Polymorph and Orientation Controls of Calcium Carbonate Crystals Achieved by Organic Matrices

Sato, Kimiyasu; Kumagai, Yuri; Kogure, Toshihiro; Tanaka, Junzo

doi:10.2109/jcersj.114.754

Cited by 10 publications

(16 citation statements)

References 27 publications

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“…Changes in shell architecture may be a primary control of Sr incorporation. The organic matrix of bivalves exerts control over the nucleation of the crystal with the matrix acting as nucleation surface and predefined mold, determining shape, size, and orientation of the crystals as well as the polymorph [ Belcher et al , 1996; Falini et al , 1996; Mann and Ozin , 2003; De Yoreo and Dove , 2004; Sato et al , 2006]. Changes in crystal growth and propagation may affect the partitioning and thus the Sr/Ca concentrations found within A. islandica .…”

Section: Discussionmentioning

confidence: 99%

Strontium distribution in the shell of the aragonite bivalve Arctica islandica

Foster

Allison

Finch

et al. 2009

Geochem Geophys Geosyst

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[1] The behavior of Sr in the aragonite shells of the bivalve Arctica islandica has been explored to determine its potential for high-resolution environmental reconstruction. The structural state of Sr in the shell was investigated using X ray absorption fine structure (XAFS) and Sr/Ca variations across the prismatic layer in the umbo and outer shell were determined by secondary ionization mass spectrometry (SIMS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) respectively. XAFS data suggest that Sr randomly substitutes for Ca within the shell aragonite. Sr/Ca in both the umbo and the outer shell exhibits significant seasonal variation but does not correlate with seawater temperature. Sr/Ca varies significantly between parallel transects across the same annual bands. Sr concentrations are highest in transects along the maximum growth axis of the outer shell but lowest in these transects in the umbo. Scanning electron microscopy indicates changes in crystal morphology both within and between transects. We do not, however, observe a clear relationship between shell growth rate and Sr/Ca. Fluctuations in Sr/Ca are most likely to be controlled by a complex interaction of biological and kinetic processes.

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Section: Discussionmentioning

confidence: 99%

Strontium distribution in the shell of the aragonite bivalve Arctica islandica

Foster

Allison

Finch

et al. 2009

Geochem Geophys Geosyst

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“…On the other hand, soluble organic matrices in solution control the mass transfer and reduce the rate or delay the onset of precipitation of inorganic crystals, and soluble organic matrices adsorbed on the surface of substrates define the location and number of nucleation sites, determine the orientation of the crystal growth and polymorph type, and act as templates for the final morphology of the inorganic materials. [1][2][3][4][5][6][7][8][9][10][11][12][13] In other words, soluble organic matrices have opposite functions, depending upon whether they are in solution or adsorb onto surfaces. Hence, for biomimetic materials processing it is important to know how the organic additives influence the crystallization process.…”

Section: Introductionmentioning

confidence: 99%

Controlled Crystallization of Calcite Under Surface Electric Field Due to Polarized Hydroxyapatite Ceramics

Wada¹,

Tanaka²,

Nakamura³

et al. 2009

Journal of the American Ceramic Society

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We examined effects of surface electric fields for the crystallization of calcite on polarized hydroxyapatite ceramics with and without polyacrylic acid (PAA) as soluble additive. Both on negatively and positively charged surfaces without PAA, the only precipitates were rhombohedra calcite crystals with the face of the {10.4} plane favorably oriented parallel to the surfaces. This oriented growth was explained by the nucleation theory in the presence of an external electric field. However, the addition of PAA drastically changed the situation of the calcite crystals, i.e., the crystallites were the hemispheric aggregates of calcite needles with a facetted rhombohedral {10.4} end face and flat island‐shaped aggregates of ones with a rough (00.1) end face having a triangular shape. The calcite needles grew along the crystallographic [00.1] axis. This oriented growth was explained by epitaxy on the PAA–Ca2+ complexes adsorbing on the surfaces. The morphology of the PAA–Ca2+ complex assemblies adsorbing on the surfaces before the calcite nucleation was an important factor to control the structure of calcite aggregates formed following. This morphology was controlled by properties of the surface electric field and the spatial distribution of the negatively and positively charged sites in the PAA–Ca2+ complexes.

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“…Spectral repeats were taken of three sub-samples and averaged to produce the final FT-IR spectra representative of each sample. 57 Fe Mössbauer spectroscopy was used to investigate the oxidation state and coordination environment of iron within surface scrapings from a sample of ordinary Portland cement, and the cement samples from the abiotic and biogenic treatments. Mössbauer spectra were collected at 293 K using a constant acceleration spectrometer with a 25 mCi 57 Co source in a Rh matrix.…”

Section: Composition and Speciationmentioning

confidence: 99%

“…57 Fe Mössbauer spectroscopy was used to investigate the oxidation state and coordination environment of iron within surface scrapings from a sample of ordinary Portland cement, and the cement samples from the abiotic and biogenic treatments. Mössbauer spectra were collected at 293 K using a constant acceleration spectrometer with a 25 mCi 57 Co source in a Rh matrix. Absorbers were prepared from ground samples mixed with graphite powder to ensure a Mössbauer thickness t<1.…”

Section: Composition and Speciationmentioning

confidence: 99%