Lipid-mediated growth of SrCO3/CaCO3 hybrid films as bioactive coatings for Ti surfaces

Author(s)

Cruz, M. A. E. ^[1] ; Zanatta, M. B. T. ^[1] ; da Veiga, M. A. M. S. ^[1] ; Ciancaglini, P. ^[1] ; Ramos, A. P. ^[1]

Affiliation

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

• Document type: Journal article
• Source: Materials Science & Engineering C-Materials for Biological Applications; v. 99, p. 762-769, JUN 2019.
• Web of Science Citations: 1

Abstract

SrCO3 is frequently used as Sr2+ source in ceramic cements, but its application as bioactive coating for metallic implants has not been explored yet. Aiming at rapid osteointegration and because of the well-known Sr2+ effects on bone metabolism, researchers have sought to design Sr2+-containing biomaterials. In this context, developing simple techniques to prepare Sr2+-based coatings is a must nowadays. Here, we describe the use of a bioinspired lipid-mediated approach to grow SrCO3 hybrid films on Ti surfaces at room temperature. To obtain these coatings, we applied the Langmuir-Blodgett technique to deposit phospholipid films with high degree of organization on Ti. In this way, we expected that controlled SrCO3 crystal growth could be templated by the array of nucleation points arising from electrostatic interaction between Sr2+ and the phospholipid polar heads. To control surface composition and the amount of Sr2+ released from the coatings, we also promoted CaCO3 co-precipitation in the hybrid films. We characterized the hybrid coatings in terms of morphology, chemical structure, wettability, and ability to release Sr2+ upon immersion in biological medium. In vitro osteoblast culture on mixed SrCO3/CaCO3 films revealed that the osteogenic response depended on surface composition, as indicated by alkaline phosphatase activity overexpression, which is an early indicator of osteoblast differentiation. Results showed that the mixed SrCO3/CaCO3 hybrid film created a synergic environment for osteoblasts, and that proper Sr2+ release associated with a Ca2+-rich environment might have optimized the Sr2+-anabolic effect. In conclusion, we have proposed a bioinspired and versatile technique to grow hybrid films that can control surface composition and Sr2+ release. Our results open an opportunity to explore the use of SrCO(3)Z-based coatings for rapid metallic implant osteointegration. (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: 16/21236-0 - Extracellular matrix vesicles (MVs) mimetic systems to study the regulation of the biomineralization process: proteoliposomes containing NPP1 and Annexin V
• Grantee: Pietro Ciancaglini
• Support Opportunities: Regular Research Grants
• FAPESP's process: 15/08774-0 - Modification of Ti surfaces by Langmuir-Blodgett hybrid films containing biominerals and strontium ranelate to promote the controled Sr2+ release
• Grantee: Marcos Antonio Eufrásio Cruz
• Support Opportunities: Scholarships in Brazil - Master