Is there a relationship between solubility and resorbability of different calcium phosphate phases in vitro ?

Abstract

BACKGROUND Does chemistry govern biology or it is the other way around - that is a broad connotation of the question that this study attempted to answer. METHOD Comparison was made between the solubility and osteoclastic resorbability of four fundamentally different monophasic CP powders with monodisperse particle size distributions: alkaline hydroxyapatite (HAP), acidic monetite (DCP), β-calcium pyrophosphate (CPP), and amorphous CP (ACP). RESULTS With the exception of CPP, the difference in solubility between different calcium phosphate (CP) phases became neither mitigated nor reversed, but augmented in the resorptive osteoclastic milieu. Thus, DCP, a phase with the highest solubility, was also resorbed more intensely than any other CP phase, whereas HAP, a phase with the lowest solubility, was resorbed least. CPP becomes retained inside the cells for the longest period of time, indicating hindered digestion of only this particular type of CP. Osteoclastogenesis was mildly hindered in the presence of HAP, ACP and DCP, but not in the presence of CPP. The most viable CP powder with respect to the mitochondrial succinic dehydrogenase activity was the one present in natural biological bone tissues: HAP. CONCLUSION Chemistry in this case does have a direct effect on biology. Biology neither overrides nor reverses the chemical propensities of inorganics with which it interacts, but rather augments and takes a direct advantage of them. SIGNIFICANCE These findings set the fundamental basis for designing the chemical makeup of CP and other biosoluble components of tissue engineering constructs for their most optimal resorption and tissue regeneration response.

Nanofibrous ε-polycaprolactone scaffolds containing Ag-doped magnetite nanoparticles: Physicochemical characterization and biological testing for wound dressing applications in vitro and in vivo

“…Aside from the more abundant presence of particles forming as precipitates from the cell culture medium and adhering onto the scaffold; all compositions displayed prominent cell attachment. With the potential formation of bioactive calcium phosphate nanoparticles, the cell culture medium is supersaturated [ 88 ]. It cannot be excluded that their adherence onto the nanofibers presents one of the driving forces for the subsequent or simultaneous attachment of cells as well.…”

Attachment and spatial organisation of human mesenchymal stem cells on poly(ethylene glycol) hydrogels

“…Nonetheless, the biological activity and stability of CaP is highly dependent on the solubility of CaP minerals [155]. While the solubility of CaP is highly dependent on the pH of the environment [156], the high solubility of ACP makes it more readily available to cells in comparison to minerals with lower solubility [157]. This feature of ACP serves as the basis for incorporating CaP with high solubility into hydrogels to serve as a building block for a mineralised ECM.…”

Calcium Phosphate as a Key Material for Socially Responsible Tissue Engineering

“…Then, although the solubility product is indeed a determinant of bioresorbability when it comes to calcium orthophosphates [ 159 ], degradation of CAPs in vivo —like that of most ceramics except the biosoluble ones—and the consequent release of the payload take place through cell/material interaction (lactic acid release, phagocytosis, etc. ) rather than through hydrolysis and/or physical, porosity-controlled release as in the case of polymers.…”