title: The biocompatibility of titanium in a buffer solution: compared effects of a thin film of TiO2 deposited by MOCVD and of collagen deposited from a gel.
abstract: This study aims at evaluating the biocompatibility of titanium surfaces modified according two different ways: (i) deposition of a bio-inert, thin film of rutile TiO(2) by chemical vapour deposition (MOCVD), and (ii) biochemical treatment with collagen gel, in order to obtain a bio-interactive coating. Behind the comparison is the idea that either the bio-inert or the bio-active coating has specific advantages when applied to implant treatment, such as the low price of the collagen treatment for instance. The stability in buffer solution was evaluated by open circuit potential (OCP) for medium time and cyclic voltametry. The OCP stabilized after 5.10(4) min for all the specimens except the collagen treated sample which presented a stable OCP from the first minutes. MOCVD treated samples stabilized to more electropositive values. Numeric results were statistically analysed to obtain the regression equations for long time predictable evolution. The corrosion parameters determined from cyclic curves revealed that the MOCVD treatment is an efficient way to improve corrosion resistance. Human dermal fibroblasts were selected for cell culture tests, taking into account that these cells are present in all bio-interfaces, being the main cellular type of connective tissue. The cells grew on either type of surface without phenotype modification. From the reduction of yellow, water-soluble 3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT cytotoxicity test), MOCVD treated samples offer better viability than mechanically polished Ti and collagen treated samples as well. Cell spreading, as evaluated from microscope images processed by the program Sigma Scan, showed also enhancement upon surface modification. Depending on the experimental conditions, MOCVD deposited TiO(2) exhibits different nanostructures that may influence biological behaviour. The results demonstrate the capacity of integration in simulated physiologic liquids for an implant pretreated by either method.
authors.affiliation: General Chemistry Department, Faculty of Applied Chemistry and Material Science, UPB, str. Polizu, nr. 1-7, cod 011061, Bucharest, Romania.
authors.forename: Simona
authors.initials: S
authors.lastname: Popescu
authors.forename: Ioana
authors.initials: I
authors.lastname: Demetrescu
authors.forename: Christos
authors.initials: C
authors.lastname: Sarantopoulos
authors.forename: Alain N
authors.initials: AN
authors.lastname: Gleizes
authors.forename: Dana
authors.initials: D
authors.lastname: Iordachescu
mesh_terms: D002021:Buffers; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D003094:Collagen / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D005782:Gels / Q000378:metabolism*; D006801:Humans; D008422:Materials Testing; D013499:Surface Properties; D054457:Tissue Scaffolds / Q000737:chemistry; D014025:Titanium / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D014835:Volatilization
chemical_list: D002021:Buffers; D020099:Coated Materials, Biocompatible; D005782:Gels; C009495:titanium dioxide; D003094:Collagen; D014025:Titanium