Influence of casein on the degradation process of polylactide-casein coatings for resorbable alloys.

This study used the dip-coating method to develop a new biocompatible coating composed of polylactide (PLA) and casein for ZnMg1.2 wt% alloy implants. It evaluated its impact on the alloy's degradation in a simulated body fluid. After 168 h of immersion in Ringer's solution, surface morphology analysis showed that the PLA-casein coatings demonstrated uniform degradation, with the corrosion current density measured at 48 µA/cm2. Contact angle measurements indicated that the average contact angles for the PLA-casein-coated samples were below 80°, signifying a hydrophilic nature that promotes cell adhesion. Fourier-transform infrared spectroscopy (FTIR) revealed no presence of lactic acid on PLA-casein coatings after immersion, in contrast to pure PLA coatings. Pull-off adhesion tests showed tensile strength values of 7.6 MPa for pure PLA coatings and 5 MPa for PLA-casein coatings. Electrochemical tests further supported the favorable corrosion resistance of the PLA-casein coatings, highlighting their potential to reduce tissue inflammation and improve the biocompatibility of ZnMg1.2 wt% alloy implants.

Influence of Hybrid Surface Modification on Biocompatibility and Physicochemical Properties of Ti-6Al-4V ELI Titanium.

Titanium-based materials are the most widely used materials in biomedical applications. However, according to literature findings, the degradation products of titanium have been associated with potential allergic reactions, inflammation, and bone resorption. The corrosion process of Ti-6Al-4V in the human body environment may be exacerbated by factors such as reduced pH levels and elevated concentrations of chloride compounds. Coatings made of biopolymers are gaining attention as they offer numerous advantages for enhancing implant functionality, including improved biocompatibility, bioactivity, wettability, drug release, and antibacterial activity. This study analyzes the physicochemical and electrochemical behavior of the Ti-6Al-4V ELI alloy subjected to PCL and PCL/TiO2 deposition by the electrospinning method. To characterize the polymer-based layer, tests of chemical and phase composition, as well as surface morphology investigations, were performed. Wetting angle tests were conducted as part of assessing the physicochemical properties. The samples were subjected to corrosion behavior analysis, which included open circuit potential measurements, potentiodynamic tests, and the electrochemical impedance spectroscopy method. Additionally, the quantification of released ions post the potentiodynamic test was carried out using the inductively coupled plasma atomic emission spectrometry (ICP-AES) method. Cytotoxicity tests were also performed. It was found that surface modification by depositing a polymer-based layer on the titanium substrate material using the electrospinning method provides improved corrosion behavior, and the samples exhibit non-toxic properties.