Lubrication coating is widely used to reduce the friction between the interventional devices and the blood vessels, improves the surface biocompatibility of the interventional device, and also brings the coating stability problems and related risks. This paper describes the coating-related content from the equipment description, performance verification, technical requirements, etc., to reduce the risk of the coating to an acceptable level.
Catheters ; Coated Materials, Biocompatible ; Friction ; Lubrication

The recovery force of Ti-Nb coated and uncoated TiNi shape memory alloy rods was investigated. The rods were 6.0 mm, 6.5 mm and 7.0 mm in diameter respectively. The mean transition temperature was 33.0 degrees C. The rods were stored at -18 degrees C and pre-bent with a three-point bending fixture, the span was 20. 0 centimeters and the deflections were 5.0 mm, 10.0 mm, 15.0 mm and 20.0 mm, respectively. The rods were then heated in a constant temperature saline solution chamber. The experimental temperature was 37.0 C and 50.0 C respectively. The recovery force was measured in a constant displacement mode on biomaterial test machine. The results showed that the recovery force of the memory alloy rod increased with increasing recovery temperature, rod diameter and deformation of both Ti-Nb coated and uncoated surface. The recovery force of Ti-Nb coated rods of 6.0 and 6.5 millimeter in diameter was lower than the uncoated rods in the same diameter. However, the recovery force of 7.0-mm-diameter rods showed no significant difference between coated and uncoated surface.
Alloys ; chemistry ; Biomechanical Phenomena ; Coated Materials, Biocompatible ; Niobium ; Temperature ; Titanium

OBJECTIVEThe aim of this study was to observe the change of bacterial adhesion on pure titanium coated with nitrogen-diamond like carbon (N-DLC) films and to guide the clinical application.

METHODSN-DLC was deposited on titanium using ion plating machine, TiN film, anodic oxide film and non-deposition were used as control, then made specimens adhering on the surface of resin denture base for 6 months. The adhesion of Saccharomyces albicans on the titanium surface was observed using scanning electron microscope, and the roughness was tested by roughness detector.

RESULTSThe number of Saccharomyces albicans adhering on diamond-like carbon film was significantly less than on the other groups (P < 0.05), and the growth of bacterial cell was inhibited and in a poor state. The largest number of adhesion and cell strains grew well on anodic oxide film group and non-deposition control group. The change of surface roughness of N-DLC film was less than other group (P < 0.05).

CONCLUSIONPure titanium coated with N-DLC film reduced the adhesion of Saccharomyces albicans after clinical application, thereby reduced the risk of denture stomatitis.

This is a report on the research of HA/Ti6Al4V composite implants that were successfully fabricated by radio frequency magnetron sputtering (RF-MS) technique. The mechanism and bioactivity of these implants immersed in simulated body fluid (SBF) were investigated. Changes in surface morphology, interfacial bond state, crystal structure and phase composition of HA coating before and after immersing in SBF were characterized by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Results indicate that a new substance on the surface of HA implant coatings produces accompanying with the dissolution of coatings. The substance is bone-like apatite containing CO3(2-) and lacking of Ca2+. Its ratio of n(Ca)/n(P) is about 1.56. This substance has very small grain size and similarly amorphous structure. Its structure and composition are similar to those of natural bone. Thus, it has good biocompatibility and bioactivity.
Biocompatible Materials ; Coated Materials, Biocompatible ; chemical synthesis ; Durapatite ; chemical synthesis ; Magnetics ; Materials Testing ; Prosthesis Implantation ; Radio Waves ; Titanium ; chemistry

Metal implants such as titanium, stainless steel and Co-Cr-Mo are used for load bearing purposes such as hip joint prostheses, fixing plates and dental root implants. For practical application, plasma-sprayed coatings of hydroxyapatite (HA) on metal implants are applied to promote early formation of strong bonds between metal implant and living bone. Plasma spray coating involves heating of HA material to a semi-molten or molten state and then propels its to a metal substrate. The plasma flame temperature is in the range of 6,000 degrees C to 16,000 degrees C but the surface temperature of the substrate rarely exceeds 150 degrees C. The HA materials are feed into the spray gun in the form of powders. Furthermore, this paper will discuss the processes of plasma-sprayed coating of HA on various types of metal implants.
Aerosols ; *Coated Materials, Biocompatible ; Heating ; *Materials Testing ; *Metals ; Microscopy, Electron, Scanning

To study the method of anodic oxidation followed by hydrothermal treatment for cp titanium and to know bone response to thin hydroxyapatite layers in vivo, commercially pure titanium plates were anodized at 200 V-400 V with direct electric current density no more than 50 mA/cm2 for 15 minutes in the electrolytic trough. beta-glycerophosphate sodium(0.03-0.04 M) and calcium acetate(0.2-0.3 M) were used as electrolytes. Then, titanium plates were hydrothermal treated in the autoclave for 2 hours at 280 degrees C-300 degrees C. Polishing and grit-blasting surface was used as control to learn bone response to thin layers. Twelve rabbits were evenly divided into 3 groups, each group was implanted with 12 implants into the rabbits femoral bone. After 4, 8 and 16 weeks, implants were taken out and collected respectively and were made grinding slices. The bone-implant interface was observed with light microscope. And the bone-implant interface of polishing and layered implants after 8 weeks implantation was observed with scanning electron microscope. The element contents at the interface of polishing and layered implants before and after 8 weeks implantation were detected with EDAX. Results showed that there was hydroxyapatite(HA) precipitated on the titanium surfaceamellae bone in 8 weeks for thin HA coatings, and no HA debris were found at the interfacial zone. In addition, Ca and P content on the hydrothermal treated implant surface increased much more after implantation than that of polished implants. It was concluded that anodic oxidation followed by hydrothermal treatment could precipitate thin hydroxyapatie layer on the surface of cp titanium, which could improve early formation of woven bone and accelerate woven bone transferring to lamellae bone at the implanted site.
Animals ; Coated Materials, Biocompatible ; chemistry ; Electrodes ; Hydroxyapatites ; chemistry ; Materials Testing ; Oxidation-Reduction ; Rabbits ; Titanium ; chemistry

All samples were divided into three groups and subjected to three different surface treatments, i.e. untreated group, group etched with mixed acid of 1:1 HCl and H2SO4 followed by immersion in 6N NaOH solution at 60 degrees C for 24 h and group etched with mixed acid of 1:1 HCl and H2SO4 followed by immersion in 6N NaOH solution at 60 degrees C for 24 h then heated at 600 degrees C for 1 h. After soaked in simulated body fluid for two weeks, a thin calcium phosphate coatings was precipitated on the surfaces of the two treated samples. Results of SEM and EDX showed that calcium phosphate coatings on the surfaces of the titanium samples etched and heated were more even than the titanium samples etched without heating. The analysis of XRD demonstrated the main component of calcium phosphate coating was hydroxyapatite.
Body Fluids ; chemistry ; Calcium Phosphates ; chemistry ; Coated Materials, Biocompatible ; chemistry ; In Vitro Techniques ; Materials Testing ; Titanium

OBJECTIVETo evaluate the genotoxicity of a magnesium alloy coated with beta-tricalcium phosphate (beta-TCP).

METHODSFour groups were designed. In the first group, AZ31B magnesium alloy surface was coated with beta-TCP using chemical bath deposition, and in the second group magnesium alloy was tested. The other two groups were negative control (pure titanium) and positive control groups (0.5 mg/L bleomycin). Single cell gel electrophoresis was adopted to investigate genotoxicity of the alloy samples in different groups, and 60 cells from each group were analysed. Tail moment and tail DNA percentage were used as reliable indicators to show DNA damage in lymphocytes induced by every testing sample. Student-Newman-Keuls (SNK) test was used to compare results from 4 groups.

RESULTSThere were no significant differences in tail moment and tail DNA percentage between magnesium alloy group [(0.52 +/- 0.12), (6.82 +/- 1.81)%] and magnesium alloy coated with beta-TCP group [(0.51 +/- 0.12), (6.89 +/- 1.93)%, P > 0.05]. Tail moment and tail DNA percentage in negative group were (0.47 +/- 0.14) and (6.29 +/- 1.64)%, and tail moment and tail DNA percentage in positive group were (5.17 +/- 1.23) and (22.09 +/- 4.51)%.

CONCLUSIONSNo significant increase was found in DNA damage in lymphocytes induced by magnesium alloy coated with beta-TCP.

The gradient bioceramics coating was prepared on the surface of Ti-6Al-4V alloy by using wide-band laser cladding. And the effect of technological parameters of wide-band laser cladding on microstructure and sinterability of gradient bioceramics composite coating was studied. The experimental results indicated that in the circumstances of size of laser doze D and scanning velocity V being fixed, with the increasement of power P, the density of microstructure in bioceramics coating gradually degraded; with the increasement of power P, the pore rate of bioceramics gradually became high. While P = 2.3 KW, the bioceramics coating with dense structure and lower pore rate (5.11%) was obtained; while P = 2.9 KW, the bioceramics coating with disappointing density was formed and its pore rate was up to 21.32%. The microhardness of bioceramics coating demonstrated that while P = 2.3 KW, the largest value of microhardness of bioceramics coating was 1100 HV. Under the condition of our research work, the optimum technological parameters for preparing gradient bioceramics coating by wide-band laser cladding are: P = 2.3 KW, V = 145 mm/min, D = 16 mm x 2 mm.
Ceramics ; chemistry ; Coated Materials, Biocompatible ; chemistry ; Lasers ; Materials Testing ; Surface Properties ; Titanium ; chemistry ; X-Ray Diffraction

The common complications of the endoprosthesis are occlusion of the stents, and cholangitis. There are many bacterial colonies in the blocked stents. Some studies have proved that the silver in a low concentration has the antimicrobial efficacy .The plastic biliary stents coated with nano-silver were prepared by the chemical redox process with plastic stents as carriers and silver nitrate as material. Then the friction coefficient and elastic modulus of the stents were detected by use of scanning electron microscope (SEM), transmission electron microscopy (TEM) and Energy Dispersive X-ray analysis (EDXA), scanning tunneling microscope (STM). The result shows that the nano-sliver coating is high purity and the nanoparticle is well-distributed, range of size is 5-80 nm. Antibacterial plastic biliary stents coated with nano-sliver that its surface is smooth and elasticity is not obvious change.
Anti-Bacterial Agents ; Biliary Tract ; Coated Materials, Biocompatible ; Materials Testing ; Nanoparticles ; Silver ; Stents