Mechanical Properties of a Calcium Dietary Supplement, Calcium Fumarate Trihydrate

Inorg Chem. 2015 Dec 7;54(23):11186-92. doi: 10.1021/acs.inorgchem.5b01466. Epub 2015 Nov 20.

Abstract

The mechanical properties of calcium fumarate trihydrate, a 1D coordination polymer considered for use as a calcium source for food and beverage enrichment, have been determined via nanoindentation and high-pressure X-ray diffraction with single crystals. The nanoindentation studies reveal that the elastic modulus (16.7-33.4 GPa, depending on crystallographic orientation), hardness (1.05-1.36 GPa), yield stress (0.70-0.90 GPa), and creep behavior (0.8-5.8 nm/s) can be rationalized in view of the anisotropic crystal structure; factors include the directionality of the inorganic Ca-O-Ca chain and hydrogen bonding, as well as the orientation of the fumarate ligands. High-pressure single-crystal X-ray diffraction studies show a bulk modulus of ∼ 20 GPa, which is indicative of elastic recovery intermediate between small molecule drug crystals and inorganic pharmaceutical ingredients. The combined use of nanoindentation and high-pressure X-ray diffraction techniques provides a complementary experimental approach for probing the critical mechanical properties related to tableting of these dietary supplements.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anisotropy
  • Crystallography, X-Ray
  • Dietary Supplements*
  • Elasticity
  • Fumarates / chemistry*
  • Hardness
  • Hydrogen Bonding
  • Stress, Mechanical

Substances

  • Fumarates
  • calcium fumarate