Evaluation of Potential of Ti Foams as Drug Carriers and Study its Effect on Osseointegration

Abstract

Osseointegration of orthopedic implants can be improved by enhancing the bioactivity of a biocompatible material. In this study, porous titanium was employed as an orthopedic implant. It was infiltrated with gelatin-sodium alginate hydrogel loaded with strontiumdoped hydroxyapatite nanoparticles which were intended to be released to enhance osseointegration. Titanium implants were fabricated by arc melting a filler metal into titanium metal, followed by electrochemical dealloying to create foams. Strontium-doped hydroxyapatite nanoparticles were synthesized by the wet-precipitation method while hydrogel was crosslinked by physical crosslinking through calcium ions. Microstructural analysis was performed to confirm the synthesis of the fabricated nanoparticles, hydrogels, and nanoparticles-loaded hydrogels. Functional groups were observed for further confirmation of synthesis. Release of strontium-doped hydroxyapatite from the hydrogel and the foam was performed through UV-visible spectroscopy. The gelatin-sodium alginate blend hydrogel was found to degrade at physiological conditions releasing the nanoparticles. The initial burst release was 56% from the hydrogel film while it was reduced to 32% when the hydrogel was infiltrated in the titanium foam. Complete release of nanoparticles was observed to take place in 10 days from the hydrogel film while infiltration in foam caused 40% of the nanoparticles to be released in the same time period.