In situ study of partially crystallized Bioglass and hydroxylapatite in vitro bioactivity using atomic force microscopy.
The present work investigates, in situ, the in vitro bioactivity of partially crystallized 45S5 Bioglass (BG) as a function of immersion time in a simulated body fluid (SBF) using atomic force microscopy (AFM). The results obtained for the crystallized BG were compared to those of hydroxyapatite c- and a-faces. The calcium phosphate layer grows on the crystallized 45S5 B by multiple two-dimensional nucleation and fusion of these two-dimensional islands, which is essentially the same mode as for the hydroxyapatite c-face. The surface of the crystallized 45S5 BG was almost fully covered with a dense and compact calcium phosphate layer after 24 h. The calcium phosphate formation on the crystallized BG arises from a low surface energy of the surface layer and/or an effect of the layer to lower the resistance when the growth units of calcium phosphate incorporate into the growing island. These results indicate that the crystallized 45S5 BG is suitable to be used as a filler for polymeric matrix bioactive composites, as it maintains a high bioactivity associated with a stiffer behavior (as compared to standard BG).
Department of Polymer Engineering, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal. belinha@dep.uminho.pt
I B
IB
Leonor
A
A
Ito
K
K
Onuma
N
N
Kanzaki
Z P
ZP
Zhong
D
D
Greenspan
R L
RL
Reis
D001672:Biocompatible Materials / Q000493:pharmacokinetics; D001711:Biotransformation; D001826:Body Fluids / Q000378:metabolism; D002130:Calcium Phosphates / Q000737:chemistry / Q000493:pharmacokinetics; D002516:Ceramics / Q000493:pharmacokinetics*; D003460:Crystallization; D017886:Durapatite / Q000493:pharmacokinetics*; D005898:Glass; D007700:Kinetics; D018625:Microscopy, Atomic Force; D013499:Surface Properties
D001672:Biocompatible Materials; D002130:Calcium Phosphates; C485828:alpha-tricalcium phosphate; C425330:bioactive glass 45S5; C485830:tetracalcium phosphate; C485838:calcium phosphate, monobasic, anhydrous; D017886:Durapatite; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous