Template-free synthesis of phosphate-based spheres via modified supersaturated phosphate buffer solutions

  • Tao QinEmail author
  • Yuanyuan Han
  • Peng Zhang
  • Ishtiaq Hassan Wani
  • Fredrik Nikolajeff
  • Klaus Leifer
  • Håkan Engqvist
Tissue engineering constructs and cell substrates Original Research
Part of the following topical collections:
  1. Tissue Engineering Constructs and Cell Substrates


Modified supersaturated phosphate buffer solutions were used to synthesize phosphate-based spheres, including calcium phosphate (CaP), strontium phosphate (SrP) and barium phosphate (BaP). A series of ions concentrations in the modified phosphate buffer solutions were investigated in order to study their effects in precipitates morphologies. During synthesis, it was found that magnesium was the key factor in sphere formation. The morphologies of calcium phosphate, strontium phosphate and barium phosphate precipitates varied as the concentration of magnesium ions varied. When sufficient magnesium was provided, the precipitates appeared spherical, and the diameter was in range of 0.5–2 μm. The morphologies, compositions and structure of spheres were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption analysis. Moreover, the application of magnesium substituted calcium phosphate spheres in dentin tubules occlusion was investigated.

Graphical Abstract

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The authors would like to thank the China Scholarship Council for providing financial support to this work. The authors would also like to thank Michael Pujari–Palmer for language and editing in this manuscript.

Conflict of interest

The authors declare that they have no competing interests.

Supplementary material

10856_2017_5911_MOESM1_ESM.docx (1.1 mb)
Supplementary Information


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  • Tao Qin
    • 1
    Email author
  • Yuanyuan Han
    • 1
  • Peng Zhang
    • 2
  • Ishtiaq Hassan Wani
    • 1
  • Fredrik Nikolajeff
    • 1
  • Klaus Leifer
    • 1
  • Håkan Engqvist
    • 1
  1. 1.The Division for Applied Material Science, Department of Engineering ScienceUppsala UniversityUppsalaSweden
  2. 2.The Division for Nanotechnology and Functional Materials, Department of Engineering ScienceUppsala UniversityUppsalaSweden

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