General Trends in the Desolvation Behavior of Calcium Salts

Abstract

Several factors influence the desolvation behavior of calcium salts. We believe the flexibility of the benzene rings in CaKTN, CaFEN, CaMEF and CaTOLF was important for these products to become mesomorphous when they loose their crystalline water; meanwhile, CaDIF where the two benzene rings are coplanar remained crystalline when heated. Additionally, the existence of water channels and the hydrogen bonding networks in the crystals is hypothesized to play an important role in the desolvation behavior of these materials.

Solid-State Characterization of Amorphous and Mesomorphous Calcium Ketoprofen

“…Liquid crystals are reported to have different physical properties and stability profiles than their crystalline parents or their amorphous counterparts 8, 9, 30. However, only a few published studies have attempted to explain these properties or to correlate them with the molecular‐level differences between these three phases.…”

“…In previous work in our laboratory we studied the behavior of several calcium salts upon dehydration and identified three general trends in the desolvation behavior of these calcium salts. While some calcium salts remained crystalline or partially crystalline upon desolvation8 several calcium salts became thermotropic mesophases 8, 9…”

Improvement of the water solubility of tolfenamic acid by new multiple-component crystals produced by mechanochemical methods

“…23 The strength of this interaction most likely explains the poor water solubility of HTA. Although one example of a HTA co-crystal, 24 five metal-complexes 25 and a calcium salt are reported in literature, 26 the (8) C (100 MHz) CPMAS spectra with main the assignments of HTA Form I and II, NaTA·0.5H2O, NaTA·HTA·H2O/NaHCO3, 80 NaTA·HTA·0.5NaAc·2H2O, NaTA HT Form and IMH·TA·HTA recorded at 12 kHz.…”

Polymorphism and Solvatomorphism 2006

“…171 Crystallographic methods were used to deduce trends in the desolvation behavior of a series of calcium salts of various drug substances. 172 The crystallization of lyophilized lactose and lactose-salt mixtures in environments having relative humidities in the range of 55-76% has been studied using a number of techniques in order to better understand the transient phases and stresses that are associated with the rapid onset of crystallization. 173 In another study, synchrotron X-ray diffractometry has been used to detect solute crystallization in frozen sodium phosphate buffer solutions.…”