Nickel–titanium alloy: Cytotoxicity evaluation on microorganism culture

Biocorrosion investigation of two shape memory nickel based alloys: Ni‐Mn‐Ga and thin film NiTi

“…edu toxic effects on bacteria or yeast microorganisms and that the microorganisms had a low adherence to thin film nitinol surface. 20 The authors attribute the favorable biological response to the minimal release of ions into solution. Thin film nitinol produced by other approaches may yield different results because of inherent differences in surface energies, grain size, and surface roughness.…”

“…[16][17][18][19] The biocompatibility of thin film nitinol has not been determined for all of these nitinol thin film fabrication approaches. However, Dinca et al 20 have studied the cytotoxicity of pulse laser deposited thin film nitinol on microorganisms. They found that thin film nitinol did not exhibit cytoCorrespondence to: L.L.…”

The Electrochemical Behavior of the NiTi Alloy in Different Simulated Body Fluids

“…Electrochemical and morphological results, show that the NiTi presents the same corrosion mechanism (pitting induced by Cl -and HCO 3 -ions) in all studied simulated body fluids. However, the Hanks solution demonstrated less aggressiveness in comparison to other simulated body fluids, which is evidenced by its less active corrosion potential and by the development of lowest current densitie values, probably due to a lower chloride concentration.…”

“…Considering the solutions that were analyzed at 37 °C, the Hanks solution demonstrated the lowest current densities in the passive zone of the polarization curve (Figure 2). This is probably associated to HCO 3 -ion concentration in the Hanks solution ( Table 1). The oxide layer was firstly ruptured, in Hanks solution, when the applied potential reached 99 mV (current density increased from 1.55 × 10 -7 A/cm 2 to 8.72 × 10 -7 A/cm²) while this value was -78 mV (current density increased for HBSS and -148 mV (current density increased from 2.80 × 10 -6 A/cm 2 to 1.39 × 10 -5 A/cm²) for SBF.…”

“…Comparative studies of biocompatibility between alloys 2 show that the solubilized nickel may present several adverse reactions. Despite the reports of some authors 3,4 of the lack of cytotoxicity of alloys, a study conducted by Fili 5 found that Ni-rich precipitates in NiTi osseous implants chemically passivized with HF, HNO 3 and H 2 O 300 days after implantation. A number of methodologies were proposed with the objective of creating a barrier that would block the release of nickel, resulting in an increased biocompatibility of the alloy and corrosion resistance: anodization 6,7 , heat treatments for superficial oxidation 8,9 , sputtering 10,11 , plasma electrolytic oxidation 12 , plasma immersion ion implantation 13 , hydroxiapatite/zirconia composite coating 14 , TiN coating 15 , sol-gel technology 16 metal vapor vaccum arc plasma source 17 .…”