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1.
Heliyon ; 9(5): e16355, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37305474

RESUMO

[This corrects the article DOI: 10.1016/j.heliyon.2021.e06598.].

2.
Heliyon ; 7(11): e08344, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34816040

RESUMO

This paper focused on the analysis of the crystal structure and phase transformation of CaCO3 synthesized by simple solution method from 0.5 M Ca(NO3)2 precursor and 0.5 M Na2CO3 precipitant at ambient temperature (300 K). The pH of the sample solution at various reaction times of 5, 10, 15, and 30 min were measured and correlated with the supersaturating condition in the presence of the Na2CO3 which is responsible for vaterite phase formation. The formation of the polymorph structure of obtained CaCO3 powders was characterized using powder X-ray diffraction patterns and their crystal structure and phase transformation were evaluated using the Rietveld refinement method. Moreover, the qualitative analysis of the CaCO3 powders phase was conducted by Fourier Transform Infrared (FTIR) spectroscopy to evaluate the effect of reaction time correlated with their crystal formation. The XRD analysis showed that the vaterite formation was 89 % at a reaction time of 15 min and confirmed also by FTIR that the amount of vaterite increased due to the effect of increasing reaction time. The crystallite size of vaterite was stable at 36 nm at the reaction time of 15 and 30 min. The morphology of the CaCO3 powders obtained from Scanning Electron Microscope (SEM) was spherical with sizes of 2-5 µm. It was highlighted that the supersaturating condition started occurred at a reaction time of 15 min at pH 7.88 which was responsible for vaterite formation took place. It was concluded that the amount of precipitant (Na2CO3) and reaction times play an important role to determine the saturation of carbonate source to allow vaterite phase formation of CaCO3 powders to occur.

3.
Materials (Basel) ; 14(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34442948

RESUMO

Appropriately engineered CaCO3 vaterite has interesting properties such as biodegradability, large surface area, and unique physical and chemical properties that allow a variety of uses in medical applications, mainly in dental material as the scaffold. In this paper, we report the synthesis of vaterite from Ca(NO3)2·4H2O without porogen to obtain a highly pure and porous microsphere for raw material of calcium phosphate as the scaffold in our future development. CaCO3 properties were investigated at two different temperatures (20 and 27 °C) and stirring speeds (800 and 1000 rpm) and at various reaction times (5, 10, 15, 30, and 60 min). The as-prepared porous CaCO3 powders were characterized by FTIR, XRD, SEM, TEM, and BET methods. The results showed that vaterite with purity 95.3%, crystallite size 23.91 nm, and porous microsphere with lowest pore diameter 3.5578 nm was obtained at reaction time 30 min, temperature reaction 20 °C, and stirring speed 800 rpm. It was emphasized that a more spherical microsphere with a smaller size and nanostructure contained multiple primary nanoparticles received at a lower stirring speed (800 rpm) at the reaction time of 30 min. One of the outstanding results of this study is the formation of the porous vaterite microsphere with a pore size of ~3.55 nm without any additional porogen or template by using a simple mixing method.

4.
Heliyon ; 7(4): e06598, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33937538

RESUMO

This study was conducted to investigate the odontogenic proliferation and differentiation of dental pulp stem cells (DPSCs) after induction by nanoparticle mineral trioxide (NMT). DPSCs were isolated from permanent teeth and placed in tubes containing Dulbecco's modified Eagle's medium, followed by immunocytochemistry analysis. The viability of DPSCs exposed to NMT was measured using MTT assay with trypan blue dye exclusion. Alkaline phosphatase (ALP) activity was evaluated using ALP colorimetric reactions by reacting NMT supernatants with fluorescent-specific ALP substrates. The concentration of osteocalcin was determined using an instant human osteocalcin enzyme-linked immunosorbent assay (ELISA) kit. A human dentin sialophosphoprotein (DSPP) ELISA kit coated with anti-human DSPP antibody was employed to measure DSPP levels. There was a significant difference between ALP activity after exposing the cells to NMT and trioxide mineral aggregate on days 3, 7, and 21. Osteocalcin activity showed a significant difference on days 3, 7, 14, and 21. There was a significant difference in DSPP levels on days 7 and 21. DPSCs exposed to NMT and to trioxide mineral aggregate showed extracellular matrix formation on day 7 and 14, respectively. Furthermore, NMT may effectively increase the proliferation and differentiation of DPSCs as well as their maturation toward odontoblasts.

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