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Abstract Objectives: To evaluate the mechanical, physicochemical, and antimicrobial properties of four different formulations containing micro- or nanoparticles of sodium trimetaphosphate (mTMP and nTMP, respectively). Methodology: Four experimental groups were used in this investigation: two mTMP groups and two nTMP groups, each containing zirconium oxide (ZrO2), and solution containing either chitosan or titanium oxide (TiO2) nanoparticles (NPs). Setting time, compression resistance, and radiopacity were estimated. The agar diffusion test was used to assess the antimicrobial activity of the formulations against five different microbial strains: Streptococcus mutans, Lactobacillus casei, Actinomyces israelii, Candida albicans, and Enterococcus faecalis. Parametric and nonparametric tests were performed after evaluating homoscedasticity data (p<0.05). Results: From the properties evaluated, nTMP cements required less setting time and showed greater resistance to compression. Cements containing TiO2 showed greater radiopacity for both nTMP and mTMP. All four cement formulations showed antimicrobial activity against S. mutans and L. casei Conclusion: Formulations containing nTMP have shorter setting times and higher compressive strength, and those with TiO2 nanoparticles showed antimicrobial activities. Clinical relevance: The cement containing nTMP, ZrO2, and TiO2 could be an alternative material for protecting the pulp complex.
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Objective Exploration of the titanium surface nano structure on the cellular bioactivity is of great significance to modifying the pure titanium surface. The unique cluster-like anatase/rutile nanowires (AR@NWs)was prepared and we further examined whether this surface was beneficial for early biological reaction in osteoblast.Methods Unique cluster-like anatase/rutile NWs(AR@NWs)was generated by using a simple hy-drothermal reaction via a three-step synthesis process.The crystal structure of nanowires on titanium surface was de-tected by X-ray diffractometer. The biological activity of nanowires was studied using in vitro cellular experiments. Results The AR@NWs was with a diameter of 200 nm. Three different types of NWs were generated during the production process,displaying different crystal structure and biological characteristics but similar surface topogra-phy and wettability.Compared with sodium titanate NWs(STi@NWs)and H2Ti2O5nanowires(HTi@NWs),AR@NWs surface was conductive to cell attachment. The data indicated that the surface titanium chemical composi-tion and crystal structure played an important role in the cell early response.To some extent,the generation of ana-tase and rutile compensated the cell-repelling properties of NWs. Conclusion Not only the surface physical prop-erties such as surface topography but also the surface chemistry plays an important role in promoting the cell early bioactivity.
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PURPOSE: The aim of this study was to evaluate the surface properties and biological response of an anodized titanium surface by cell proliferation and alkaline phosphatase activity analysis. METHODS: Commercial pure titanium (Ti) disks were prepared. The samples were divided into an untreated machined Ti group and anodized Ti group. The anodization of cp-Ti was formed using a constant voltage of 270 V for 60 seconds. The surface properties were evaluated using scanning electron microscopy, X-ray photoelectron spectroscopy, and an image analyzing microscope. The surface roughness was evaluated by atomic force microscopy and a profilometer. The contact angle and surface energy were analyzed. Cell adhesion, cell proliferation, and alkaline phosphatase activity were evaluated using mouse MC3T3-E1 cells. RESULTS: The anodized Ti group had a more porous and thicker layer on its surface. The surface roughness of the two groups measured by the profilometer showed no significant difference (P>0.001). The anodized Ti dioxide (TiO2) surface exhibited better corrosion resistance and showed a significantly lower contact angle than the machined Ti surface (P>0.001). Although there was no significant difference in the cell viability between the two groups (P>0.001), the anodized TiO2 surface showed significantly enhanced alkaline phosphatase activity (P<0.001). CONCLUSIONS: These results suggest that the surface modification of Ti by anodic oxidation improved the osteogenic response of the osteoblast cells.
Subject(s)
Animals , Mice , Alkaline Phosphatase , Cell Adhesion , Cell Proliferation , Cell Survival , Corrosion , Dental Implants , Durapatite , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Osteoblasts , Photoelectron Spectroscopy , Surface Properties , TitaniumABSTRACT
A highly sensitive electrochemical deoxyribonucleic acid(DNA) biosensor based on multi-walled carbon nanotubes(MWNT)/Ag-TiO_2 composite film was developed. The solution containing Ag-TiO_2-MWNT composite was casted on the carbon paste electrode surface to form a robust film, which combine the advantages of the good biocompatibility of Ag-TiO_2 naocomposite and the fine conductivity, as well as the large active surface area of carbon nanotubes. The composite could greatly improve the immobilization capacity of the probe DNA. The morphologies and electrochemistry of the nanocomposite film were investigated by scanning electron microscopy and electrochemical techniques including electrochemical impedance spectroscopy and cyclic voltammetry, respectively. DNA hybridization events were monitored by a label-free method of electrochemical impedance spectroscopy. This label-free electrochemical impedance DNA biosensor showed high sensitivity and selectivity for phosphinothricin acetyltransferase gene sequence assay. The multicomponents films also displayed a high stability during repeated regeneration and hybridization process.
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To investigate the influence of stainless steel(SS)and titanium oxide(Ti-O)thin films on the cytokine released by en-dothelial cells.Ti-O films were prepared by unbalanced magnetron sputtering deposition system(UBMS).Human umbilical vein en-dothelial cells(HUVECS)were isolated and seeded on SS and Ti-O materials.Nitride oxide (NO)and monocytc chemotactic protein one(MCP-1)concentrations were determined in the supematants with enzyme linked immunosorbent assay(ELISA)at 1,3 and 5 days after culture,and the morphology of the cells was observed using scanning electron microscopy(SEM).The results showed that the similar amount of HUVECs was presented in SS and Ti-O culture.But HUVEC had better morphology on Ti-O film than SS.The NO and MCP.1 test also showed that HUVECs on Ti-O film had a better bio-function than SS.It is concluded that Ti-O film as a biomaterial may have a better endothlieal compatibility,which can be used to enhance the endothelialization.
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To investigate the influence of stainless steel(SS)and titanium oxide(Ti-O)thin films on the cytokine released by en-dothelial cells.Ti-O films were prepared by unbalanced magnetron sputtering deposition system(UBMS).Human umbilical vein en-dothelial cells(HUVECS)were isolated and seeded on SS and Ti-O materials.Nitride oxide (NO)and monocytc chemotactic protein one(MCP-1)concentrations were determined in the supematants with enzyme linked immunosorbent assay(ELISA)at 1,3 and 5 days after culture,and the morphology of the cells was observed using scanning electron microscopy(SEM).The results showed that the similar amount of HUVECs was presented in SS and Ti-O culture.But HUVEC had better morphology on Ti-O film than SS.The NO and MCP.1 test also showed that HUVECs on Ti-O film had a better bio-function than SS.It is concluded that Ti-O film as a biomaterial may have a better endothlieal compatibility,which can be used to enhance the endothelialization.
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To investigate the influence of stainless steel(SS)and titanium oxide(Ti-O)thin films on the cytokine released by en-dothelial cells.Ti-O films were prepared by unbalanced magnetron sputtering deposition system(UBMS).Human umbilical vein en-dothelial cells(HUVECS)were isolated and seeded on SS and Ti-O materials.Nitride oxide (NO)and monocytc chemotactic protein one(MCP-1)concentrations were determined in the supematants with enzyme linked immunosorbent assay(ELISA)at 1,3 and 5 days after culture,and the morphology of the cells was observed using scanning electron microscopy(SEM).The results showed that the similar amount of HUVECs was presented in SS and Ti-O culture.But HUVEC had better morphology on Ti-O film than SS.The NO and MCP.1 test also showed that HUVECs on Ti-O film had a better bio-function than SS.It is concluded that Ti-O film as a biomaterial may have a better endothlieal compatibility,which can be used to enhance the endothelialization.
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BACKGROUND: Titanium dioxide (TiO2) thin film photocatalyst generates strong oxidizing power when illuminated with Ultra Violet (UV) light with wavelengths of less than 385 nm. In this study, we evaluated the bactericidal activity of it against Escherichia coli, Aspergillus fumigatus and Mycobacterium tuberculosis. METHODS: The TiO2 film were prepared from titanium isopropoxide solution and it was coated on either inner(test) or outer(control) side on Petri dish. annealing at 500 degrees C. The test and control suspension of E. coli, A. fumigatus and M. tuberculosis were grown in the chamber coated inner and outer side. respectively with UV light. For the blank, cell suspensions were grown in TiO2 coated Petri dishes without UV light. The bactericidal activities were estimated by survival ratio calculated from the number of viable cells which form the nutrient agar. RESULTS: In the test, the survival ratio for E. coli and M tuberculosis decreased to a negligible level (i.e., essentially complete sterilization) within 1hr and 2 hr, respectively. and that for 11. fumigatus decreased markedly to about 15% within 6 hr. In the control, the survival ratio for E. coli, A. fumigatus and M. tuberculosis decreased to 40% within 150 min. 6 he and 2 hr, respectively. In the blank, the survival ratio for E. coli and M tuberculosis decreased only about 67% within 150 min and 40% within 2hr. In A. fumigatus, TiO2 only caused little Sterilization within 4 hr. CONCLUSIONS: TiO2 photocatalysts under UV light clearly showed bactericidal activity against E. coli, A. fumigarus and M. tuberculosis. This feature render TiO2 photocatalysts to be applicable to eliminate microorganism from indoor air environment combined with ventilation.
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Agar , Aspergillus fumigatus , Aspergillus , Escherichia coli , Escherichia , Mycobacterium tuberculosis , Sterilization , Suspensions , Titanium , Tuberculosis , Ultraviolet Rays , Ventilation , ViolaABSTRACT
Objective:To evaluate the effects of surface modified nano titanium-oxide on the mechanical properties of A-2186 silicone elastomers. Methods:Added surface modified nano titanium-oxide into A-2186 silicone elastomers with 0.0%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0% additions according to the ASTM standard. The mechanical properties of A-2186 silicone elastomer including the tensile strength, the broken elongation, the tear strength and the Shore-A hardness were tested separately. The section of samples were investigated by scanning electron microscope and energy spectrum analysis. Used statistics method to analyse the results. The results were analysed with software EPSS 13.0. Results:With the addition of nano titanium-oxide increasing, the tensile strength, the broken elongation and the tear strength of A-2186 silicone elastomers increased firstly, and then decreased. While the Shore-A hardness of A-2186 silicone elastomers increased gradually. When the addition of surface modified nano titanium-oxide reached to 2.0%, the nano titanium-oxide dispersed well in the base without agglomeration. Under such condition, the A-2186 silicone elastomer showed the best general mechanical properties:the tensile strength was (6.54?0.55) MPa, the broken elongation was 618.00?7.58(%), the tear strength was (16.64?0.52) kN/m and the Shore-A hardness was (31.00?0.79) U. Conclusion:The mechanical properties of A-2186 silicone elastomers are improved most greatly with 2.0% addition of surface modified nano titanium-oxide to the base of A-2186 silicone elastomers.