In vitro properties of bioceramic coatings produced on zirconium by plasma electrolytic oxidation

Kalkan

et al. 2021

Sci Rep

Self Cite

Ca-based porous and rough bioceramic surfaces were coated onto zirconium by micro-arc oxidation (MAO). Subsequently, the MAO-coated zirconium surfaces were covered with an antimicrobial chitosan layer via the dip coating method to develop an antimicrobial, bioactive, and biocompatible composite biopolymer and bioceramic layer for implant applications. Cubic ZrO2, metastable Ca0.15Zr0.85O1.85, and Ca3(PO4)2 were detected on the MAO surface by powder-XRD. The existence of chitosan on the MAO-coated Zr surfaces was verified by FTIR. The micropores and thermal cracks on the bioceramic MAO surface were sealed using a chitosan coating, where the MAO surface was porous and rough. All elements such as Zr, O, Ca, P, and C were homogenously distributed across both surfaces. Moreover, both surfaces indicated hydrophobic properties. However, the contact angle of the MAO surface was lower than that of the chitosan-based MAO surface. In vitro bioactivity on both surfaces was investigated via XRD, SEM, and EDX analyses post-immersion in simulated body fluid (SBF) for 14 days. In vitro bioactivity was significantly enhanced on the chitosan-based MAO surface with respect to the MAO surface. In vitro microbial adhesions on the chitosan-based MAO surfaces were lower than the MAO surfaces for Staphylococcus aureus and Escherichia coli.

Section: Methodsmentioning

confidence: 99%

In vitro biological and antimicrobial properties of chitosan-based bioceramic coatings on zirconium

Aktuğ

Kalkan

et al. 2021

Sci Rep

Self Cite

“…In this study, the MAO device (MDO-100WS-100 kW) operated with AC (alternating current) power supply was used as preferred in our previous studies [38][39][40][41][42] . The Zr substrates were served as an anode (working electrode) as stainless steel container was served as a cathode through the MAO process.…”

Section: The Mao Coating Productionmentioning

confidence: 99%

“…The MAO electrolyte consisted of 0.25 M calcium acetate and 0.06 M β-calcium glycerophosphate. The electrolyte was prepared by dissolving of all chemicals into de-ionized water [38][39][40][41][42] . The MAO coating productions was carried out at 0.292 A/cm 2 for 10 min.…”

Section: The Mao Coating Productionmentioning

confidence: 99%

In Vitro Biological and Antimicrobial Properties of Chitosan-based Bioceramic Coatings on Zirconium

Aktuğ

Kalkan

et al. 2021

Preprint

Self Cite

Ca-based porous and rough bioceramic surfaces were coated on zirconium by micro arc oxidation (MAO). Subsequently, an antibacterial chitosan layer was covered on the MAO-coated zirconium surfaces by dip coating method to develop an antibacterial, bioactive and biocompatible composite biopolymer and bioceramic layer for implant applications. The cubic-ZrO2, meta-stable Ca0.15Zr0.85O1.85, and Ca3(PO4)2 were detected on the MAO surface by powder-XRD. The existence of chitosan on the MAO-coated Zr surfaces was verified by FTIR. The micro-pores and thermal cracks on the bioceramic MAO surface were sealed by chitosan coating, while the MAO surface is porous and rough. All elements such as Zr, O, Ca, P and C were homogenously distributed through both surfaces. Moreover, both surfaces indicated hydrophobic properties. However, the contact angle value of the MAO surface was lower than the one of chitosan-based MAO surface. In vitro bioactivity on both surfaces was investigated by XRD, SEM and EDX analyses at post-immersion in simulated body fluid (SBF) up to 14 days. In vitro bioactivity was significantly enhanced on the chitosan-based MAO surface with respect to the MAO surface. In vitro bacterial adhesions on the chitosan-based MAO surfaces were lower compared to the MAO surfaces for Staphylococcus aureus and Escherichia coli.

“…Also, at post-immersion in SBF, FTIR spectrum analysis results such as wave numbers, band modes, band assignments and phase were presented in Table 5. The band structures obtained on both surfaces at post-immersion in SBF are (PO 4 3− ), (C-C), (CO 3 (OH − ), respectively [22,43,[78][79][80][81][82][83][84][85][86][87][88][89][90][91][92][93][94][95]. The ATR-FTIR peaks of both surfaces verify the presence of (C-C) at 1403 cm −1 [43,[78][79][80], the presence of (OH − ) ion at 1641 cm −1 [43,78,79] and the presence of (Ti-O-Ti) in the regions of 3397-3448 cm −1 [43,[78][79][80].…”

Section: In Vitro Bioactivity Of the Coatingsmentioning

confidence: 99%

“…In addition to XRD spectra, the presence of TiO 2 structure on both surfaces are indicated by the bands of (C-C), (OH − ) and (Ti-O-Ti) on FTIR once again [43,[78][79][80]. The FTIR spectra curves on both surfaces refer to the presence of (PO 4 3− ) at 560 cm −1 [81][82][83] and 1026 cm −1 [83][84][85][86], the presence of (PO 4 3− ) at 962 cm −1 [83][84][85][86][87] and 1050 cm −1 [83][84][85][86][87], the presence of (P-H) in the regions of 1980 cm −1 [88][89][90][91][92][93] and 2302-2388 cm −1 [88][89][90][91][92][93] and the presence of (OH − ) at 3640-3742 cm −1 [88,[91][92][93][94]. The apatite and TCP structures formed on both surfaces at post-immersion in SBF are proved by the presence of (PO 4 3− ), (P-H) and (OH − ) bands on FTIR curves [81][82][83][84][85][86][87]…”

Section: In Vitro Bioactivity Of the Coatingsmentioning

confidence: 99%

Characterization, Bioactivity and Antibacterial Properties of Copper-Based TiO2 Bioceramic Coatings Fabricated on Titanium

2018

Coatings

Self Cite

The bioactive and anti-bacterial Cu-based bioceramic TiO 2 coatings have been fabricated on cp-Ti (Grade 2) by two-steps. These two-steps combine micro-arc oxidation (MAO) and physical vapor deposition-thermal evaporation (PVD-TE) techniques for dental implant applications. As a first step, all surfaces of cp-Ti substrate were coated by MAO technique in an alkaline electrolyte, consisting of Na 3 PO 4 and KOH in de-ionized water. Then, as a second step, a copper (Cu) nano-layer with 5 nm thickness was deposited on the MAO by PVD-TE technique. Phase structure, morphology, elemental amounts, thickness, roughness and wettability of the MAO and Cu-based MAO coating surfaces were characterized by XRD (powder-and TF-XRD), SEM, EDS, eddy current device, surface profilometer and contact angle goniometer, respectively. The powder-and TF-XRD spectral analyses showed that Ti, TiO 2 , anatase-TiO 2 and rutile-TiO 2 existed on the MAO and Cu-based MAO coatings' surfaces. All coatings' surfaces were porous and rough, owing to the presence of micro sparks through MAO. Furthermore, the surface morphology of Cu-based MAO was not changed. Also, the Cu-based MAO coating has more hydrophilic properties than the MAO coating. In vitro bioactivity and in vitro antibacterial properties of the coatings have been investigated by immersion in simulated body fluid (SBF) at 36.5 • C for 28 days and bacterial adhesion for gram-positive (S. aureus) and gram-negative (E. coli) bacteria, respectively. The apatite layer was formed on the MAO and Cu-based MAO surfaces at post-immersion in SBF and therefore, the bioactivity of Cu-based MAO surface was increased to the MAO surface. Also, for S. aureus and E. coli, the antibacterial properties of Cu-based MAO coatings were significantly improved compared to one of the uncoated MAO surfaces. These results suggested that Cu-based MAO coatings on cp-Ti could be a promising candidate for biomedical dental implant applications.TiO 2 -based coatings have been suggested to improve corrosion resistance, bioactivity and biocompatibility of implant surfaces. They have recently received great attention for the biomedical applications owing to their more stable chemical composition [11,12]. TiO 2 were fabricated on cp-Ti by various surface coating methods including sol-gel [13], anodic oxidation [14], magnetron sputtering [15], electrophoretic deposition [16], acid etching [17,18], laser surface treatment [19], plasma spraying [20,21] and micro arc oxidation [22][23][24][25] etc. However, certain problems like non-homogenous structure, micro-structural control problems, micro-cracks formation, the presence of phase impurity, poor adhesion strength were observed in these methods except for MAO technique [26][27][28]. Thus, implant application areas of the coatings produced by these techniques are limited.Micro-arc oxidation (MAO) is one of the most applicable methods to deposit a porous and rough bioceramic layer on valve metals such as Ti, Al, Mg, and Zr surfaces [3,[29][30][31]. The MAO coating promotes bioacti...