Influence of carbonation on the low-temperature consolidation by Spark Plasma Sintering of carbonated calcium phosphate bioceramics

Abstract

Influence of carbonation on the low-temperature consolidation by SparkPlasma Sintering of carbonated calcium phosphate bioceramics. (2020) Ceramics International, 46 (5). 5799-5810.

Tailoring the structure and self-activated photoluminescence of carbonated amorphous calcium phosphate nanoparticles for bioimaging applications

“…19 Moreover, the w CO 3 and the resulting Ca/P values due to CO 3 2− incorporation align closely with those documented in the literature, 19,51 confirming the feasibility of the FTIR-based quantification methodology for ACP NPs, as corroborated by elemental analysis (see Table S2, ESI†) and elsewhere. 52…”

“…19 Moreover, the wCO 3 and the resulting Ca/P values due to CO 3 2À incorporation align closely with those documented in the literature, 19,51 confirming the feasibility of the FTIR-based quantification methodology for ACP NPs, as corroborated by elemental analysis (see Table S2, ESI †) and elsewhere. 52 In the subsequent step, TGA was performed on all assynthesized NPs to quantify their structural water contents, wH 2 O(S). By examining the TGA curves and their first derivative (DTG), illustrated in Fig.…”

Apatite/Chitosan Composites Formed by Cold Sintering for Drug Delivery and Bone Tissue Engineering Applications

“…As reported in Table 2 , the Ca/P ratio of HAp is 1.38 well below the stoichiometric Ca/P of 1.67, indicating a calcium-deficient apatite and supporting the hypothesis of a non-stoichiometric, multi-ion-substituted apatite with limited crystallinity. In some previous studies, Ortali et al [ 101 ] reported a Ca/P ratio of ~1.35 for a calcium-deficient HAp and of ~1.33 for a biomimetic nanocrystalline apatite, whereas Drouet et al [ 20 ] observed a gradual increase in the Ca/P ratio of nanocrystalline apatite from 1.30 to 1.48, depending on the maturation time, which was up to 20 days. The Ca/P ratio in the composites further decreases to 1.26 for HAp10Chit and to 1.27 for HAp10ChitSrRAN.…”

“…The non-stoichiometry of the produced apatite powder was further investigated by peak decomposition of the ν 4 PO 4 (800–400 cm −1 ) and ν 2 CO 3 (900–800 cm −1 ) infrared spectral domains. Indeed, in the case of biomimetic apatite, these spectral domains are characterised by the presence of apatitic and non-apatitic phosphate and carbonate environments [ 21 , 74 , 84 , 101 ]: the apatitic ones include ions in the apatite normal crystallographic sites, while the non-apatitic ions are not located within the apatite lattice [ 20 ]. As a matter of fact, the non-apatitic (or labile) environments in bone-like apatite are associated with a thin hydrated layer surrounding the nanocrystals, where exchangeable ions (mostly divalent Ca 2+ , HPO 4 2− and CO 3 2− ) are present [ 21 , 74 , 84 , 101 ].…”

“…Indeed, in the case of biomimetic apatite, these spectral domains are characterised by the presence of apatitic and non-apatitic phosphate and carbonate environments [ 21 , 74 , 84 , 101 ]: the apatitic ones include ions in the apatite normal crystallographic sites, while the non-apatitic ions are not located within the apatite lattice [ 20 ]. As a matter of fact, the non-apatitic (or labile) environments in bone-like apatite are associated with a thin hydrated layer surrounding the nanocrystals, where exchangeable ions (mostly divalent Ca 2+ , HPO 4 2− and CO 3 2− ) are present [ 21 , 74 , 84 , 101 ]. Due to the metastability of bone-like apatite, upon maturation and/or heat treatment, the hydrated layer could gradually disappear and the labile ions could be incorporated into the bulk apatite domains, thus resulting in a more stable apatite with a higher crystallinity and stoichiometry closer to 1.67 [ 13 ].…”