Reactivity and Corrosion Behaviors of Ti6Al4V Alloy Implant Biomaterial under Metabolic Perturbation Conditions in Physiological Solutions

Abstract

The corrosion of implant biomaterials is a well-known critical issue when they are in contact with biological fluids. Therefore, the reactivity of Ti6Al4V implant biomaterials is monitored during immersion in a Hanks’ physiological solution without and with added metabolic compounds, such as lactic acid, hydrogen peroxide, and a mixture of the two. Electrochemical characterization is done by measuring the open circuit potential and electrochemical impedance spectroscopy performed at different intervals of time. Electrochemical results were completed by morphological and compositional analyses as well as X-ray diffraction before and after immersion in these solutions. The results indicate a strong effect from the inflammatory product and the synergistic effect of the metabolic lactic acid and hydrogen peroxide inflammatory compound on the reactivity and corrosion resistance of an implant titanium alloy.

Electrochemical and biological characterization of Ti–Nb–Zr–Si alloy for orthopedic applications

“…Recent studies suggested that BSA adsorbs on titanium surfaces by electrostatic interactions or chemisorption through amino/ www.nature.com/scientificreports/ carboxylate groups, decreasing the rate of cathodic reduction of H 2 O 2 [46][47][48] . The same behavior has been reported in the addition of the CLH to the H 2 O 2 -containing solutions, which significantly blocks the cathodic site by adsorption on the surface, resulting in lower values of the OCP 28,29 . This does however not mean that the BSA and CLH inhibit the corrosion of Ti in the severe inflammatory medium and it seems necessary to perform PDP and EIS tests for further electrochemical studies.…”

“…The passive protective film on titanium in these conditions start to undergo degradation, accelerating corrosion rate and causing surface roughening and formation of intensely hydrated porous TiOOH compound [22][23][24][25] . Recent studies showed that the combination of albumin and H 2 O 2 accelerated the corrosion rate of CP-Ti and Ti-6Al-4V 26,27 and the presence of lactic acid and H 2 O 2 decreased the corrosion resistance considerably 28,29 . As a result of the complicated in vivo environment, corrosion of Ti…”

“…The increased corrosion resistance in inflammatory and severe inflammatory conditions can be attributed to the catalytic decomposition of H 2 O 2 to H 2 O and O 2 during the 12 h immersions decrease the oxidizing power of the solutions 43,53 . From anodic branches of PDP curves it is seen that specimens had passive behavior in the normal media but not in the inflammatory and severe inflammatory conditions 23,27,29 . As seen in Fig.…”

Enhancement of Corrosion Resistance Properties of Electrodeposited Ni/nano-TiC Composite Layers

“…In Figure 7 , R s represents the resistance of the solution between the reference electrode and the working electrode, R 1 is the specific resistance of the pure Ni layer, R 2 is the specific resistance of the Ni/nano-TiC composite layer and CPE is a constant phase element, which was used to simulate impedance data when the Nyquist diagram was not a perfect semicircle, possibly due to the uneven and inhomogeneous surface of the electrode. The impedance of such an electrochemical system with a CPE is expressed by Equation (2) [ 30 , 31 ]. where the CPE parameter, α, is also known as the CPE exponent and Q is the magnitude of CPE measured in F cm −2 s α −1 ; j is an imaginary number, j = ; is the angular frequency expressed in rad s −1 ; and f is the frequency in Hz (2π f ).…”

“…Figure 6 b and Figure 8 b, which represent the impedance modulus as a function of frequency, show that the slope of the transition region between the limits of the two asymptotes, indicating the power of the dependency of the imaginary part of the impedance on the frequency [ 30 ], was different for the two layers. The analysis of the slopes showed a higher value for the Ni/nano-TiC layer that slightly increased for both immersion periods.…”