A Dendritic Amphiphile for Efficient Control of Biomimetic Calcium Phosphate Mineralization

Abstract

The phase behavior of a dendritic amphiphile containing a Newkome-type dendron as the hydrophilic moiety and a cholesterol unit as the hydrophobic segment is investigated at the air-liquid interface. The amphiphile forms stable monomolecular films at the air-liquid interface on different subphases. Furthermore, the mineralization of calcium phosphate beneath the monolayer at different calcium and phosphate concentrations versus mineralization time shows that at low calcium and phosphate concentrations needles form, whereas flakes and spheres dominate at higher concentrations. Energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and electron diffraction confirm the formation of calcium phosphate. High-resolution transmission electron microscopy and electron diffraction confirm the predominant formation of octacalcium phosphate and hydroxyapatite. The data also indicate that the final products form via a complex multistep reaction, including an association step, where nano-needles aggregate into larger flake-like objects.

Anionic Polymer Brushes for Biomimetic Calcium Phosphate Mineralization—A Surface with Application Potential in Biomaterials

“…X-ray diffraction (XRD) only produces very noisy patterns with low count rates that cannot be analyzed further. This is consistent with earlier results on similar materials [4,5,7,8] and can be assigned to the often very low order in these materials in addition to very low sample amounts.…”

“…Often, (biological) mineral formation and dissolution occur at an interface. This has triggered a number of studies on the effects of surfaces and interfaces on mineral deposition, notably calcium phosphate (CP) [2,3,4,5,6,7,8].…”

EDTA and NTA Effectively Tune the Mineralization of Calcium Phosphate from Bulk Aqueous Solution

“…For example, it is possible that the transformation of DCPD to HAP at higher additive concentration is favored at higher pH because at higher pH the additives are less protonated. As the transition from DCPD to HAP releases protons [24,49,88], the higher number of charged carboxylate groups may favor the transformation by taking up some of the released protons, similar to some other examples [37,38,39,89,90]. In contrast, at lower pH, the additives show a higher degree of protonation and thus the DCPD/HAP transformation is slower [35].…”

Two-Dimensional Immiscible Domain of Cholesterol in the Lipid Bilayer Membrane Promotes Early Stage Calcification by Inducing Oriented Nucleation of Hydroxyapatite

“…3−5 Whether it is normal or abnormal, the crystallization and deposition of inorganic minerals during the calcification process are thought to be mediated by the in vivo interface. 6,7 To date, many biomimetic monolayers, e.g., dipalmitoylphosphatidylcholine (DPPC), 8,9 cholesteryl amphiphiles, 10,11 and arachidic acid, 12 have been evaluated in the in vivo crystallization process of calcium phosphate (CP). However, the induction interface still remains controversial, especially for CP-induced calcification that occurs in atherosclerosis.…”

“…Calcification is an essential biomineralization process in which calcium accumulated in body tissues, causing the tissues to harden. , Normal calcification leads to the formation of bones and teeth, while unexpected calcification is associated with a variety of pathological conditions such as arteriosclerosis, osteoporosis, and kidney stones. − Whether it is normal or abnormal, the crystallization and deposition of inorganic minerals during the calcification process are thought to be mediated by the in vivo interface. , To date, many biomimetic monolayers, e.g., dipalmitoylphosphatidylcholine (DPPC), , cholesteryl amphiphiles, , and arachidic acid, have been evaluated in the in vivo crystallization process of calcium phosphate (CP). However, the induction interface still remains controversial, especially for CP-induced calcification that occurs in atherosclerosis.…”