Papers by Keyword: Blood Compatibility

Abstract: In this paper, the in vitro blood compatibility of micro-arc oxidation (MAO) alumina coatings prepared in different times on biomedical NiTi alloy was studied using hemolysis ratio, dynamic blood clotting and platelet adhesion. The results show that the blood compatibility of the coated NiTi alloy is much better than that of uncoated NiTi alloy and reduces with increasing the micro-arc oxidation treatment times. Therefore, it can be concluded that the blood compatibility of materials is mainly dominated by the surface species contacted with blood within some ranges of surface roughness, not the surface morphologies, and the MAO alumina coatings can effectively improve the blood compatibility of NiTi alloy

Abstract: Heparin-like anticoagulant materials have been intensively studied over the past several years, many of effective works focus on the preparation of homogeneous sulfonated polymer and further anticoagulation and filtration properties.1 Due to high water-soluble properties of homogeneous materials, its applied scope is limited. In this study, nanofibrous membrane of cellulose acetate is chosen. By controlling degree of hydrolysis on the membrane surface and its further surface sulfonation, heparin-like surface has been built on cellulose derivative membranes where there are plenty of sulfonic acid group. In this paper, some testing means such as surface contact angle, ATR-FTIR, XPS and platelet adhesion are used to characterize membrane properties. The results show that our research approach is feasible, effects of hydrolysis and sulfonation are obvious on cellulose acetate membranes. In the meantime, the surface hydrophilicity of membrane is increased significantly; In addition, patelet adhesion experiments show that platelets adsorption decrease obviously after heparin-like treatment on the cellulose acetate membrane, showing an excellent anticoagulant activity.

Abstract: Nano-sized silicon dioxide (SiO₂) is widely utilized in artificial bone, artificial tooth, interventional catheters and drug delivery system，so it is imperative to study SiO₂ NPs on the role of the body damage. Consulted with standard reference of GB/T16886, 20 and 80 nm SiO₂ NPs were selected to prepare suspension (1mg/ml) for subacute systemic toxicity; 2000mg/ml suspension for MTT; and extracts (0.1g/ml) for hemolytic test. The results show that the hemolysis rate are all more than 5%, after its continuous injection of 2W nanoparticles into SD rats and New Zealand Rabbits, the alterations on the hemoglobin, hematocrit, mean corpuscular volume and other indicators have gained in blood routine test, and there was a marked inhibition on the L929 cells of SiO₂ NPs. Therefore, these two kinds of particle size of SiO₂ NPs have certain extent of injury effect on the blood system, and the contact time of NPs in the blood compatibility evaluation has play a more important role than the others.

Abstract: Owing to its high mechanical strength, chemical inertness, low frictional coefficient, high wear and corrosion resistance properties and so on, carbon nanotubes (CNTs) films have emerged as a potential material for biomedical applications. In order to investigate the blood compatibility properties of CNTs films synthesized on the silicon (Si) substrate using thermal chemical vapor deposition, the blood compatibility was evaluated in vitro by the platelet adhesion and the activated partial thromboplastin time (APTT). The experimental results demonstrated that the Si-CNTs films reduced thrombus formation by minimizing the platelet adhesion, activation , aggregation and had a tendency to retard the intrinsic coagulation activities of blood due to a higher APTT compared to Si, lower temperature isotropic pyrolytic carbon (LTIC) and Polydimethylsiloxane (PDMS) materials. Further, we found that hydrophobic surfaces are more prone to direct cellular motility in comparison with hydrophilic surfaces. It is concluded that CNTs films on the Si substrate were effective for improvement of blood compatibility.

Abstract: TiO2 thin film containing SrFe12O19 powders on the surface of 316L stainless steel and NiTi alloy was prepared through sol-gel method and micro-magnetic field was established by the magnetization process applied on the coating. The coating film was characterized by x-ray diffraction (XRD) and the surface morphology of the coating was observed by scanning electron microscope (SEM). This blood compatibility thin film was evaluated by dynamic cruor time of blood test.The results show that dynamic cruor time of blood is prolonged by the micro-magnetic field of the thin film, indicating improved blood compatibility.

Abstract: Biomaterials with good biocompatibility and anti-bacterial property were becoming attractive to researchers, so we used the chemical method to produce anti-bacterial vacuum plasma sprayed titanium coatings and studied In vitro bioactivity, cytotoxicity and blood compatibility of the anti-bacterial coatings in this paper. In order to evaluate the bioactivity of the treated titanium coatings, the coatings were immersed in simulated body fluid (SBF). The treated titanium coatings showed good bioactivity in this experiment. Two different methods were used to assess the cytocompatibility of the treated titanium coatings. One was extract test; the other was direct contact test. The results indicated that cells spread and adhered well on the coatings. The blood compatibility of the coatings was evaluated by haemolysis ratios. The hemolysis ratios of the coatings were below 2%, indicating of nonhemolysis for the coatings.

Abstract: The magnetic Fe3O4 nanoparticles had been synthesized by co-precipitation process and surface treatment by silane coupling agent (KH570). The magnetic Fe3O4/PMMA nanocomposite films were prepared by blend method, and the chemical structure, mechanical properties, surface morphology and the biocompatibility of the nanocomposite films were studied in this work. The magnetic Fe3O4 nanoparticles were well dispersed in the Fe3O4/PMMA nanocomposite films. The strength of the nanocomposite films, as well as the strain, decreased first and then increased with the increasing of the nanoparticles. The hemolytic ratio indicated that the nanocomposite films had a better blood compatibility.

Abstract: Epoxidized castor oil-based polyurethane were synthesized with epoxidized castor oil (ECO) and isophorone diisocyanate (IPDI) as the main raw materials. Epoxidized castor oil-based polyurethane (ECOPU) films were impregnated in different concentrations of chitosan (CS) solution containing acetic acid to prepare CS/ECOPU composite film. The structure and morphologies of the film have been characterized by means of mass change test, infrared spectroscopy, and optical polarization microscope. The recalcification time and dynamic blood-clotting tests were used to characterize the blood compatibility of CS/ECOPU composition film. The result showed that CS has been grafted onto the surface of ECOPU film. The material had good blood compatibility, and can be used as biomedical materials.

Abstract: For an application as biomedical materials of high performance with a good biocompatibility, the Ti-O film on Si (110) wafer substrate has been synthesize by means of unbalance reactive magnetron sputtering method and modified by phosphorus ion implantation and succeeding vacuum annealing. X-ray diffraction (XRD) results indicated that such prepared Ti-O film had a rutile structure. X-ray photoelectron spectroscopy (XPS) analysis demonstrates the effect of P ion doping. The contact angle test and sheet resistance results showed that titanium oxide film and phosphorus-doped titanium oxide film became more hydrophilic and higher conductance after annealing. The morphology and roughness of the surface have been investigated using SEM. Antithrombotic property of the titanium oxide thin film was examined by platelet adhesion tests. The results showed that the undoped Ti-O films and the P implant and annealing at 900 °C Ti-O film had good blood compatibility.

Abstract: Non-stoichiometric titanium dioxide (TiO2-x) thin films were obtained by unbalanced reactive pulsed magnetron sputtering and subsequently modified by hydrogen plasma. To investigate the influence of hydrogen plasma on the properties of the films, time and temperature were changed during the process with a fixed vacuum pressure of 10 Pa. The film structure, composition, resistance and blood compatibility were studied. The results that the concentration of Ti4+ decreases with the increasing of treated time and substrate temperature, which results in existence of oxygen vacancy and increase of conductivity. It is found that Ti-O film treated in 110°C plasma for 15min represents the lowest thrombosis risks, which could be mainly attributed to its characteristic of n-type semiconductor caused by appropriate oxygen vacancy forming in hydrogen plasma treatment.