A novel strategy for preparing nanoporous biphasic calcium phosphate of controlled composition via a modified nanoparticle-assembly method

Keiko Fujiwara, Masahiro Okada, Shoji Takeda, Naoyuki Matsumoto

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Biphasic calcium phosphate (BCP) consisting of hydroxyapatite (HAp) and β-tricalcium phosphate is usually prepared by thermal decomposition of calcium-deficient HAp (CDHAp). However, the calcium deficiency and morphology of CDHAp are difficult to manipulate in parallel. In this study, we report a novel strategy for controlling the composition of nanoporous BCP by using only CDHAp nanoparticles with specific properties (Ca/P molar ratio, 1.61; particle size, 50 nm) as a building block and by adjusting the calcium deficiency of the nanoparticle-assembled CDHAp (Ca/P molar ratio, 1.50-1.67; pore size, 8 nm) with the addition of water-soluble Ca(NO3)2 or (NH 4)2HPO4. After thermal treatment at 1000 C, the composition of BCP could be predictably controlled by adjusting the Ca/P ratio of the nanoparticle-assembled CDHAp. Changes in the Ca/P ratio did not significantly affect the surface morphology of BCP, but the grain size (210-300 nm) and pore size (140-170 nm) tended to increase slightly as the Ca/P ratio decreased. The porosity significantly decreased upon the addition of Ca salts (porosity, 20%) or PO4 salts (porosity, 14%) compared with that of the sample without additives (porosity, 53%). In vitro tests demonstrated enhanced cell adhesion on nanoporous BCP compared with densely sintered pure HAp, and cell differentiation was promoted on the nanoporous pure HAp.

Original languageEnglish
Pages (from-to)259-266
Number of pages8
JournalMaterials Science and Engineering C
Volume35
Issue number1
DOIs
Publication statusPublished - Feb 1 2014
Externally publishedYes

Fingerprint

calcium phosphates
Calcium phosphate
Nanoparticles
calcium
Calcium
assembly
Porosity
Durapatite
nanoparticles
porosity
Hydroxyapatite
Chemical analysis
Pore size
Salts
Hot Temperature
adjusting
salts
Particle Size
Cell Adhesion
Cell adhesion

Keywords

  • Assembly
  • Calcium phosphate
  • Nanoparticle
  • Nanopore
  • Osteoblast

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering
  • Mechanics of Materials
  • Medicine(all)

Cite this

A novel strategy for preparing nanoporous biphasic calcium phosphate of controlled composition via a modified nanoparticle-assembly method. / Fujiwara, Keiko; Okada, Masahiro; Takeda, Shoji; Matsumoto, Naoyuki.

In: Materials Science and Engineering C, Vol. 35, No. 1, 01.02.2014, p. 259-266.

Research output: Contribution to journalArticle

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