Ewerton Vieira | Universidade Estadual do Piauí (original) (raw)

Papers by Ewerton Vieira

Arquivos Brasileiros de Cardiologia, 2021

Minerals, 2021

Osteoporosis is a public health problem, with bone loss being the main consequence. Hydroxyapatit... more Osteoporosis is a public health problem, with bone loss being the main consequence. Hydroxyapatite (HA) has been largely used as a bioceramic to stimulate bone growth. In our work, a cerium-containing HA (Ce-HA) has been proposed and its effects on the antimicrobial and bone-inducing properties were investigated. The synthesis of the materials occurred by the suspension–precipitation method (SPM). The XRD (X-ray Diffraction) confirmed the crystalline phase, and the Rietveld refinement confirmed the crystallization of HA and Ce-HA in a hexagonal crystal structure in agreement with ICSD n° 26205. Characterizations by FT-IR (Fourier Transform Infrared Spectroscopy), XPS (X-ray Photoemission Spectroscopy), and FESEM-EDS (Field Emission Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy) confirmed the presence of cerium (Ce3+ and Ce4+). The antibacterial activity of Has was evaluated against Staphylococcus aureus 25,923 and Escherichia coli 25,922 strains, which revealed t...

Polímeros, 2021

To produce polysaccharide-based hydrogels and cerium (Ce3+) doped hydroxyapatite plus chitosan an... more To produce polysaccharide-based hydrogels and cerium (Ce3+) doped hydroxyapatite plus chitosan and collagen to enable future applications in the treatment of joint degeneration. Hydrogel production and characterization were performed with Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis (TGA) and cytotoxicity testing with MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. A final biomaterial composition was Kelcogel® Gelana (58%), chitosan (22.3%), Ce3+ doped hydroxyapatite (10.7%) and bovine collagen (9%), or selected aspect material gelatinous physical color with whitish color and can be injected. The biomaterial composition was proven in the FTIR and TGA, which also provided the maximum supported temperature. In the MTT assay, despite the reduction in viability of the experimental group compared to the control group, cell viability remained approximately 90%. In the FTIR and TGA tests, the material composition was proven. The material does not present cytotoxic behavior for the MTT test, being an alternative for the treatment of joint diseases.

Ceramics International, 2020

Abstract Bacterial cellulose (BC) membranes biosynthesized by Komagataeibacter rhaeticus AF1 stra... more Abstract Bacterial cellulose (BC) membranes biosynthesized by Komagataeibacter rhaeticus AF1 strain were used as a platform for precipitating cerium-doped calcium phosphates (Ce:CaP), which were synthetized by successive soaking of BC membranes in solutions containing Ca2+, PO43− and Ce3+ precursor ions. After obtaining the as-prepared composites, BC-Ce:CaP was submitted to a thermal treatment at 600 °C for 3 h, and Ce:CaP was characterized by scanning electronic microscopy (SEM), energy dispersive X-ray spectrometry (EDX), thermogravimetric analysis (TG), derivative thermogravimetric analysis (DTG) and X-ray diffraction (XRD). Ce:CaP presented hydroxyapatite, chlorapatite and buchwaldite (sodium calcium phosphate) phases and revealed a trabecular structure composed per nanowires with interconnected pores. Furthermore, BC-Ce:CaP and Ce:CaP show cell viability and has been suggested for use as a mineral scaffold.

International Journal of Nanomedicine, 2020

Background: The facile preparation of oxygen-generating microparticles (M) consisting of Polycapr... more Background: The facile preparation of oxygen-generating microparticles (M) consisting of Polycaprolactone (PCL), Pluronic F-127, and calcium peroxide (CPO) (PCL-F-CPO-M) fabricated through an electrospraying process is disclosed. The biological study confirmed the positive impact from the oxygen-generating microparticles on the cell growth with high viability. The presented technology could work as a prominent tool for various tissue engineering and biomedical applications. Methods: The oxygen-generated microparticles fabricated through electrospraying processes were thoroughly characterization through various methods such as X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) analysis, and scanning electron microscopy (SEM)/SEM-Energy Dispersive Spectroscopy (EDS) analysis. Results: The analyses confirmed the presence of the various components and the porous structure of the microparticles. Spherical shape with spongy characteristic microparticles were obtained with negative charge surface (ζ =-16.9) and a size of 17.00 ± 0.34 μm. Furthermore, the biological study performed on rat chondrocytes demonstrated good cell viability and the positive impact of increasing the amount of CPO in the PCL-F-CPO-M. Conclusion: This technological platform could work as an important tool for tissue engineering due to the ability of the microparticles to release oxygen in a sustained manner for up to 7 days with high cell viability.

Journal of Functional Biomaterials, 2020

Microparticles (MPs) with controlled morphologies and sizes have been investigated by several res... more Microparticles (MPs) with controlled morphologies and sizes have been investigated by several researchers due to their importance in pharmaceutical, ceramic, cosmetic, and food industries to just name a few. In particular, the electrospray (ES) technique has been shown to be a viable alternative for the development of single particles with different dimensions, multiple layers, and varied morphologies. In order to adjust these properties, it is necessary to optimize different experimental parameters, such as polymer solvent, voltage, flow rate (FR), type of collectors, and distance between the collector and needle tip, which will all be highlighted in this review. Moreover, the influence and contributions of each of these parameters on the design and fabrication of polymeric MPs are described. In addition, the most common configurations of ES systems for this purpose are discussed, for instance, the main configuration of an ES system with monoaxial, coaxial, triaxial, and multi-capi...

Materials, 2019

Hydroxyapatite (HAp) is a ceramic material composing the inorganic portion of bones. Ionic substi... more Hydroxyapatite (HAp) is a ceramic material composing the inorganic portion of bones. Ionic substitutions enhance characteristics of HAp, for example, calcium ions (Ca2+) by cerium ions (Ce3+). The use of HAp is potentialized through biopolymers, cashew gum (CG), and gellan gum (GG), since CG/GG is structuring agents in the modeling of structured biocomposites, scaffolds. Ce-HApCG biocomposite was synthesized using a chemical precipitation method. The obtained material was frozen (–20 °C for 24 h), and then vacuum dried for 24 h. The Ce-HApCG was characterized by X-Ray diffractograms (XRD), X-ray photoemission spectra (XPS), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy (EDS). XRD and FTIR showed that Ce-HApCG was successfully synthesized. XRD showed characteristic peaks at 2θ = 25.87 and 32.05, corresponding to the crystalline planes (0 0 2) and (2 1 1), respectively, while phosphate bands were...

International Journal of Advances in Medical Biotechnology - IJAMB, 2018

Bacterial cellulose (BC) is a nanofibrous biomaterial biosynthetized by a series of acetic bacter... more Bacterial cellulose (BC) is a nanofibrous biomaterial biosynthetized by a series of acetic bacteria with unique properties with application in many tissue engineering purposes. Calcium phosphates (CPs), mainly hydroxyapatite, are bioceramics that possess similar composition of host bones and are able to stimulate osteoconduction and osteointegration to living tissues. Bacterial cellulose-calcium phosphates composites have caught the attention of researchers by their excellent mechanical properties and biocompatibility, being considered an excellent proposal to development of new synthetic grafts to bone tissue engineering. The minireview presented here focuses on various fabrication methods used to prepare and novel applications of BC-CPs composites and their applications in BTE.Keywords:

Minerals, 2021

The development of photocatalystsor their modification to obtain new photocatalytic performances ... more The development of photocatalystsor their modification to obtain new photocatalytic performances for the removal of contaminants is a challenge. Hydroxyapatite (HAp), (Ca10(PO4)6(OH)2), is an inorganic component with a high superficial area and low toxicity and the presence of metal in its structure can be an interesting strategy for the photocatalytic approach. This work aimed to synthesize gallium-containing HAp (Ga-HAp) as a promising material for photocatalytic performance. The synthesis was performed by the suspension–precipitation method. The material was characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Morphological analysis employed field emission scanning electron microscope (FESEM) and the elemental analysis by energy-dispersive spectroscopy (EDS). To evaluate the photocatalytic activity, methylene blue (MB) dye was used as a pollutant model under UV light for 120 min. The influence of Ga-HAp concentration (0.25, 0.50, and 1.00 g·L−1) an...

Biomaterials - Physics and Chemistry - New Edition, May 2, 2018

Hydroxyapatite stands out between biomaterials due to its properties of osteoconduction and osteo... more Hydroxyapatite stands out between biomaterials due to its properties of osteoconduction and osteoinduction, being adequate to be used in bone grafts. The high stability and flexibility of the structure allows for several biomedical applications, for example, the use as polysaccharide based on the scaffold formulations and the cationic substitutions occurring through the doping of the material using metals, which may enhance biological characteristics, such as improving the action of combating bacterial infections in situ. This study was a research of articles and patents, without and with time restriction (2007-2017), which contain information about hydroxyapatite in the tissue engineering, biomedical, doped with cerium and its properties of antibacterial activity. There were also searches of products and companies that commercialize these types of materials aimed at tissue engineering area. Scopus was used for searched of articles and were EPO, USPTO, and INPI used for patents, and to search for products and companies were used search engines. Few papers were found to associate all the keywords, but the ones found are recent works, thus showing a new area with potential to be investigated.

Arquivos Brasileiros de Cardiologia, 2021

Minerals, 2021

Osteoporosis is a public health problem, with bone loss being the main consequence. Hydroxyapatit... more Osteoporosis is a public health problem, with bone loss being the main consequence. Hydroxyapatite (HA) has been largely used as a bioceramic to stimulate bone growth. In our work, a cerium-containing HA (Ce-HA) has been proposed and its effects on the antimicrobial and bone-inducing properties were investigated. The synthesis of the materials occurred by the suspension–precipitation method (SPM). The XRD (X-ray Diffraction) confirmed the crystalline phase, and the Rietveld refinement confirmed the crystallization of HA and Ce-HA in a hexagonal crystal structure in agreement with ICSD n° 26205. Characterizations by FT-IR (Fourier Transform Infrared Spectroscopy), XPS (X-ray Photoemission Spectroscopy), and FESEM-EDS (Field Emission Scanning Electron Microscope-Energy Dispersive X-ray Spectroscopy) confirmed the presence of cerium (Ce3+ and Ce4+). The antibacterial activity of Has was evaluated against Staphylococcus aureus 25,923 and Escherichia coli 25,922 strains, which revealed t...

Polímeros, 2021

To produce polysaccharide-based hydrogels and cerium (Ce3+) doped hydroxyapatite plus chitosan an... more To produce polysaccharide-based hydrogels and cerium (Ce3+) doped hydroxyapatite plus chitosan and collagen to enable future applications in the treatment of joint degeneration. Hydrogel production and characterization were performed with Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis (TGA) and cytotoxicity testing with MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. A final biomaterial composition was Kelcogel® Gelana (58%), chitosan (22.3%), Ce3+ doped hydroxyapatite (10.7%) and bovine collagen (9%), or selected aspect material gelatinous physical color with whitish color and can be injected. The biomaterial composition was proven in the FTIR and TGA, which also provided the maximum supported temperature. In the MTT assay, despite the reduction in viability of the experimental group compared to the control group, cell viability remained approximately 90%. In the FTIR and TGA tests, the material composition was proven. The material does not present cytotoxic behavior for the MTT test, being an alternative for the treatment of joint diseases.

Ceramics International, 2020

Abstract Bacterial cellulose (BC) membranes biosynthesized by Komagataeibacter rhaeticus AF1 stra... more Abstract Bacterial cellulose (BC) membranes biosynthesized by Komagataeibacter rhaeticus AF1 strain were used as a platform for precipitating cerium-doped calcium phosphates (Ce:CaP), which were synthetized by successive soaking of BC membranes in solutions containing Ca2+, PO43− and Ce3+ precursor ions. After obtaining the as-prepared composites, BC-Ce:CaP was submitted to a thermal treatment at 600 °C for 3 h, and Ce:CaP was characterized by scanning electronic microscopy (SEM), energy dispersive X-ray spectrometry (EDX), thermogravimetric analysis (TG), derivative thermogravimetric analysis (DTG) and X-ray diffraction (XRD). Ce:CaP presented hydroxyapatite, chlorapatite and buchwaldite (sodium calcium phosphate) phases and revealed a trabecular structure composed per nanowires with interconnected pores. Furthermore, BC-Ce:CaP and Ce:CaP show cell viability and has been suggested for use as a mineral scaffold.

International Journal of Nanomedicine, 2020

Background: The facile preparation of oxygen-generating microparticles (M) consisting of Polycapr... more Background: The facile preparation of oxygen-generating microparticles (M) consisting of Polycaprolactone (PCL), Pluronic F-127, and calcium peroxide (CPO) (PCL-F-CPO-M) fabricated through an electrospraying process is disclosed. The biological study confirmed the positive impact from the oxygen-generating microparticles on the cell growth with high viability. The presented technology could work as a prominent tool for various tissue engineering and biomedical applications. Methods: The oxygen-generated microparticles fabricated through electrospraying processes were thoroughly characterization through various methods such as X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) analysis, and scanning electron microscopy (SEM)/SEM-Energy Dispersive Spectroscopy (EDS) analysis. Results: The analyses confirmed the presence of the various components and the porous structure of the microparticles. Spherical shape with spongy characteristic microparticles were obtained with negative charge surface (ζ =-16.9) and a size of 17.00 ± 0.34 μm. Furthermore, the biological study performed on rat chondrocytes demonstrated good cell viability and the positive impact of increasing the amount of CPO in the PCL-F-CPO-M. Conclusion: This technological platform could work as an important tool for tissue engineering due to the ability of the microparticles to release oxygen in a sustained manner for up to 7 days with high cell viability.

Journal of Functional Biomaterials, 2020

Microparticles (MPs) with controlled morphologies and sizes have been investigated by several res... more Microparticles (MPs) with controlled morphologies and sizes have been investigated by several researchers due to their importance in pharmaceutical, ceramic, cosmetic, and food industries to just name a few. In particular, the electrospray (ES) technique has been shown to be a viable alternative for the development of single particles with different dimensions, multiple layers, and varied morphologies. In order to adjust these properties, it is necessary to optimize different experimental parameters, such as polymer solvent, voltage, flow rate (FR), type of collectors, and distance between the collector and needle tip, which will all be highlighted in this review. Moreover, the influence and contributions of each of these parameters on the design and fabrication of polymeric MPs are described. In addition, the most common configurations of ES systems for this purpose are discussed, for instance, the main configuration of an ES system with monoaxial, coaxial, triaxial, and multi-capi...

Materials, 2019

Hydroxyapatite (HAp) is a ceramic material composing the inorganic portion of bones. Ionic substi... more Hydroxyapatite (HAp) is a ceramic material composing the inorganic portion of bones. Ionic substitutions enhance characteristics of HAp, for example, calcium ions (Ca2+) by cerium ions (Ce3+). The use of HAp is potentialized through biopolymers, cashew gum (CG), and gellan gum (GG), since CG/GG is structuring agents in the modeling of structured biocomposites, scaffolds. Ce-HApCG biocomposite was synthesized using a chemical precipitation method. The obtained material was frozen (–20 °C for 24 h), and then vacuum dried for 24 h. The Ce-HApCG was characterized by X-Ray diffractograms (XRD), X-ray photoemission spectra (XPS), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy (EDS). XRD and FTIR showed that Ce-HApCG was successfully synthesized. XRD showed characteristic peaks at 2θ = 25.87 and 32.05, corresponding to the crystalline planes (0 0 2) and (2 1 1), respectively, while phosphate bands were...

International Journal of Advances in Medical Biotechnology - IJAMB, 2018

Bacterial cellulose (BC) is a nanofibrous biomaterial biosynthetized by a series of acetic bacter... more Bacterial cellulose (BC) is a nanofibrous biomaterial biosynthetized by a series of acetic bacteria with unique properties with application in many tissue engineering purposes. Calcium phosphates (CPs), mainly hydroxyapatite, are bioceramics that possess similar composition of host bones and are able to stimulate osteoconduction and osteointegration to living tissues. Bacterial cellulose-calcium phosphates composites have caught the attention of researchers by their excellent mechanical properties and biocompatibility, being considered an excellent proposal to development of new synthetic grafts to bone tissue engineering. The minireview presented here focuses on various fabrication methods used to prepare and novel applications of BC-CPs composites and their applications in BTE.Keywords:

Minerals, 2021

The development of photocatalystsor their modification to obtain new photocatalytic performances ... more The development of photocatalystsor their modification to obtain new photocatalytic performances for the removal of contaminants is a challenge. Hydroxyapatite (HAp), (Ca10(PO4)6(OH)2), is an inorganic component with a high superficial area and low toxicity and the presence of metal in its structure can be an interesting strategy for the photocatalytic approach. This work aimed to synthesize gallium-containing HAp (Ga-HAp) as a promising material for photocatalytic performance. The synthesis was performed by the suspension–precipitation method. The material was characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Morphological analysis employed field emission scanning electron microscope (FESEM) and the elemental analysis by energy-dispersive spectroscopy (EDS). To evaluate the photocatalytic activity, methylene blue (MB) dye was used as a pollutant model under UV light for 120 min. The influence of Ga-HAp concentration (0.25, 0.50, and 1.00 g·L−1) an...

Biomaterials - Physics and Chemistry - New Edition, May 2, 2018

Hydroxyapatite stands out between biomaterials due to its properties of osteoconduction and osteo... more Hydroxyapatite stands out between biomaterials due to its properties of osteoconduction and osteoinduction, being adequate to be used in bone grafts. The high stability and flexibility of the structure allows for several biomedical applications, for example, the use as polysaccharide based on the scaffold formulations and the cationic substitutions occurring through the doping of the material using metals, which may enhance biological characteristics, such as improving the action of combating bacterial infections in situ. This study was a research of articles and patents, without and with time restriction (2007-2017), which contain information about hydroxyapatite in the tissue engineering, biomedical, doped with cerium and its properties of antibacterial activity. There were also searches of products and companies that commercialize these types of materials aimed at tissue engineering area. Scopus was used for searched of articles and were EPO, USPTO, and INPI used for patents, and to search for products and companies were used search engines. Few papers were found to associate all the keywords, but the ones found are recent works, thus showing a new area with potential to be investigated.