Sr2+-Substituted CaCO3 Nanorods: Impact on the Structure and Bioactivity

Author(s)

Tovani, Camila B. ^[1] ; Oliveira, Tamires M. ^[1] ; Gloter, Alexandre ^[2] ; Ramos, Ana P. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Quim, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Ribeirao Preto, SP - Brazil

^[2] Univ Paris 11, Lab Phys Solides, CNRS UMR 8502, F-91405 Orsay - France

• Document type: Journal article
• Source: Crystal Growth & Design; v. 18, n. 5, p. 2932-2940, MAY 2018.
• Web of Science Citations: 5

Abstract

Strontium is a natural trace element found in biominerals such as aragonitic coral skeletons and bone apatite. Sr2+ substitution in biomaterials has been found to regulate the cellular metabolism, thus enhancing bone healing. Even though Ca2+ substitution for Sr2+ has been described in many phosphate minerals, the impact of such substitution on bioactivity and structure in pure carbonate phases has not been explored. Therefore, here we used a biomimetic approach to synthesize carbonate particles with a controlled size in which Ca2+ was progressively substituted for Sr2(+). Through structural investigation by X-ray diffraction, Raman spectroscopy, and electron microscopy techniques including high-resolution transmission electron microscopy and electron diffraction, we studied the precipitation mechanism of Sr-substituted CaCO3 nanorods showing that increasing Sr (2+)/(Ca2+ + Sr2+) molar fractions lead to stabilization of strontianite, a mineral from the aragonite group, increasing the carbonate crystalline lattice and particle crystallinity. The in vitro bioactivity evaluation attested that the particles bioactivity is maintained even at high Sr2+ concentrations. These outcomes are fundamental for proper evaluation of the role Sr2+ plays in carbonate based biomaterials properties and biomineralization and constitute a starting point to explore (Ca-Sr)CO3 particles as the next generation of bioactive materials for bone replacement. (AU)

• FAPESP's process: 17/08892-9 - Bioactive surfaces designed from Langmuir-Blodgett Films and Biominerals
• Grantee: Ana Paula Ramos
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/24249-0 - Association of osteogenic proteins in biominerals and metallic oxides doped with rare-earth: interaction with membrane models systems
• Grantee: Camila Bussola Tovani
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)