Synthesis of Silicon- and Carbonate-doped Biomimetic Hydroxyapatite in the Presence of Citrate Ions and its Physicochemical, Bioactivity Properties

Abstract

The present study investigated the phase composition, the structural, morphological, and bioactivity properties of silicon- and carbonate-doped biomimetic hydroxyapatite synthesized by precipitation from aqueous solutions in the presence of different amounts of citrate ions. The X-ray diffraction and Fourier transform infrared spectroscopy analyses confirmed that all the samples exhibited single-phase. Base on the results of the morphological study, all the obtained samples consisted of porous agglomerated particles made up of tiny crystallites in the nanometer range. The change in structural order, as well as the decrease in particle size and degree of crystallinity result from the presence of citrate ions were revealed by X-ray diffraction, dynamic light scattering, and scanning electron microscopy analyses. Bioactivity properties of samples were studied by analyzing their bioresorbability in physiological saline (ω (NaCl) = 0.9%) and evaluating their solubility in SBF solution after a certain period of soaking time. The amount of the released Ca2+ ions was found to increase with the increasing concentration of citrate ions introduced in the synthesis process. The better solubility of material with the presence of citrate ions was beneficial in the growth of apatite on its surface that made produced material more biocompatible.

Development, In-Vitro Characterization and In-Vivo Osteoinductive Efficacy of a Novel Biomimetically-Precipitated Nanocrystalline Calcium Phosphate With Internally-Incorporated Bone Morphogenetic Protein-2

“…The weak bands of BpNcCaPs at 1,415-1,419 cm −1 and 866-872 cm −1 might be assigned to carbonate. Carbonates are constituents of bone structures, whose presence may improve the bioactivity of HA (Vallet-Regi and González-Calbet, 2004;Hoang et al, 2020). According to the literature (Fahami et al, 2012;Ignjatović et al, 2019;Edén, 2021), the functional groups generally observed in the FTIR spectra of CaP-based materials are PO 4 3-, OH − and CO 3 2groups in the range 4000-300 cm −1 .…”

Effect of Molar Ratios in the Crystallochemical Structure of Biomimetic Nanostructured Hydroxyapatite on the Characteristics of the Product

“…It was also reported [21,22] that the addition of citrate ions (Cit 3-) into the reaction medium during HAP synthesis changes the structural and morphological characteristics of the product materials. Citrate ions participating in biological cycles play an important role in bone tissue resorption and bioapatite formation, for example, during the nanoscale stabilization of HAP crystallites in bone [23][24][25][26].…”