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Intercalation of Sea Urchin Proteins in Calcite: Study of a Crystalline Composite Material

Berman, Amir, Addadi, Lia, Kvick, Åke, Leiserowitz, Leslie, Nelson, Mitch, Weiner, Stephen·1990·Science

Abstract

Sea urchin skeletal elements are composed of single crystals of calcite. Unlike their synthetic counterparts, these crystals do not have well-developed cleavage and are consequently much more resistant to fracture. This phenomenon is due in part to the presence of acidic glycoproteins occluded within the crystals. By means of x-ray diffraction with synchrotron radiation, it is shown that the presence of the protein in synthetic calcite only slightly decreases the coherence length but significantly increases the angular spread of perfect domains of the crystals. In biogenic calcite, the coherence length is 1/3 to 1/4 as much as that in synthetic calcite and the angular spread is 20 to 50 times as wide. It is proposed that the presence of macromolecules concentrated at mosaic boundaries that are oblique to cleavage planes is responsible for the change in fracture properties. These results may be important in the material sciences, because of the unusual nature of this material, namely, a composite based on the controlled intercalation of macromolecules inside single-crystal lattices.

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Metadata

Authors
Berman, A., Addadi, L., Kvick, Å., Leiserowitz, L., Nelson, M., & Weiner, S.
Venue
Science
Published
1990-11-02
Volume
250
Issue
4981
Pages
664-667
ISSN
  • 0036-8075 (ISSN-L)
  • 1095-9203
OpenAlex
W1979883063
Cited by
328
References
0
FWCI
7.03
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Intercalation of Sea Urchin Proteins in Calcite: Study of a Crystalline Composite Material. https://app.cochat.ai/papers/10.1126/science.250.4981.664
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Berman, A., Addadi, L., Kvick, Å., Leiserowitz, L., Nelson, M., & Weiner, S. (1990). Intercalation of Sea Urchin Proteins in Calcite: Study of a Crystalline Composite Material. Science. https://doi.org/10.1126/science.250.4981.664

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