Bioactive Ti Metal with Ca-Enriched Surface Layer Able to Release Sr Ions

Abstract:

Bioactive Ti metal able to release Sr ions was prepared by chemical and heat treatments of Ti metal. Ti metal was initially soaked in 5M NaOH solution to form sodium hydrogen titanate. It was soaked in a mixed solution of CaCl₂ and SrCl₂ to replace its Na ions with Ca and Sr ions at a given range from 0.18 to 1.62 in Sr/Ca ratio. When it was heat-treated at 600 oC, it formed Sr-containing calcium titanate (SrCT) and rutile. The apatite formation in SBF of the treated metal was low, but increased markedly by subsequently soaking the metal in 1 M SrCl₂ solution at 80 oC. Thus, the treated metal gradually released Sr ions into phosphate-buffered saline up to 0.9 ppm. It is expected that the Ti metal formed with the bioactive SrCT layer could release Sr ions in a living body to promote bone formation, and bond to a living bone through an apatite.

• Periodical: Key Engineering Materials (Volume 587)
• Pages: 269-274
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.587.269
• Online since: November 2013
• Authors: Seiji Yamaguchi*, Shekhar Nath, Tomiharu Matsushita, Tadashi Kokubo
• Keywords: Apatite Formation, Calcium Titanate, Simulated Body Fluid (SBF), Sr Ion, Ti Metal

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