Enhancement of corrosion, biocompatibility and drug delivery properties of nitinol implants surface by Al-Zn-LDH nanohybrids

This study investigates the enhancement of drug delivery and corrosion resistance by incorporating dexamethasone sodium phosphate into aluminum-zinc layered double hydroxide (LDH) coated nickel-titanium alloys. The nickel-titanium samples were fabricated from titanium and nickel powders using spark plasma sintering (SPS) and cold press sintering (CPS), followed by electrophoretic deposition of LDH nanoparticles. This composite construction aims to utilize the biocompatibility and mechanical properties of nickel-titanium, combined with the controlled drug release and corrosion resistance properties of LDH coatings. Structural and microstructural characterizations were performed using X-ray diffraction and scanning electron microscopy. The results indicated that SPS samples exhibited superior microstructural homogeneity and corrosion resistance compared to CPS samples. Dexamethasone sodium phosphate was successfully intercalated into the LDH layers, as evidenced by an increase in layer spacing from 7.14 Å to 20.130 Å. The LDH-coated nickel-titanium with intercalated dexamethasone sodium phosphate demonstrated a 5 % lower drug release rate and significantly improved corrosion resistance compared to uncoated samples. Cell adhesion studies confirmed good biocompatibility between cells and the coated surface. This composite material shows promise for enhanced performance in biomedical applications, particularly in drug delivery and corrosion resistance.