Dynamics of crystallization and dissolution of calcium orthophosphates at the near-molecular level

Abstract

Although extensive investigations of biogenic and geological calcium phosphate crystallization/dissolution and their phase transformations have been performed, the mechanisms of crystallization and dissolution of sparingly soluble calcium phosphates in geological settings have not been completely determined at the near-molecular level. In particular, an understanding of the physical-chemical processes at the earliest nucleation stage and the subsequent crystal surface dynamics in soil solutions is lacking. This review focuses on the earliest events in homo/heterogeneous nucleation from an initial supersaturated solution phase, the subsequent growth of calcium phosphate phases, and the relevant influences of the presence of additional inorganic and organic molecules in both geological and biological settings. These studies have implications for the understanding of the complex processes of calcium phosphate transformations in soils, and provide possible physical-chemical mechanisms for the biogeochemical behavior of phosphorus at the near-molecular level. calcium orthophosphates, crystallization, dissolution, AFM Citation:Wang L J, Lu J W, Xu F S, et al. Dynamics of crystallization and dissolution of calcium orthophosphates at the near-molecular level.

Conservation of weathered historic sandstone with biomimetic apatite

“…The characteristic diffraction peaks of hydroxyapatite can be easily distinguished in the XRD patterns (Figure 2b) of the interlocked structure. From these results, the composition of the interlocked structure is hydroxyapatite [37], the most stable phosphate in nature [38]. Analytical results obtained using the Jade program [39] indicate that the crystallinity of the hydroxyapatite crystals is 90.727%, which is consistent with the SAED results.…”

Calcium orthophosphate deposits: Preparation, properties and biomedical applications

“…As to the precipitation mechanisms of CaPO 4 from aqueous solutions, this process appears to be rather complicated and for the biologically relevant CaPO 4 (OCP, CDHA and HA) it occurs via formation of one or several intermediate and/or precursor phases, such as ACP, DCPD and/or OCP. The detailed description of the precipitation mechanisms is beyond the scope of current review; the interested readers are referred to the special literature on the topic [320][321][322].…”

Calcium orthophosphate coatings, films and layers

“…As to the precipitation mechanism of calcium orthophosphates from aqueous solutions, this process appears to be rather complicated; for the biologically relevant calcium orthophosphates (OCP, CDHA and HA), the crystallization process occurs via formation of one or several intermediate and/or precursor phases, such as ACP, DCPD and/or OCP. The detailed description of the precipitation mechanisms of various calcium orthophosphates is beyond the scope of current review; the interested readers are referred to the special literature on the topic (Wang and Nancollas 2008; Wang et al 2011). …”