DOI:10.1016/j.apsusc.2015.03.115 · 2.54 Impact Factor
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    ABSTRACT: Nanostructured hollow hydroxyapatite (HA) particles were fabricated under hydrothermal conditions with cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (H6L) as the template, and their formation process was investigated. Without the assistance of H6L, the product consisted of ribbon-like HA crystals. With the introduction of H6L, the HA particles gradually changed from flower-like plate aggregates to microspheres. Nanostructured hollow HA particles were synthesized at 50 mM H6L. Based on transmission electron microscopy and infrared spectroscopy, a possible mechanism for the formation of hollow HA particles was suggested. Differences in HA microstructure resulted in significantly different protein adsorption patterns for bovine serum albumin and lysozyme, suggesting the influence of particle microstructure on adsorption properties. The method provides a simple and controllable route to synthesize HA with various hierarchical structures.
    Journal of the European Ceramic Society 06/2015; 35(6). DOI:10.1016/j.jeurceramsoc.2014.12.028 · 2.95 Impact Factor
  • Ying Li · Jianxin Wang · Bo Feng · Ke Duan · Jie Weng
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    ABSTRACT: Antimony-doped tin oxide (ATO) nano particles were synthesized by a diffusion co-precipitation method using ethanol as a solvent in the ammonia atmosphere created by ammonium carbonate and they were annealed at 600 °C. Different doping amount of antimony and concentration of ethanol were used to investigate their effect on the conductivity and morphology of the obtained ATO powders. The results showed that the optimal experimental parameters to obtain ATO with high conductivity should be that the molar ratio of antimony and tin was 0.07:1 while the concentration of ethanol was 100%. Under these conditions, the size of the obtained nano ATO particles was in a range of 5–10 nm, their average size was 9.43 nm and their yield was nearly 80%. The highest conductivity obtained was 8 S/cm. Additionally, the reaction mechanism to form the ATO precursor was discussed in this study.
    Journal of Alloys and Compounds 06/2015; 634. DOI:10.1016/j.jallcom.2015.02.060 · 2.73 Impact Factor
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    ABSTRACT: Metallic bone implants face interfacial concerns, such as infection and insufficient bone formation. Combination of drug-loaded microparticles with the implant surface is a promising approach to reducing the concerns. The present study reports a simple method for this purpose. Drug-loaded chitosan and alginate microparticles were separately prepared by emulsion methods. Dry microparticles were introduced into porous titanium (Ti) coatings on Ti discs, and induced to agglomerate in pores by wetting with water. Agglomerates were stably entrapped in the pores: 77-82% retained in the coating after immersion in a water bath for 7 d. Discs carrying drug-loaded microparticles showed a rapid release within 6 h and a subsequent slow release up to 1 d. After coculture with Staphylococcus epidermidis for 24 h, the discs formed inhibition zones, confirming antibacterial properties. These suggest that the microparticle entrapment-based method is a promising method for reducing some of the bone-implant interfacial concerns.
    Journal of Microencapsulation 06/2015; DOI:10.3109/02652048.2015.1046515 · 1.88 Impact Factor
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    ABSTRACT: In vivo engineering of bone autografts using bioceramic scaffolds with appropriate porous structures is a potential approach to prepare autologous bone grafts for the repair of critical-sized bone defects. This study investigated the evolutionary process of osteogenesis, angiogenesis, and compressive strength of bioceramic scaffolds implanted in two non-osseous sites of dogs: the abdominal cavity and the dorsal muscle. Hydroxyapatite (HA) sphere-accumulated scaffolds (HASA) with controlled porous structures were prepared and placed in the two sites for up to 6 months. Analyses of retrieved scaffolds found that osteogenesis and angiogenesis were faster in scaffolds implanted in dorsal muscles compared with those placed in abdominal cavities. The abdominal cavity, however, can accommodate larger bone grafts with designed shape. Analyses of scaffolds implanted in abdominal cavities (an environment of a low mesenchymal stem cell density) further demonstrated that angiogenesis play critical roles during osteogenesis in the scaffolds, presumably by supplying progenitor cells and/or mesenchymal stem cells as seed cells. This study also examined the relationship between the volume of bone grafts and the physiological environment of in vivo bioreactor. These results provide basic information for the selection of appropriate implanting sites and culture time required to engineer autologous bone grafts for the clinical bone defect repair. Based on these positive results, a pilot study has applied the grafts constructed in canine abdominal cavity to repair segmental bone defect in load-bearing sites (limbs).
    Journal of Biomedical Materials Research Part A 08/2014; 102(8). DOI:10.1002/jbm.a.34919 · 3.37 Impact Factor
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    ABSTRACT: Drug release from implant surfaces is an effective approach to impart biological activities, (e.g., antimicrobial and osteogenic properties) to bone implants. Coatings of polylactide-based polymer are a candidate for this purpose, but a continuous (fully covering) coating may be non-optimal for implant-bone fixation. This study reports a simple room-temperature method for attaching poly (lactide-co-glycolide) (PLGA) microspheres to titanium (Ti) surfaces. Microspheres were prepared with polyvinyl alcohol (PVA) or polyvinylpyrrolidone (PVP) as the emulsifier. Microspheres were attached to Ti discs by pipetting as a suspension onto the surfaces followed by vacuum drying. After immersion in shaking water bath for 14 d, a substantial proportion of the microspheres remained attached to the discs. In contrast, if the vacuum-drying procedure was omitted, only a small fraction of the microspheres remained attached to the discs after immersion for only 5 min. Microspheres containing triclosan (a broad-spectrum antibiotic) were attached by porous-surfaced Ti discs. In vitro experiments showed that the microsphere-carrying discs were able to kill Staphylococcus aureus and Escherichia Coli, and support the adhesion and growth of primary rat osteoblasts. This simple method may offer a flexible technique for bone implant-based drug release.
    Applied Surface Science 08/2014; 309:112–118. DOI:10.1016/j.apsusc.2014.04.195 · 2.54 Impact Factor
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    ABSTRACT: In biomineralization, organic phases play important roles in synthesizing mineralized tissues with well controlled morphologies and structures. Inositol hexakisphosphate (IP6), a nontoxic natural polyphosphorylated carbohydrate found in mammalian cells and plant tissues, has been suggested to influence the crystallization of calcium phosphate (CaP) under ambient conditions. The present study investigated the effects of IP6 on the morphology of hydroxyapatite (HA) synthesized under hydrothermal conditions. Results showed that whisker-like HA crystals were obtained in the absence of IP6. In comparison, hollow HA microspheres consisting of nano-flakes were synthesized under the assistance of IP6. The difference indicated the impact of IP6 on the morphogenesis of HA. Transmission electron microscopy suggested that hollow microspheres were formed via a nanosphere-directed crystallization process.
    Ceramics International 08/2014; 40(7):10183-10188. DOI:10.1016/j.ceramint.2014.02.057 · 2.09 Impact Factor
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    ABSTRACT: Indium tin oxide (ITO) ceramics with high densities are difficult to achieve using conventional heating because of the volatilisation of both indium oxide and tin oxide at high temperatures. In our present study, we proposed to use a Sb2O3 doped and microwave hybrid sintering approach to prepare for ITO ceramics. The effects of the Sb2O3 content on the microstructure, densification and electrical properties of ITO ceramics were investigated. The results show that the relative density has reached 98·3% by using the hybrid sintering approach. The resistivity of the obtained ceramics showed a decrease tendency with increasing Sb2O3 content in the range of 0–1·5 wt-%. We speculate that the formation of electrons and vacancies caused by the doping of Sb2O3 and the ‘microwave effect’ might be the main reason responsible for the increase in the densification. As a result, these, in turn, further enhanced the electronic conductivity of the obtained ITO ceramics.
    Advances in Applied Ceramics 05/2014; 113(4):240-244. DOI:10.1179/1743676114Y.0000000149 · 1.11 Impact Factor
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    ABSTRACT: Titanium (Ti) and its alloys have been widely used in orthopedic and dental applications. The bonding between Ti implants and tissues is significantly important in the clinical applications, which is highly relative to the characteristics of implant surface with surface improvement by various coatings such as hydroxyapatite (HA). Meanwhile, the characteristics of modified implants surface can induce special biological response of osteogenic cells to improve the bone-implant bonding. In this paper, in order to improve Ti bioactivity and enhance its osteointegration, calcium phosphate (CaP)/titanate coatings were prepared on Ti with nanoscale surface topographies by a two-step hydrothermal process. Firstly, titanium meshes were treated in sodium hydroxide solutions at two temperatures (200 °C or 240 °C). Then, the treated meshes were immersed in calcium phosphate solutions containing various concentrations of cyclohexane-hexacarboxylic acid (H6L) under hydrothermal conditions. After this two-step process, calcium phosphate deposits, confirmed to be apatite/titanate by energy dispersive X-ray spectroscopy, were successfully formed on the treated Ti mesh surface. These results suggested that this two-step hydrothermal method can be successfully applied to fabricate robust and hierarchical nanostructured coatings of CaP/titanate on Ti implants.
    Key Engineering Materials 09/2013; 575-576:253-258. DOI:10.4028/www.scientific.net/KEM.575-576.253 · 0.19 Impact Factor
  • Journal of Inorganic Materials 08/2013; 28(8):804-810. DOI:10.3724/SP.J.1077.2013.12590 · 0.54 Impact Factor
  • Jie Huang · Shuxin Qu · Jing Wang · Dan Yang · Ke Duan · Jie Weng
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    ABSTRACT: The aim of this study is to investigate the tribological behaviors and wear mechanisms of ultra-high molecular weight polyethylene (UHMWPE) loaded with alendronate sodium (ALN), a potential drug to treat osteolysis, under different normal loads and lubrication conditions. A mixture of UHMWPE powder and ALN (1.0wt.%) solution was dried and hot pressed. The static and dynamic friction coefficients of UHMWPE-ALN were slightly higher than those of UHMWPE except under normal load as 10N and in 25v/v % calf serum. The specific wear rates of UHMWPE-ALN and UHMWPE were the lowest in 25v/v % calf serum compared to those in deionized water or physiological saline. In particular, the specific wear rate of UHMWPE-ALN was lower than that of UHMWPE at 50N in 25v/v % calf serum. The main wear mechanisms of UHMWPE and UHMWPE-ALN in deionized water and UHMWPE in physiological saline were abrasive. The main wear mechanism of UHMWPE-ALN in physiological saline was micro-fatigue. In 25v/v % calf serum, the main wear mechanism of UHMWPE and UHMWPE-ALN was abrasive wear accompanied with plastic deformation. The results of Micro-XRD indicated that the molecular deformation of UHMWPE-ALN and UHMWPE under the lower stress were in the amorphous region but in the crystalline region at the higher stress. These results showed that the wear of UHMWPE-ALN would be reduced under calf serum lubricated, which would be potentially applied to treat osteolysis.
    07/2013; 33(5):3001-9. DOI:10.1016/j.msec.2013.03.030
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    ABSTRACT: Vascularized bone grafts were constructed by implanting hydroxyapatite (HA) scaffolds with complementary macro-pore structures into the dorsal muscle of dogs. The relationship between pore structures and ectopic bone formation properties were investigated. Two types of scaffolds with complementary porous structures were fabricated by spherulite-accumulating and porogen-preparing methods, which were named as spherulite HA-positive and porogen HA-negative, respectively. After 1 month implantation, histological observation showed that all the scaffolds were encapsulated by normal muscle tissue and multiple vascular net with cells, indicating excellent biocompatibility and pore interconnectivity of the scaffolds. In the spherulite HA-positive scaffolds, a number of osteoclasts and osteoblasts coupled with new bone tissues were found after 3 and 6 months implantations, which was better than those in the porogen HA-negative scaffolds. Similarly, the improvement of mechanical properties and the reconstruction of materials in the spherulite HA-positive scaffolds were superior to those in the porogen-HA negative scaffolds. The different ectopic bone formation induced by different macro-pore structures after intramuscular implantation demonstrated the significant effect of macro-pore structures of scaffolds on osteoinduction and vascularisation.
    Acta biomaterialia 05/2013; 9(9). DOI:10.1016/j.actbio.2013.05.026 · 5.68 Impact Factor
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    ABSTRACT: The present work shows drug-carrier interactions, release behaviors and cell responses of hydroxyapatite (HA) containing salvianolic acid B (Sal B), astragalus polysaccharide (APS), and naringin. X-ray diffraction (XRD) showed that the crystallinity and crystal size of HA decreased significantly when Sal B was added (p<0.05). Transmission electron microscope (TEM) confirmed that the nano-acicular crystals of HA containing Sal B were the most fine among all specimens. It was conjectured that Sal B preferentially adsorbed on the positively charged surface of HA crystals to inhibit their growth. In vitro release of HA containing Chinese medicines followed the first-order equation. The drug-carrier affinity between HA and Sal B might have prolonged the release of Sal B. The proliferation and differentiation of osteoblasts were promoted by Chinese medicines containing HA in the time and dosage dependent manner. The osteoblasts displayed a polygonal morphology with cell-cell junctions in all cases. It is suggested that the contained Chinese medicines would promote the activities of the osteoblasts.
    Journal of Wuhan University of Technology-Mater Sci Ed 02/2013; 28(1). DOI:10.1007/s11595-013-0659-8 · 0.42 Impact Factor
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    ABSTRACT: The aim of this study is to investigate in vitro release and cell response to wear particles of ultrahigh molecular weight polyethylene loaded with alendronate sodium (UHMWPE-ALN), a potent bone resorption inhibitor. Wear particles of UHMWPE-ALN with different ALN contents (0.5 wt % or 1.0 wt %) and size ranges (<45 μm or 45-75 μm) were cocultured with macrophages (RAW264.7) and osteoblasts (MC3T3-E1), respectively. The in vitro ALN release was divided into three stages: an initial burst release, subsequent rapid release, and final slow release. The particle size and ALN content of UHMWPE-ALN wear particles affected the in vitro release mainly during initial burst and rapid release. Compared with the control cells, UHMWPE-ALN wear particles stimulated a significant elevation of tumor necrosis factor-alpha (TNF-α) release from macrophages but had no obvious effect on interleukin-6 release. However, this stimulation of TNF-α release could be reduced by ALN released from UHMWPE-ALN wear particles. The wear particle size had stronger effect of on the macrophages compared with the ALN concentration. After coculture with UHMWPE-ALN wear particles, osteoblast proliferation and alkaline phosphatase activities increased moderately with the increase in particle sizes and ALN concentrations. These results suggest that incorporation of ALN in UHMWPE-ALN may be an effective approach to prevent or reduce particles-induced osteolysis. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012.
    Journal of Biomedical Materials Research Part A 02/2013; 101A(2). DOI:10.1002/jbm.a.34327 · 3.37 Impact Factor
  • ACTA AGRONOMICA SINICA 01/2013; 40(10):935. DOI:10.3724/SP.J.1206.2013.00285
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    ABSTRACT: Carbon nanotubes (CNTs)/hydroxyapatite (HA) nanocomposites with ferromagnetic properties have been fabricated via an in situ process in which a HA-based matrix was used as the catalyst for the growth of CNTs in a chemical vapor deposition system. The results showed that approximately 20 wt% of multi-walled CNTs with a mean diameter of 40–60 nm have been produced in the nanocomposites. The CNTs in the nanocomposites were observed to have an undamaged structure, with ordered graphitic layers and non-defective lattice structure on their walls. The growth of CNTs are shown to be in situ from the nano-HA crystallites. The compress mechanical properties of these CNTs/HA composites prepared by this method were significantly better than that of the composites prepared by physical mixing CNTs with HA particles. Magnetic measurement showed that the nanocomposites exhibit a ferromagnetic behavior with a saturation magnetization of 0.126 emu g−1 at a room temperature. These magnetic nanocomposites could have a potential application in the drug delivery system as well as other biomedical fields.
    Applied Surface Science 12/2012; 262:110–113. DOI:10.1016/j.apsusc.2012.02.139 · 2.54 Impact Factor
  • 09/2012; 4(16):400-408. DOI:10.4156/aiss.vol4.issue16.47
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    ABSTRACT: HA/PVA composites at different weight ratios were prepared by in situ growth of HA crystallites in PVA gels, and some interesting shape memory behaviors were investigated. Those results showed that HA/PVA composites at a weight ratio of 1:20, 1:10, and 1:5 had desirable shape memory effects. The initial shapes of pure PVA and HA/PVA composites were recovered automatically in 40 s and HA particles in PVA-matrix composites played an important role during the shape memory recovery.
    Polymer-Plastics Technology and Engineering 09/2012; 51(13). DOI:10.1080/03602559.2012.701364 · 1.48 Impact Factor
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    ABSTRACT: In the present work, porous titanium with a porosity of 70% was prepared using the space-holder sintering process. Then the porous titanium was treated by micro-arc oxidation (MAO) in the aqueous electrolyte. The results showed that TiO layers were formed on titanium at applied voltages (90–100 V) and in short time (1–3 min). The morphology of the TiO layer was investigated and the apatite-inducing ability was evaluated in a modified simulated body fluid (2 SBF). It revealed that the increases of MAO time and applied voltage contributed to the formation of bioactive apatite on the surface of film on the porous titanium scaffold. The TiO layer possesses high apatite-forming ability. Therefore, the TiO layer prepared by MAO can be used to modify the surface of the porous titanium implants.
    Applied Surface Science 07/2012; 258(19):7584–7588. DOI:10.1016/j.apsusc.2012.04.093 · 2.54 Impact Factor
  • Jie Shi · Bo Feng · Xiong Lu · Jian-Xin Wang · Ke Duan · Jie Weng
    Journal of Inorganic Materials 12/2011; 26(12):1299-1303. DOI:10.3724/SP.J.1077.2011.01299 · 0.54 Impact Factor

Publication Stats

81 Citations
56.09 Total Impact Points

Institutions

  • 2009–2015
    • Southwest Jiaotong University
      • • School of Materials Science and Engineering
      • • Key Laboratory of Advanced Technology of Materials (Chinese Education Ministry)
      Hua-yang, Sichuan, China