Article
Multidisciplinary Sciences
Zofia Dubicka, Maciej J. Bojanowski, Jelle Bijma, Ulf Bickmeyer
Summary: Calcium carbonate minerals produced by marine organisms are important in the global carbon cycle and sedimentation, affecting climate by regulating atmospheric CO2 levels. Foraminifera are important single-celled marine organisms that have been producing calcite shells for over 300 million years. This study investigated the biocalcification process of foraminifera by studying Amphistegina lessonii, and found that their calcite shells are formed through deposition of intracellularly formed Mg-rich amorphous calcium carbonate particles, involved with the activity of endosymbiotic microalgae and seawater-derived endocytic vesicles.
Article
Multidisciplinary Sciences
Nuphar Bianco-Stein, Iryna Polishchuk, Arad Lang, Lotan Portal, Catherine Dejoie, Alexander Katsman, Boaz Pokroy
Summary: During biomineralization, organisms use high-Mg nanoparticles embedded in lower-Mg calcite matrices to enhance the mechanical properties of their skeletons. The formation of these nanoparticles is likely achieved through spinodal decomposition of an amorphous Mg-calcite precursor, and it is independent of the biological characteristics of the organisms but rather depends on their chemical composition and specific Mg content. This biostrategy significantly impacts the understanding of fracture resistance in biominerals.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Physical
Yi-Ming Ju, Fang Huang, Xin Ding, Li-Bo Mao, Shu-Hong Yu
Summary: This study investigates the mechanism of Mg2+ ion-regulated mineralization of CaCO3 by tracing Mg isotope fractionation. The different mineralization pathways of CaCO3 under different Mg2+ ion concentrations are clarified, and the detailed regulatory role of Mg2+ ions at different stages of mineralization is proposed. These results provide important insights for finely controlling the phase of crystalline products.
Article
Chemistry, Physical
Yi-Ming Ju, Fang Huang, Xin Ding, Li-Bo Mao, Shu-Hong Yu
Summary: This study clarifies the different mineralization pathways of CaCO3 under different Mg2+ ion concentrations by tracing Mg isotope fractionation. The detailed regulatory role of Mg2+ ions at different stages of mineralization is proposed.
Article
Engineering, Biomedical
Nuphar Bianco-Stein, Iryna Polishchuk, Arad Lang, Galit Atiya, Julie Villanova, Paul Zaslansky, Alexander Katsman, Boaz Pokroy
Summary: The calcareous alga Jania sp. exhibits a highly intricate structure with helical inner pores, and each cell wall nanocrystal comprises Mg-rich calcite nanoparticles demonstrating various crystallographic orientations. This unique structure assists in preventing fracture and enhancing the alga's fracture toughness, and the presence of Mg-rich nanoparticles is also observed in another species of coralline red algae, pointing to the generality of this phenomenon.
ACTA BIOMATERIALIA
(2021)
Article
Plant Sciences
Merinda C. Nash, Walter Adey, Adela S. Harvey
Summary: The study on mineral composition of Amphiroa species revealed high levels of VHMC and dolomite, which may provide competitive advantage in acidified seawater. Further research is needed to understand the metabolic controls on VHMC/dolomite mineral formation.
JOURNAL OF PHYCOLOGY
(2021)
Article
Chemistry, Physical
Heike Helmholz, Blessing Adejube, Berengere Luthringer-Feyerabend, Regine Willumeit-Romer
Summary: The study found that the presence of fetuin and calcium together can significantly decrease the degradation rate of pure magnesium. This could be due to the formation of a dense protein-degradation product protection barrier on the material surface, as well as the limitation of freely available calcium leading to decreased degradation.
Article
Materials Science, Multidisciplinary
Li-Mei Shang, Jun Jiang, Shu-Hong Yu
Summary: This study reports a facile method to synthesize corn-like Mg-calcite mesocrystals using only Ca2+ and Mg2+ from pure ACC. The resulting mesocrystals consist of many nanocubes with common crystallographic orientation, displaying excellent single crystal features. In the crystallization process, ACC nanospheres rapidly agglomerate into Mg-calcite corn-like mesocrystals through oriented attachment in a certain direction, shedding new light on the role of seawater in the formation of biological Mg-calcite.
SCIENCE CHINA-MATERIALS
(2021)
Article
Cell & Tissue Engineering
Maryam Rahmati, Sabine Stoetzel, Thaqif El Khassawna, Kamila Iskhahova, D. C. Florian Wieland, Berit Zeller Plumhoff, Havard Jostein Haugen
Summary: This study found that Magnesium-based degradable alloys have the potential to stimulate macrophage polarization in vivo, but no statistically significant differences were observed regarding biomineralization.
JOURNAL OF TISSUE ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Ouassef Nahi, Alexander N. Kulak, Shuheng Zhang, Xuefeng He, Zabeada Aslam, Martha A. Ilett, Ian J. Ford, Robert Darkins, Fiona C. Meldrum
Summary: This study demonstrates the remarkable control ability of cationic polyamines over the crystallization of calcium carbonate, promoting nucleation of aragonite at low concentrations and inhibiting its growth at high concentrations. The results reveal a mechanism of interaction between polyamines and magnesium ions that allows unprecedented control over aragonite formation.
Article
Geochemistry & Geophysics
Dorota Kolbuk, Philippe Dubois, Jaroslaw Stolarski, Przemyslaw Gorzelak
Summary: The Mg/Ca ratio in echinoderm skeletons is influenced by seawater chemistry, indicating that fossil echinoderms may provide a record of paleoseawater Mg2+/Ca2+. While sea stars were not significantly stressed by decreased seawater Mg2+/Ca2+, brittle stars were affected in growth and mortality. Reconstruction of paleoseawater Mg2+/Ca2+ from fossil echinoderms is limited by variations in Mg partition coefficients among different species.
Article
Nanoscience & Nanotechnology
Gukin Han, Yeonju Noh, Umer Masood Chaudry, Sung Hyuk Park, Kotiba Hamad, Tea-Sung Jun
Summary: The study found that Mg-0.5Ca alloy exhibits temperature-insensitive hardening behavior, while pronounced twinning activity was observed in pure Mg when deformed at low temperatures. The microstructure of Mg-0.5Ca helps reduce twinning behavior, resulting in its hardening behavior being temperature-dependent.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Engineering, Chemical
Alexandre Silva Guimaraes, Marcelo Borges Mansur
Summary: Selective solvent extraction of Mg and Ca from Ni-rich sulfate solutions was studied using different extractive systems. It was found that by adjusting the pH and concentration of the extractants, selective separation of Mg and Ca from Ni can be achieved.
MINERALS ENGINEERING
(2022)
Article
Geochemistry & Geophysics
Janou A. Koskamp, Sergio E. Ruiz Hernandez, Nora H. De Leeuw, Mariette Wolthers
Summary: Magnesium (Mg2+) has a complex non-linear impact on the surface properties, structure, and calcium adsorption energy of calcite, resulting in increased surface energy, constrained Ca2+ stability, and altered crystal structure. These effects contribute to the non-uniform dissolution process of magnesium-bearing calcites.
Article
Crystallography
Jasminka Kontrec, Nenad Tomasic, Nives Matijakovic Mlinaric, Damir Kralj, Branka Njegic Dzakula
Summary: This study investigates the impact of initial pH and stirring type on CaCO3 precipitation and phase composition, finding that higher pH favors the formation of calcite and mechanically stirred systems produce larger particles with higher content of calcite.
