Divalent Mn in calcium hydroxyapatite by pulse laser deposition

Mayer, I.; Petö, G.; Karacs, Albert; Molnár, G.; Popov, Inna

doi:10.1016/j.jinorgbio.2010.06.009

Cited by 10 publications

(6 citation statements)

References 20 publications

(21 reference statements)

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“…The main 2p 3/2 peak can be assigned to the positions of MnO at 640.3-641.4 eV or Mn 2 O 3 at 641.5-641.7 eV, which correspond to Mn 2+ or Mn 3+ valance states respectively. 48 However, MnO has a satellite feature (∼645 eV) for 2p 3/2 and (∼657 eV) for 2p 1/2 which is not present for either Mn 2 O 3 or MnO 2 , 49,50 so confirming the presence of Mn 2+ ions in the synthesized samples. As the difference of binding energy of different Mn ions are very small therefore low concentration of Mn 3+ can be excluded and divalent Mn ions should be dominating.…”

Section: Xps Analysismentioning

confidence: 80%

Mechanical preparation of nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp): effect of Mn doping on microstructure

et al. 2015

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Nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp) powder has been synthesized by mechanical alloying of a stoichiometric mixture of CaCO3, CaHPO4·2H2O and MnO powder for 10 h at room temperature under open air. The A-type carbonation in HAp (substitution of CO3(2-) for OH(-)) is confirmed by FTIR analysis. Microstructure characterization in terms of lattice imperfections and phase quantification of ball milled samples are made by analyzing XRD patterns employing the Rietveld structure refinement method. Rietveld analysis of XRD patterns recorded from Mn-doped HAp samples has been used to locate Mn(2+) cations in HAp. The Ca2 vacancy site is found to be more favorable for Mn substitution. Microstructure characterization by HRTEM corroborates the findings of the X-ray analysis where the presence of a significant amount of amorphous phase of HAp analogous to indigenous bone mineral is clearly found. MTT assay shows sufficiently high percentage cell viability confirming the cytocompatibility of the sample.

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Section: Xps Analysismentioning

confidence: 80%

Mechanical preparation of nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp): effect of Mn doping on microstructure

et al. 2015

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“…It is worth noting that substitution with Mn 2+ ions was not trivial and ran with low efficiency. Recent works on the synthesis of hydroxyapatites enriched in manganese indicate that the substitution takes place within a limited range (up to 10 mol%) [22,24]. In addition, the thermal treatment of Mn-HA causes the decomposition of material at a fairly low temperature (600 °C) [21,24].…”

Section: Resultsmentioning

confidence: 99%

“…Other mechanisms of manganese’s beneficial effects on bone tissue metabolism include osteocalcin stimulation, increased alkaline phosphatase activity and collagen type I production [13,14,19]. Syntheses of hydroxyapatites substituted with various amounts of manganese were carried out, from trace amounts (a few ppm) to 11.9 wt% [14,16,19,20,21,22,23,24]. However, it is important to note that in vitro studies on osteoblast cells showed significantly better results for lower manganese contents [16,19], while a Mn content of 1 wt% was regarded as high and caused drastically lower cell viability [24].…”

Section: Introductionmentioning

confidence: 99%

Dual Doping of Silicon and Manganese in Hydroxyapatites: Physicochemical Properties and Preliminary Biological Studies

2019

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Silicated hydroxyapatite powders enriched with small amounts of manganese (Mn2+) cations were synthesized via two different methods: precipitation in aqueous solution and the solid-state method. The source of Mn2+ ions was manganese acetate, while silicon was incorporated using two different reagents: silicon acetate and sodium metasilicate. Powder X-ray diffraction (PXRD) analysis showed that the powders obtained via the precipitation method consisted of single-phase nanocrystalline hydroxyapatite. In contrast, samples obtained via the solid-state method were heterogenous and contaminated with other phases, (i.e., calcium oxide, calcium hydroxide, and silicocarnotite) arising during thermal treatment. The transmission electron microscope (TEM) images showed powders obtained via the precipitation method were nanosized and elongated, while solid-state synthesis produced spherical microcrystals. The phase identification was complemented by Fourier transform infrared spectroscopy (FTIR). An in-depth analysis via solid-state nuclear magnetic resonance (ssNMR) was carried out, using phosphorus 31P single-pulse Bloch decay (BD) (31P BD) and cross-polarization (CP) experiments from protons to silicon-29 nuclei (1H → 29Si CP). The elemental measurements carried out using wavelength-dispersive X-ray fluorescence (WD-XRF) showed that the efficiency of introducing manganese and silicon ions was between 45% and 95%, depending on the synthesis method and the reagents. Preliminary biological tests on the bacteria Allivibrio fisheri (Microtox®) and the protozoan Spirostomum ambiguum (Spirotox) showed no toxic effect in any of the samples. The obtained materials may find potential application in regenerative medicine, bone implantology, and orthopedics as bone substitutes or implant coatings.

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“…It has also been reported that calcium hydroxyapatite (HA) doped with Mn (Mn‐HA) favors osteoblasts activity and proliferation . Therefore, Mn‐HA exhibits better osseointegration than HA and is preferable for coating of titanium implants . The incorporation of small amounts of Mn to HA also has a beneficial influence on the process of sintering and densification of bioceramics, thus improving their mechanical parameters …”

Section: Introductionmentioning

confidence: 99%

Solid‐State NMR Study of Mn²⁺ for Ca²⁺ Substitution in Thermally Processed Hydroxyapatites

et al. 2014

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In the present study calcium hydroxyapatites enriched at 0.08 wt% in Mn 2+ ions (Mn-HA) and their unsubstituted forms (HA) were synthesized using the same standard wet chemical route. Mn-HA and HA were both calcined at 800°C to give Mn-HAc and HAc, respectively or sintered at 1250°C, to give Mn-HAs and HAs, respectively. The influence of the heat treatment on physicochemical properties of Mn-HA was investigated using powder X-ray diffraction (PXRD), scanning, and transmission electron microscopy (SEM and TEM), and solid-state nuclear magnetic resonance (ssNMR). Mn-HAc and Mn-HAs were compared to each other and to HAc and HAs, respectively. Assignment of the proton ssNMR peaks from high-temperature-treated apatites has been revised. It was found that Mn-HAc and HAc were nanocrystalline, while Mn-HAs and HAs comprised micrometer sized, partially fused particles (SEM and TEM). PXRD and ssNMR demonstrated that the incorporation of Mn 2+ into the crystal lattice of hydroxyapatite significantly facilitates its dehydroxylation and decomposition to oxyhydroxyapatite during calcination at 800°C, and induces its transformation to tetracalcium phosphate (TTCP) and alpha-tricalcium phosphate (a-TCP) at 1250°C. Contamination by CaO has also been detected. The 1 H? 31 P NMR cross-polarization experiments have indicated that the Mn 2+ ions preferentially occupied the Ca(I) position in the crystallographic unit cell of Mn-HAc. In Mn-HAs, the Mn 2+ ions were evenly distributed between the Ca(I) and Ca (II) positions.

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Divalent Mn in calcium hydroxyapatite by pulse laser deposition

Cited by 10 publications

References 20 publications

Mechanical preparation of nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp): effect of Mn doping on microstructure

Mechanical preparation of nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp): effect of Mn doping on microstructure

Dual Doping of Silicon and Manganese in Hydroxyapatites: Physicochemical Properties and Preliminary Biological Studies

Solid‐State NMR Study of Mn²⁺ for Ca²⁺ Substitution in Thermally Processed Hydroxyapatites

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Divalent Mn in calcium hydroxyapatite by pulse laser deposition

Cited by 10 publications

References 20 publications

Mechanical preparation of nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp): effect of Mn doping on microstructure

Mechanical preparation of nanocrystalline biocompatible single-phase Mn-doped A-type carbonated hydroxyapatite (A-cHAp): effect of Mn doping on microstructure

Dual Doping of Silicon and Manganese in Hydroxyapatites: Physicochemical Properties and Preliminary Biological Studies

Solid‐State NMR Study of Mn2+ for Ca2+ Substitution in Thermally Processed Hydroxyapatites

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Solid‐State NMR Study of Mn²⁺ for Ca²⁺ Substitution in Thermally Processed Hydroxyapatites