Isotropic freeze casting of through-porous hydroxyapatite ceramics

The objectives of this study are to prepare a porous hydroxyapatite ceramic which has dentin tubule-like structure and determine its permeability. Slurry of hydroxyapatite powder, deionized water and a binder was poured into a ring which was placed on a freezing plate.The hydroxyapatite slurry was freezed in a certain rate (by controlling the temperature of the freeze plate at −15°C, −30°C and −45°C) for a certain period of time, then the freezed sample was freezing dried to remove the frozen vehicle, followed by being sintered at 1250 °C for 2 h. After that，the morphology of the cross section and longitudinal section of the sintered porous hydroxyapatite ceramic was observed by SEM and the hydraulic conductance of cross section discs of the sintered porous hydroxyapatite were determined using a self-made micro-flowing permeability tester. Results showed that the prepared hydroxyapatite ceramics having bottom-up unidirectional comblike tubule structure and the tubule diameters associated with the temperature of freezing plate.The ceramic discs prepared on the freezing plate of −45°C exhibited similarity to nature dentin tubule, with a diameter of 9.72±3.41mm and a hydraulic conductance of 0.16±0.09 ml×min-1×cm-2×cm×H2O-1.

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C-src oncogene mRNA expression in porous hydroxyapatite ceramics

Bioceramics ◽

10.1016/b978-008042692-1/50141-2 ◽

1997 ◽

pp. 595-598

Author(s):

K. Mishima ◽

H. Ohgushi ◽

T. Yoshikawa ◽

H. Nakajima ◽

E. Yamada ◽

...

Keyword(s):

Mrna Expression ◽

Porous Hydroxyapatite ◽

Hydroxyapatite Ceramics

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Effect of the Pore Structure of an Apatite-Fiber Scaffold on the Differentiation of P19.CL6 Cells into Cardiomyocytes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.782.116 ◽

2018 ◽

Vol 782 ◽

pp. 116-123

Author(s):

Yuzuha Ichikawa ◽

Kei Yasuda ◽

Masahiro Takahara ◽

Mamoru Aizawa ◽

Nobuyuki Kanzawa

Keyword(s):

Troponin T ◽

Specific Gene ◽

Porous Hydroxyapatite ◽

Spherical Carbon ◽

Functional Maturation ◽

Biomedical Device ◽

Hydroxyapatite Ceramics ◽

Proliferation And Differentiation ◽

Device Applications ◽

Radial Flow Bioreactor

We previously reported that P19.CL6 cells can be cultured in porous hydroxyapatite ceramics prepared by firing green compacts consisting of apatite fibers and spherical carbon beads (150 μm in diameter). Cells cultured for 20 days in an apatite-fiber scaffold (AFS) proliferated and differentiated into cells expressing troponin T, a cardiomyocyte-specific gene, but the expression level was insufficient to support the functional maturation of cells required for biomedical device applications. In this study, we aimed to optimize the internal AFS environment for cardiomyocytes by mixing two sizes (150-and 20-μm) of carbon beads. P19.CL6 cells were cultured in AFS materials comprising different carbon ratios in the presence of alpha-MEM with (AFS+) or without (AFS-) dimethyl sulfoxide (DMSO), and cell growth and gene expression were assessed. We found that AFS(50, 1:1 ratio) is the most suitable scaffold for the proliferation and differentiation of P19.CL6 cells and the addition of DMSO to the culture medium is necessary for differentiation into cardiomyocytes. We also assessed the culture of P19.CL6 cells in AFS in a radial-flow bioreactor for several days.

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