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Journal ArticleDOI

Investigation into the role of NaOH and calcium ions in the synthesis of calcium phosphate nanoshells

01 Mar 2012-Brazilian Journal of Chemical Engineering (Brazilian Society of Chemical Engineering)-Vol. 29, Iss: 1, pp 147-158

AbstractCalcium phosphate (CaP) nanoshells were prepared using negatively charged liposomes (1,2-dioleoyl-sn-glycero-3-phosphate sodium salt (DOPA)) as a template by base titration synthesis at various concentrations of NaOH and calcium ions. The elemental composition, morphology, particle size, particle size distribution and zeta potential of the products were determined via various characterisation techniques, such as energy-dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), dynamic light scattering (DLS), laser Doppler velocimetry (LDV) and Fourier transform infrared spectroscopy (FTIR). The best results showed that stable spherical CaP nanoshells with a mean particle size of 197.5 ± 5.8 nm and a zeta potential of -34.5 ± 0.6 mV were successfully formed when 0.100 M sodium hydroxide (NaOH) and 0.100 M calcium ions were used. Moreover, an optimal pH of 10.52 and a final Ca/P molar ratio of 0.97 were achieved under these conditions.

Topics: Zeta potential (54%), Calcium (53%), Particle size (52%), Base (chemistry) (52%), Dynamic light scattering (52%)

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Citations
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Book ChapterDOI
TL;DR: This chapter describes current state-of-the-art and recent developments on the subject of nanodimensional CaPO4, starting from synthesis and characterization to biomedical and clinical applications.
Abstract: Nano-scaled particles and crystals play very important roles in biological systems. For example, calcium orthophosphates (CaPO4) with nano-size dimensions represent the basic inorganic building blocks of bones and teeth of mammals. According to recent discoveries in biomineralization, zillions of nanodimensional crystals of biological apatites are nucleated in body fluids, and afterward, they are self-assembled into these complex structures. In addition, both a greater viability and a better proliferation of various types of cells have been detected on smaller crystals of CaPO4. All these effects are due to the higher surface-to-volume ratio, increased reactivity, and biomimetic morphologies of the nano-scaled particles. Thus, the nano-sized and nanocrystalline forms of CaPO4 have a great potential to revolutionize the hard tissue engineering field, starting from bone repair and augmentation to controlled drug delivery systems. Therefore, preparation and application of nanodimensional CaPO4 are the important topics in modern material science, and such formulations have been already tested clinically for various purposes. Currently, more efforts are focused on the possibility of combining nano-scaled CaPO4 with cells, drugs, and other biologically active substances for multipurpose applications. This chapter describes current state-of-the-art and recent developments on the subject, starting from synthesis and characterization to biomedical and clinical applications.

51 citations


BookDOI
01 Jan 2018
TL;DR: In this chapter, a further understanding of the chemical, physical, and biological properties of CPC, along with the clinical applications, is addressed to provide a deeper insight into the regulation mechanism between the material properties and the clinical uses.
Abstract: Calcium phosphate cement (CPC) has opened up a new era in the construction of bone-related defects in biomedical fields. Such unique properties as the easy shaping, injectability in practical use, excellent biocompatibility, and biodegradability of CPC make it a perfect substitution material and maintain the research focus during the years. In this chapter, the brief history, classification, setting mechanism, and kinetics of CPC are introduced. A further understanding of the chemical, physical, and biological properties of CPC, along with the clinical applications, is also addressed to provide a deeper insight into the regulation mechanism between the material properties and the clinical uses.

26 citations


Journal ArticleDOI
TL;DR: Results suggested that functionally graded bilayered membranes hold potential for GBR applications in regenerative dentistry.
Abstract: Barrier membranes are used in periodontal tissue engineering for successful neo-bone tissue formation and prevention of bacterial colonization. We aimed to prepare and characterize novel 7% boron-modified bioactive glass (7B-BG) containing bilayered membrane for this end. We hypothesized that presence of 7B-BG could promote structural and biological properties of guided bone regeneration (GBR) membrane. Cellulose acetate (CA) layer was prepared by solvent casting, and functionally graded layer of CA/gelatin/BG nanoparticles was prepared by electrospinning. 0B-BG, and 7B-BG were synthesized by quick alkali-mediated sol-gel method and were characterized by scanning electron microscopy (SEM) and Fourier-transform Raman spectroscopy. Membranes were cross-linked with glutaraldehyde to preserve their stability. SEM analysis showed the asymmetric nature of membranes consisting of a smooth membrane layer and a rough surface composed of 0B-BG and 7B-BG containing nanofibres. 7B-BG addition increased surface wettability (from 110.5° ± 0.8 to 73.46° ± 7.6) and biodegradability of the membranes. Additionally, a significant increase in Ca-P layer formation was observed in 7B-BG containing group after 1-week incubation in stimulated body fluid. 7B-BG incorporation resulted in a decrease in tensile strength and Young's modulus values. Human dental pulp stem cells showed better attachment, spreading, and proliferation on 7B-BG containing bilayered membranes. Osteogenic differentiation analysis revealed higher alkaline phosphatase (ALP) enzyme activity of cells (~1.5-fold), higher intracellular calcium deposition (approximately twofold), and higher calcium deposition revealed by Alizarin red staining on 7B-BG containing bilayered membranes. Overall, results suggested that functionally graded bilayered membranes hold potential for GBR applications in regenerative dentistry.

10 citations


Journal ArticleDOI
Abstract: Numerous studies have explored the behaviors of ZnO–TiO2 nanoparticles resulting through various routes of fabrication. To date, the utilization of thermal treatment method to convey ZnO–TiO2 nanoparticles has never been considered. In the present study, binary (ZnO)x(TiO2)1−x NPs were effectively blended by using thermal treatment technique. Zinc nitrate and titanium(IV) propoxide with polyvinylpyrrolidone, PVP, were utilized to set up the samples. Energy-dispersive X-ray (EDX) spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction (XRD) spectroscopy, ultraviolet–visible (UV–Vis) spectrophotometer transmission electron microscopy (TEM) and photoluminescence spectroscopy were utilized to examine the impact of changing the molar proportion to the structure and optical features of (ZnO)x(TiO2)1−x NPs. The XRD spectra revealed that after calcination, the amorphous sample had transformed into crystalline nanoparticles. The prepared (ZnO)x(TiO2)1−x NPs average diameter was around 25.922–28.531 nm according to TEM analysis. The analyzation of UV–Vis spectroscopy determined the optical measurements parameters including the energy gap and Urbach energy of binary (ZnO)x(TiO2)1−x NPs. The optical energy gap varied in the range of 3.2496–3.2863 eV as the molar ratio increases from x = 0.24 to x = 0.72. The enhancement within the nanoparticles optical properties suggests a good potential for photocatalysis application.

5 citations


Journal ArticleDOI
TL;DR: Investigation of the effects of TA on the proliferation, mineralization, and morphology of human fetal osteoblast cells found it enhances cell proliferation and causes cell morphology changes, as well as improved mineralization.
Abstract: Tannic acid (TA) is a phenolic compound that might act directly on osteoblast metabolism. The study was performed to investigate the effects of TA on the proliferation, mineralization, and morphology of human fetal osteoblast cells (hFOB 1.19). The cells were divided into TA-treated, untreated, and pamidronate-treated (control drug) groups. Half maximal effective concentration (EC50 ) values for TA and pamidronate were measured using MTT assay. The EC50 of hFOB 1.19 cells treated with TA was 2.94 M. This concentration was more effective compared to the pamidronate (15.27 M). Cell proliferation assay was performed to compare cell viability from Day 1 until Day 14. The morphology of hFOB 1.19 was observed via inverted microscope and scanning electron microscope. Calcium (Ca) and phosphate (P) were assessed using energy-dispersive X-ray (EDX) analysis. Furthermore, the mineralization of hFOB 1.19 was determined by von Kossa staining (P depositions) and Alizarin Red S staining (Ca depositions). The number of cells treated with TA was significantly higher than the two control groups at Day 10 and Day 14. The morphology of cells treated with TA was uniformly fusiform-shaped with filopodia extensions. Besides, globular-like structures of deposited minerals were observed in the TA-treated group. In line with other findings, EDX spectrum analysis confirmed the presence of Ca and P. The cells treated with TA had significantly higher percentage of both minerals at Day 3 and Day 10 compared to the two control groups. In conclusion, TA enhances cell proliferation and causes cell morphology changes, as well as improved mineralization.

4 citations


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Book
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"Investigation into the role of NaOH..." refers background in this paper

  • ...In addition, the greater intensity of the peak at approximately 840 cm (Zhang and Darvell, 2010), with the exception of sample C-DOPA-8 (highest concentration of calcium ions), is attributed to another phosphate group (HPO4), which indicates calcium deficiency (Elliott, 1994)....

    [...]

  • ...In addition, the greater intensity of the peak at approximately 840 cm-1 (Zhang and Darvell, 2010), with the exception of sample C-DOPA-8 (highest concentration of calcium ions), is attributed to another phosphate group (HPO42-), which indicates calcium deficiency (Elliott, 1994)....

    [...]


Book
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1,456 citations


"Investigation into the role of NaOH..." refers background in this paper

  • ...Based on the results of LeGeros (1991), HA contains CO32and is well known to show better bioactivity than stoichiometric HA because of its parallel to the composition of biological apatite in natural bone....

    [...]


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1,085 citations


Journal ArticleDOI
TL;DR: These controls of the size and shape of inorganic nanomaterials are discussed and it is shown that nanoparticles can be considered to be efficient nanoreactors.
Abstract: In the past decade, colloidal solutions have been assumed to be very efficient templates for controlling particle size and shape A large number of groups have used reverse micelles to control the size of spherical nanoparticles This makes it possible to determine the various parameters involved in such processes, and demonstrates that nanoparticles can be considered to be efficient nanoreactors However, some discrepancies arise There are few reports concerning the control of particle shape, and it is still rather difficult to determine the key parameters, such as the adsorption of salts and other molecules, and the synthesis procedure Here, we discuss these controls of the size and shape of inorganic nanomaterials

990 citations


"Investigation into the role of NaOH..." refers background in this paper

  • ...Therefore, the template is not the only controlling factor of the shape of the CaP nanoshells because some discrepancies arise in the synthesis when using templates (Pileni, 2003)....

    [...]


Journal ArticleDOI
01 Jan 1989
TL;DR: Disruption of Surface Potential on Salt Concentration and Surface Charge Density, and Dependence of the Potential on Distance from the Membrane Surface.
Abstract: CONTENTS PERSPECTIVES AND OVERVlEW . . . . . . . . . . . . ...... . . . . . . . . . . . . . . ...... . . . . . . . . . . . . . . . . . .. . . . . . . . . . ....... . . . . . . . . . . . . ... 113 AN ELEMENTARY DISCUSSION OF ELECTROSTATICS AND DOUBLE-LAYER THEORy 115 EXPERIMENTAL TESTS OF THE GOUY-CHAPMAN THEORy 1 19 Dependence of Surface Potential on Salt Concentration and Surface Charge Density 1 19 Dependence of the Potential on Distancefrom the Membrane Surface.... . . . . . . . . ...... . . . . 122 EXPERIMENTALLY OBSERVED LIMITATIONS OF THE THEORy 123 Discreteness-aI-Charge Eff ects ..... . . . . . . . . . . . . ...... ......... . . .. .. . . . . . . . . . . . . . . ...... . . . . . . . . . . ........ . . . . . '123 Finite Size of Ions. . . . .... . . . . . . . . . . . . . ..... . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . ........ . . . 125 Fixed Charges Displacedfrom the Surface . . . . . . . . . . . . . . ........ 126 Forces Between Char.qed Bilayer Membranes . . . . . . . . ...... . . . . . . . . . . ........ . . . . . 126 ALTERNATIVE THEORIES .. . . . . . . . . . . . . . . . . . . .... . . . . . . . . .... . . ...... . . . . . . . . . . . . . . . . . . . . . ... . . . ...... . . . . . . . .. . . . . ... .. . . 127 Donnan Theory.. . . ....... . . . . . . . . . . . . . . . . .... . . . . . . . . . . . . . . . . . . . . . ........ . . . . . . . . . . . .. . . ..... . . . . 127 Manning Condensation Theory and Geometrical Considerations . . . 127 Modern Statistical Mechanical Theories..... .. . . . . . . . . . . . ..... . . . . . . . . . . . . . . . . ....... . . . . . . . . . . 128 BIOLOGICAL IMPLICATIONS 129 Previous Work.. . . ... . . . . . . . . . ....... . . . . . . . . . . . . . . . . ....... . . . . . . . . . . . .... . . . . . . . . . . . . ....... . . . . . . . . . . . . . .... . . . . . . . . . 129 Future Directions: Surface Potentials and Second Messengers.. .. . .. . . ...... . . . . . . . . . .... . . . . . . 129

951 citations


"Investigation into the role of NaOH..." refers background in this paper

  • ...However, the zeta potentials are dependent upon particle size (McLaughlin, 1989)....

    [...]