Mild Reaction of Highly-Oriented Collagen Fibril Arrays with Simulated Body Fluid

The highly-oriented collagen fibrils that paralleled to one (rubbing) direction were fabricated by which the collagen molecular solution was spin-coated and self-assembled on the rubbed polyimide film. Subsequently, the hydroxyapatite crystals were precipitated on the collagen fibrils by immersing into simulated body fluid. In details, the carboxyl groups on the collagen fibrils were used as a reaction field for adsorption of Ca2+ ions and promoted the formation of hydroxyapatite crystals. As a result, the hydroxyapatite crystals grew along the a-axis leading to the formation of stable interfaces between hydroxyapatite crystals and collagen fibrils. Moreover, the oriented collagen fibril arrays were more useful for the nucleation and growth of hydroxyapatite. Therefore, we successfully fabricated the highly-oriented collagen fibril arrays which were useful for the precipitation of hydroxyapatite crystals.

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Apatite Deposition on Polypeptides Derived from Plants in a Solution Mimicking Body Fluid

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.309-311.671 ◽

2006 ◽

Vol 309-311 ◽

pp. 671-674

Author(s):

Toshiki Miyazaki ◽

Chikara Ohtsuki ◽

Shinichi Ogata ◽

Masahiro Ashizuka

Keyword(s):

Simulated Body Fluid ◽

Body Fluid ◽

Mechanical Performance ◽

Extracellular Fluid ◽

Organic Polymer ◽

Carboxyl Groups ◽

Organic Substrates ◽

Ion Concentrations ◽

Inorganic Ion ◽

Apatite Deposition

Organic-inorganic hybrids composed of organic polymer and apatite is quite attractive as novel bone-repairing materials since it has mechanical performance analogous to those of natural bone as well as bone-bonding ability, i.e. bioactivity. To fabricate such an apatite-polymer hybrid, biomimetic process has been recently paid much attention. In this process, bone-like apatite is deposited on the surfaces of organic substrates in simulated body fluid (SBF, Kokubo solution) having ion concentrations analogous to those of human extracellular fluid or more concentrated solutions. Previous studies showed that the apatite deposition is triggered by a catalytic effect of carboxyl groups (COOH) on the surfaces of the organic substrates. In this study, we examined apatite deposition on natural polypeptides derived from crops in a biomimetic solution. We selected gluten derived from wheat and zein derived from corn. Both of gluten and zein formed bone-like apatite on their surfaces in a solution that has inorganic ion concentrations 1.5 times those of simulated body fluid, when they were treated with 1 mol/L calcium chloride solution. High content of acidic amino acids such as glutamic acid and aspartic acid in gluten and zein would give large amount of carboxyl groups effective for the apatite nucleation.

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Comparison of Apatite Formation on Polyamide Films Containing Carboxyl and Sulfonic Groups in a Solution Mimicking Body Fluid

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.309-311.477 ◽

2006 ◽

Vol 309-311 ◽

pp. 477-480

Author(s):

Chikara Ohtsuki ◽

Takahiro Kawai ◽

Masanobu Kamitakahara ◽

Masao Tanihara ◽

Toshiki Miyazaki ◽

...

Keyword(s):

Mechanical Properties ◽

Crystal Growth ◽

Simulated Body Fluid ◽

Calcium Ions ◽

Body Fluid ◽

Functional Group ◽

Carboxyl Groups ◽

Apatite Formation ◽

Ion Concentrations ◽

Polyamide Film

Apatite formation on polyamide films containing either carboxyl or sulfonic groups was compared in 1.5SBF, whose ion concentrations are 1.5 times those of a simulated body fluid (SBF). The sulfonic groups induced the apatite nucleation earlier than the carboxyl groups. In contrast, the rate of crystal growth depended not on the kind of functional group, but on the degree of supersaturation of the surrounding solution. The more ready association of sulfonic groups with calcium ions may lead to earlier apatite nucleation than that of carboxyl groups. Adhesive strength of the apatite layer to polyamide film containing sulfonic groups was significantly lower than that with carboxyl groups depending on the chemical interactions as well as on the mechanical properties of the polyamide film.

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Apatite-Forming Ability of Polyglutamic Acid Gel in Simulated Body Fluid: Effect of Cross-Linking Agent

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.330-332.683 ◽

2007 ◽

Vol 330-332 ◽

pp. 683-686 ◽

Cited By ~ 3

Author(s):

Atsushi Sugino ◽

Toshiki Miyazaki ◽

Chikara Ohtsuki

Keyword(s):

Simulated Body Fluid ◽

Heterogeneous Nucleation ◽

Body Fluid ◽

Organic Polymer ◽

Carboxyl Groups ◽

Cross Linking ◽

Apatite Formation ◽

Organic Substrates ◽

Polyglutamic Acid ◽

Acid Gel

Development of the organic-inorganic hybrids composed of apatite crystals and organic polymer is expected to be an attractive material that has mechanical properties similar to natural bone as well as bone-bonding ability, i.e. bioactivity. It is reported that the carboxyl groups (-COOH) on the surfaces of the organic substrates act as a catalyst for induction of heterogeneous nucleation of apatite. The present authors previously showed that the apatite was successfully deposited on the polyglutamic acid gels containing abundant carboxyl groups through the biomimetic process, when they were priorly treated with calcium chloride solution. In this study, we fabricated the polyglutamic acid gels with different degree of cross-linking. Effect of the cross-linking on their ability of the apatite formation was examined in simulated body fluid (SBF). It was suggested that the apatite deposition on the polyglutamic acid gels is governed not only by the amount of –COOH that induces the heterogeneous nucleation of the apatite, but also by swelling property that controls local increase in degree of supersaturation with respect to the apatite.

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A Comparative Study Between Dynamic and Static Simulated Body Fluid Methods

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.309-311.271 ◽

2006 ◽

Vol 309-311 ◽

pp. 271-274 ◽

Cited By ~ 1

Author(s):

Ji Yong Chen ◽

You Rong Duan ◽

Chun Lin Deng ◽

Qi Yi Zhang ◽

Xing Dong Zhang

Keyword(s):

Simulated Body Fluid ◽

Body Fluid ◽

Good Method ◽

Nucleation And Growth ◽

Ion Concentration ◽

Osseous Tissue ◽

Key Factors ◽

Good Agreement

In vitro method has often been used in the biodegradation/bioactivity evaluation of bioactive ceramics for its convenience and saving in time and outlay. The simulated body fluid (SBF) suggested by Kokubo was a good simulation of the osteoproduction environment in osseous tissue and has been proved to be a good method to study the bioactivity of biomaterials and the mechanism of bone bonding. But SBF is not a suitable method to research the osteoinduction of biomaterials. The results from SBF were not consistent with that from in vivo in muscle. The local ion concentration is the key factors to affect the nucleation and growth of apatite. In muscle the effect of body fluid flowing on local ion concentration cannot be ignored. A dynamic SBF suggested by these authors of this paper not only simulated the ion concentration of body fluid, but also simulated the effect of body fluid flowing on the local ion concentration near the surface or in biomaterials in muscle. The results from the dynamic SBF were in good agreement with that of the implantation experiments in muscle. The results from dynamic SBF showed that apatite only formed on the walls of macropores of the porous CaP, no apatite formed on the surface of both dense and porous CaP. The new bone only formed on the walls of macropores of porous CaP implanted in muscles, no apatite or osseous tissue could be found on the surfaces of both porous and dense CaP. The dynamic SBF preferably simulated the osteoinduction environment in non-osseous tissue and can be used in osteoinductivity evaluation of bioceramics.

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Surface functional group dependence on apatite formation on self-assembled monolayers in a simulated body fluid

Journal of Biomedical Materials Research ◽

10.1002/(sici)1097-4636(19970305)34:3<305::aid-jbm5>3.0.co;2-o ◽

1997 ◽

Vol 34 (3) ◽

pp. 305-315 ◽

Cited By ~ 436

Author(s):

Masami Tanahashi ◽

Takehisa Matsuda

Keyword(s):

Simulated Body Fluid ◽

Body Fluid ◽

Functional Group ◽

Self Assembled Monolayers ◽

Surface Functional Group ◽

Apatite Formation ◽

Assembled Monolayers ◽

Self Assembled

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Effect of Post-Treatment on Dissolution and Biomineralization on Surface of ha Coatings in Simulated Body Fluid (SBF)

MRS Proceedings ◽

10.1557/proc-599-55 ◽

1999 ◽

Vol 599 ◽

Cited By ~ 3

Author(s):

Jiyong Chen ◽

Jie Weng ◽

Qiyi Zhang ◽

Jiaming Feng ◽

Yang Cao ◽

...

Keyword(s):

Water Vapor ◽

Simulated Body Fluid ◽

Amorphous Phase ◽

Body Fluid ◽

Nucleation And Growth ◽

Post Treatment ◽

Tris Buffer

AbstractThe HA coatings were heated separately in vacuum, air and water vapor. The dissolution of the HA coatings was investigated by immersion in Tris buffer and SBF The dissolubility of HA coatings in the solutions decreased in this order: as-received, heated in vacuum, in air and in water vapor. The nucleation of bone-like apatite on the surfaces of HA coatings after immersing a period of 11 days in SBF was observed by SEM. The microenvironment with a sufficient supersaturation of Ca and P ions was crucial for the nucleation and growth of apatite in SBF. The dissolution of amorphous phase in coatings played an important part in establishing the supersaturation of Ca and P ions.

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