In vitro surface biocompatibility of high-content silicon-substituted calcium phosphate ceramics

AbstractThe present work investigates surface biocompatibility of silicon-substituted calcium phosphate ceramics. Different silicon-substituted calcium phosphate ceramic bodies were prepared from co-precipitated powders by sintering at 1300°C. The in vitro bioactivity of the ceramics was assessed in simulated body fluid (SBF) at 37°C for periods up to 4 weeks. The changes in the surface morphology and composition were determined by scanning electron microscopy (SEM) coupled with electron probe microanalysis and energy dispersive spectrometer (EDX). Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to observe the change in ionic concentration of SBF after removal of the samples. The bioactivity of the ceramics increased with an increasing silicate ion substitution in a systematic way. The surface of ceramics with 2.23% silicon substitution was partially covered with apatite layer after one week, while ceramics with 8.1% silicon substitution were completely covered with apatite in the first week. The porous microstructure of high-concentration Si-substituted ceramics helps the dissolution of surface ions and the leaching process. This allows SBF to reach supersaturation in a short time and accelerate the deposition of apatite layer.

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Formation of Porous Apatite Layer during In Vitro Study of Hydroxyapatite-AW Based Glass Composites

Advances in Condensed Matter Physics ◽

10.1155/2015/158582 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 10

Author(s):

Pat Sooksaen ◽

Natyada Pengsuwan ◽

Sittipong Karawatthanaworrakul ◽

Surasak Pianpraditkul

Keyword(s):

Inductively Coupled Plasma ◽

Early Stage ◽

In Vitro Study ◽

Optical Emission ◽

Apatite Layer ◽

Vitro Study ◽

Glass Composites ◽

Inductively Coupled ◽

Sbf Solution

This research discussed the fabrication, characterization, and in vitro study of composites based on the mixture of hydroxyapatite powder and apatite-wollastonite (AW) based glass. AW based glass was prepared from the SiO2-CaO-MgO-P2O5-CaF2glass system. This study focuses on the effect of composition and sintering temperature that influences the properties of these composites. Microstructural study revealed the formation of apatite layer on the composite surfaces when immersed in simulated body fluid (SBF) solution at 37°C. Composites containing ≥50 wt% AW based glass showed good bioactivity after 7 days of immersion in the SBF. A porous calcium phosphate (potentially hydroxycarbonate apatite, HCA) layer formed at the SBF-composite interface and the layer became denser at longer soaking period, for periods ranging from 7 to 28 days. Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) analysis showed that early stage of soaking occurred with the release of Ca and Si ions from the composites and the decrease of P ions with slow exchange rate.

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Microneedle-Assisted Percutaneous Transport of Magnesium Sulfate

Current Drug Delivery ◽

10.2174/1567201817666191217093936 ◽

2020 ◽

Vol 17 (2) ◽

pp. 140-147

Author(s):

Karna B. Ghimirey ◽

Kevin Ita

Keyword(s):

Confocal Microscopy ◽

Stratum Corneum ◽

Magnesium Sulfate ◽

Inductively Coupled Plasma ◽

Optical Emission ◽

Magnesium Concentration ◽

Porcine Skin ◽

Time Curve ◽

Student’S T

Objective: In vitro diffusion experiments were performed to assess the permeation of magnesium sulfate across pig skin. Method: The mean thickness of the dermatomed porcine skin was 648 ± 12 µm. Magnesium concentration was measured using inductively coupled plasma-optical emission spectroscopy. Transdermal flux of magnesium sulfate across MN-treated and untreated porcine skin was obtained from the slope of the steady-state linear portion of cumulative amount versus time curve. Results: Statistical analysis of the results was done with Student’s t-test. The transdermal flux of magnesium sulfate across microneedle-treated porcine skin was 134.19 ± 2.4 µg/cm2/h and transdermal flux across untreated porcine skin was 4.64 ± 0.05 µg/cm2/h. Confocal microscopy was used to visualize the microchannels created by a solid microneedle roller (500 µm). Conclusion: From our confocal microscopy studies, it was evident that the 500 μm long microneedles disrupted the stratum corneum and created microchannels measuring 191 ± 37 µm. The increase in transdermal flux across the microneedle-treated skin was statistically significant compared to that of controls, i.e., without the application of microneedles. With the application of microneedles, the transdermal flux of magnesium permeated over 12 h was approximately 33-fold higher in comparison to passive diffusion across an intact stratum corneum.

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Chemistry of Tropical Eucheumatoids: Potential for Food and Feed Applications

Biomolecules ◽

10.3390/biom11060804 ◽

2021 ◽

Vol 11 (6) ◽

pp. 804

Author(s):

Andrea Ariano ◽

Nadia Musco ◽

Lorella Severino ◽

Anna De Maio ◽

Annabella Tramice ◽

...

Keyword(s):

Chemical Analysis ◽

Inductively Coupled Plasma ◽

Mineral Content ◽

Kappaphycus Alvarezii ◽

Optical Emission ◽

Essential Elements ◽

Feed Additive ◽

Inductively Coupled ◽

Food And Feed

The use of seaweeds as additives in animal nutrition may be a valid option to traditional feed as they represent a rich source of minerals, carbohydrates and antioxidants. The aim of this study was to analyze the chemical composition and in vitro antioxidant capacity of two tropical eucheumatoids, Kappaphycus alvarezii and Kappaphycus striatus, in Malaysian wild offshore waters. The chemical analysis was performed via inductively coupled plasma–optical emission spectroscopy for evaluating the concentration of toxic (Cd, Pb, Hg, As) and essential elements (Mn, Fe, Cu, Ni, Zn, Se); NMR spectroscopy was used for carrageenans investigation. Furthermore, the soluble and fat-soluble antioxidant capacities were determined by FRAP, DPPH and ABTS assays. The chemical analysis revealed a higher content of trace elements in K. alvarezii as compared to K. striatus, and both exhibited a high mineral content. No significant differences in metal concentrations were found between the two species. Both samples showed a mixture of prevailing κ- and t-carrageenans. Finally, the levels of soluble and fat-soluble antioxidants in K. alvarezii were significantly higher than in K. striatus. Our findings suggest that K. alvarezii could be used as a potential feed additive because of its favorable chemical and nutritional features.

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Study of Bio-Mineralization of BCP with Compensation of Calcium and Phosphate Ions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.610-613.1391 ◽

2009 ◽

Vol 610-613 ◽

pp. 1391-1394

Author(s):

Hua De Zheng ◽

Ying Jun Wang ◽

Qiang Ma ◽

Cheng Yun Ning ◽

Xiao Feng Chen

Keyword(s):

Free Energy ◽

Calcium Phosphate ◽

Calcium Ions ◽

Biphasic Calcium Phosphate ◽

Porous Ceramic ◽

Apatite Layer ◽

Apatite Formation ◽

Phosphate Ions

In the present study, an Intelligent Multi-parameter Simulated Evaluation in vitro （IMSE system） was used to study the deposition properties of apatite formation on the surface of biphasic calcium phosphate porous ceramic (BCP) from static and dynamic r-SBF. Results showed that apatite formed on the surface of BCP from static and dynamic r-SBF differed between each other. In static r-SBF, ions were transferred by diffusion, which could not compensate the consuming of calcium ions, and mist apatite layer was formed on the surface of samples. But in the dynamic r-SBF, simulated fluid was adjusted precisely and flowed forcedly, the concentrations of ions were homogeneous; with the compensation of ions, calcium and phosphate were supersaturated, and the free energy of apatite formation was negative, bone-like apatite sheets were formed on the surface of samples.

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Enhanced effect of β-tricalcium phosphate phase on neovascularization of porous calcium phosphate ceramics: In vitro and in vivo evidence

Acta Biomaterialia ◽

10.1016/j.actbio.2014.09.028 ◽

2015 ◽

Vol 11 ◽

pp. 435-448 ◽

Cited By ~ 60

Author(s):

Y. Chen ◽

J. Wang ◽

X.D. Zhu ◽

Z.R. Tang ◽

X. Yang ◽

...

Keyword(s):

Calcium Phosphate ◽

Tricalcium Phosphate ◽

Calcium Phosphate Ceramics ◽

Phosphate Phase

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Changes in Characteristics Arising from Processing and the Effect on In Vitro Stability of Calcium Phosphate Ceramics

Characterization and Performance of Calcium Phosphate Coatings for Implants ◽

10.1520/stp25187s ◽

2009 ◽

pp. 111-111-13 ◽

Cited By ~ 2

Author(s):

S Radin ◽

P Ducheyne

Keyword(s):

Calcium Phosphate ◽

Calcium Phosphate Ceramics ◽

In Vitro Stability

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Phosphoserine Functionalized Cements Preserve Metastable Phases, and Reprecipitate Octacalcium Phosphate, Hydroxyapatite, Dicalcium Phosphate, and Amorphous Calcium Phosphate, during Degradation, In Vitro

Journal of Functional Biomaterials ◽

10.3390/jfb10040054 ◽

2019 ◽

Vol 10 (4) ◽

pp. 54 ◽

Cited By ~ 2

Author(s):

Joseph Lazraq Bystrom ◽

Michael Pujari-Palmer

Keyword(s):

Calcium Phosphate ◽

Amorphous Calcium Phosphate ◽

Octacalcium Phosphate ◽

Ionic Concentration ◽

Strong Adhesion ◽

Acidic Conditions ◽

Rapid Transformation ◽

Comparable Mass

Phosphoserine modified cements (PMC) exhibit unique properties, including strong adhesion to tissues and biomaterials. While TTCP-PMCs remodel into bone in vivo, little is known regarding the bioactivity and physiochemical changes that occur during resorption. In the present study, changes in the mechanical strength and composition were evaluated for 28 days, for three formulations of αTCP based PMCs. PMCs were significantly stronger than unmodified cement (38–49 MPa vs. 10 MPa). Inclusion of wollastonite in PMCs appeared to accelerate the conversion to hydroxyapatite, coincident with slight decrease in strength. In non-wollastonite PMCs the initial compressive strength did not change after 28 days in PBS (p > 0.99). Dissolution/degradation of PMC was evaluated in acidic (pH 2.7, pH 4.0), and supersaturated fluids (simulated body fluid (SBF)). PMCs exhibited comparable mass loss (<15%) after 14 days, regardless of pH and ionic concentration. Electron microscopy, infrared spectroscopy, and X-ray analysis revealed that significant amounts of brushite, octacalcium phosphate, and hydroxyapatite reprecipitated, following dissolution in acidic conditions (pH 2.7), while amorphous calcium phosphate formed in SBF. In conclusion, PMC surfaces remodel into metastable precursors to hydroxyapatite, in both acidic and neutral environments. By tuning the composition of PMCs, durable strength in fluids, and rapid transformation can be obtained.

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Crystallization of CaCO3 in Aqueous Solutions with Extremely High Concentrations of NaCl

Crystals ◽

10.3390/cryst9120647 ◽

2019 ◽

Vol 9 (12) ◽

pp. 647

Author(s):

Mengqi Qian ◽

Yuwei Zuo ◽

Zhihao Chen ◽

Xiaoshuang Yin ◽

Ying Liu ◽

...

Keyword(s):

Inductively Coupled Plasma ◽

Optical Emission ◽

Emission Spectrometry ◽

High Concentration ◽

Retention Efficiency ◽

Static Test ◽

Inductively Coupled ◽

High Concentrations ◽

The One ◽

Phosphate Inhibitors

The effect of NaCl at extremely high concentrations from 3.5 to 14 wt. % on the crystallization of CaCO3 was investigated in depth. The static test experiment verified that the Ca2+ retention efficiency (η) of NaCl on CaCO3 scale increased from 31.06% (3.5 wt. %) to 41.56% (14 wt. %). Based on the calculation of supersaturation rations, the high concentration of NaCl could reduce the activity coefficients of [Ca2+] and [CO32−], thus reducing the actual concentration of CaCO3. The CaCO3 deposition rate constants (k) showed that NaCl slowed down the rate of CaCO3 crystallization. The X–ray diffraction (XRD) testing disclosed that the growth of (1 0 4) and (1 1 0) faces from calcite was impeded, while the formation of (1 1 1) face from aragonite was induced by the increasing concentration of NaCl. The inductively coupled plasma optical emission spectrometry (ICP–OES) results indicated that Na+ could be doped into CaCO3, leading to the one–dimensional crystal growth. It was further proved that NaCl heightens the efficiency of the typical phosphate inhibitors (2–phosphonobutane–1,2,4–tricarboxylic acid (PBTCA) and 1–hydroxyethane–1,1–diphosphonic acid (HEDP)) on prohibiting the scale of CaCO3.

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Copper Supplementation in Watering Solution Reaches the Xylem But Does Not Protect Tobacco Plants Against Xylella fastidiosa Infection

Plant Disease ◽

10.1094/pdis-08-19-1748-re ◽

2020 ◽

Vol 104 (3) ◽

pp. 724-730 ◽

Cited By ~ 2

Author(s):

Qing Ge ◽

Paul A. Cobine ◽

Leonardo De La Fuente

Keyword(s):

Biofilm Formation ◽

Inductively Coupled Plasma ◽

Tap Water ◽

Xylella Fastidiosa ◽

In Vitro Study ◽

Optical Emission ◽

In Planta ◽

Inductively Coupled ◽

High Concentrations

Xylella fastidiosa is a xylem-limited plant pathogenic bacterium that causes disease in many crops worldwide. Copper (Cu) is an antimicrobial agent widely used on X. fastidiosa hosts to control other diseases. Although the effects of Cu for control of foliar pathogens are well known, it is less studied on xylem-colonizing pathogens. Previous results from our group showed that low concentrations of CuSO4 increased biofilm formation, whereas high concentrations inhibited biofilm formation and growth in vitro. In this study, we conducted in planta experiments to determine the influence of Cu in X. fastidiosa infection using tobacco as a model. X. fastidiosa-infected and noninfected plants were watered with tap water or with water supplemented with 4 mM or 8 mM of CuSO4. Symptom progression was assessed, and sap and leaf ionome analysis was performed by inductively coupled plasma with optical emission spectroscopy. Cu uptake was confirmed by increased concentrations of Cu in the sap of plants treated with CuSO4-amended water. Leaf scorch symptoms in Cu-supplemented plants showed a trend toward more severe at later time points. Quantification of total and viable X. fastidiosa in planta indicated that CuSO4-amended treatments did not inhibit but slightly increased the growth of X. fastidiosa. Cu in sap was in the range of concentrations that promote X. fastidiosa biofilm formation according to our previous in vitro study. Based on these results, we proposed that the plant Cu homeostasis machinery controls the level of Cu in the xylem, preventing it from becoming elevated to a level that would lead to bacterial inhibition.

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