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1.
Sci Rep ; 14(1): 14562, 2024 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914625

RESUMO

Sugarcane bagasse fly ash, a residual product resulting from the incineration of biomass to generate power and steam, is rich in SiO2. Sodium silicate is a fundamental material for synthesizing highly porous silica-based adsorbents to serve circular practices. Aflatoxin B1 (AFB1), a significant contaminant in animal feeds, necessitates the integration of adsorbents, crucial for reducing aflatoxin concentrations during the digestive process of animals. This research aimed to synthesize aluminosilicate and zinc silicate derived from sodium silicate based on sugarcane bagasse fly ash, each characterized by a varied molar ratio of aluminum (Al) to silicon (Si) and zinc (Zn) to silicon (Si), respectively. The primary focus of this study was to evaluate their respective capacities for adsorbing AFB1. It was revealed that aluminosilicate exhibited notably superior AFB1 adsorption capabilities compared to zinc silicate and silica. Furthermore, the adsorption efficacy increased with higher molar ratios of Al:Si for aluminosilicate and Zn:Si for zinc silicate. The N2 confirmed AFB1 adsorption within the pores of the adsorbent. In particular, the aluminosilicate variant with a molar ratio of 0.08 (Al:Si) showcased the most substantial AFB1 adsorption capacity, registering at 88.25% after an in vitro intestinal phase. The adsorption ability is directly correlated with the presence of surface acidic sites and negatively charged surfaces. Notably, the kinetics of the adsorption process were best elucidated through the application of the pseudo-second-order model, effectively describing the behavior of both aluminosilicate and zinc silicate in adsorbing AFB1.


Assuntos
Aflatoxina B1 , Silicatos de Alumínio , Celulose , Cinza de Carvão , Saccharum , Silicatos , Compostos de Zinco , Silicatos/química , Adsorção , Silicatos de Alumínio/química , Saccharum/química , Aflatoxina B1/química , Cinza de Carvão/química , Celulose/química , Compostos de Zinco/química
2.
Clin Oral Investig ; 28(7): 365, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38849637

RESUMO

OBJECTIVES: Currently, premixed putty-type bioceramic cements (PPBCs) have become popular materials for root-end fillings. This study investigated three root-end filling techniques using PPBCs and calcium silicate-based sealers including EDTA pretreatment. MATERIALS AND METHODS: Ninety root segments were prepared and standardized with an artificial fin and lateral canal, and assigned to three groups (n = 30). Root-end fillings were placed using BC-RRM Putty alone (Group PA), injection of BC sealer followed by BC-RRM Putty (Lid Technique: Group LT) or BC-RRM Putty with BC sealer coating (Deep putty packing technique: Group DP). Half of each group was pretreated with 17% EDTA. The radiographic images of the specimens were assessed by five graders and push-out bond strength tests were conducted. The data were analyzed with a general linear model including two-way ANOVA and chi-square test at a significance level of 5%. RESULTS: DP approach demonstrated significantly higher bond strength than LT (P < 0.05). However, there was no statistically significant difference in bond strength between PA and either DP or LT. EDTA pretreatment had no significant effect on push-out bond strength. Radiographically, for the main canal, PA and DP scored significantly higher than LT. In the fin, PA scored significantly higher than others (P < 0.05). CONCLUSION: Our study highlights variations in root-end filling techniques. Injecting a bulk of bioceramic sealer before the placement of PPBCs may reduce bond strength and radiopacity. The application of PPBCs alone or in the deep putty technique demonstrates potential for favorable outcomes. EDTA pretreatment did not enhance bond-strength. CLINICAL RELEVANCE: Careful selection and application of bioceramic materials and techniques in root-end fillings may influence the outcome of endodontic root-end surgery. When PPBCs and calcium silicate-based sealers are used together for root-end fillings, sealer followed by deep putty application may offer improved bond strength and radiographic fill compared to the lid technique.


Assuntos
Compostos de Cálcio , Teste de Materiais , Materiais Restauradores do Canal Radicular , Silicatos , Materiais Restauradores do Canal Radicular/química , Silicatos/química , Compostos de Cálcio/química , Técnicas In Vitro , Humanos , Colagem Dentária/métodos , Cerâmica/química , Cimentos Dentários/química , Obturação Retrógrada/métodos , Ácido Edético/química , Análise do Estresse Dentário
3.
Environ Geochem Health ; 46(7): 216, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38941030

RESUMO

Iron phosphate-based coating and iron silicate-based coating were used to inhibit the oxidation of sulfide minerals in rainy and submerged environments. The inhibiting effectiveness of coating agents on the oxidation of iron sulfide minerals was investigated using pyrite and rock samples resulting from acid drainage. The film formed with both surface-coating agents was identified by pyrite surface analysis. It was also confirmed that the formation of coatings varies depending on the crystallographic orientation. The inhibitory effects under rainy and submerged conditions were investigated using column experiments. Submerged conditions accelerated deterioration compared to that under rainy conditions. Iron phosphate coating had a significantly better oxidation-inhibitory effect (84.86-98.70%) than iron silicate coating (56.80-92.36%), and at a concentration of 300 mM, H+ elution was inhibited by more than 90% throughout the experiment. Furthermore, methods for effective film formation were investigated in terms of producing Fe3+; (1) application of coating agents mixed with oxidant (H2O2), (2) application of coating agent after the use of the oxidant. In a rainy environment, applying iron phosphate-based coating using the sequential method showed oxidation inhibition effects for cycles 1-9, whereas applying the mixed material showed effects for cycles 9-13. The use of a surface-coating agent after applying an oxidant did not inhibit oxidation. The surface coating agent and the oxidizing agent should be applied as a mixture to form a film.


Assuntos
Ferro , Oxirredução , Fosfatos , Silicatos , Silicatos/química , Ferro/química , Fosfatos/química , Chuva Ácida , Sulfetos/química , Peróxido de Hidrogênio/química , Compostos Férricos/química
4.
Int J Biol Macromol ; 270(Pt 2): 132403, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38754660

RESUMO

This study presents the synthesis of Hec-g@PS through the innovative surface modification of hectorite via photocatalytic atom transfer radical polymerization (ATRP). Then, PLA/Hec-g@PS nanocomposites films was prepared with Hec-g@PS as additives by blown molding technique. Furthermore, the thermal degradation kinetics and crystallization kinetics during the thermal degradation of PLA based nanocomposites films were investigated with simultaneous rheology and FTIR technology. The findings indicated that the activation energies for PLA and PLA/Hec-g@PS were -54,702.12 J/mol and -107,963.47 J/mol, respectively, demonstrating that Hec-g@PS substantially influenced PLA thermal stability. Additionally, while the crystallization rates of PLA based films decreased with rising degradation temperatures. Quantum chemical calculations revealed that the mode of interaction between Hec-g@PS and PLA was mainly dominated by dispersion, supplemented by electrostatic and induced interactions of -22.2103 kcal/mol, -16.0779 kcal/mol and -5.4954 kcal/mol, respectively. The combination of crystallization kinetics and quantum chemical calculations further confirmed that Hec-g@PS promoted the alignment of PLA molecular chains due to the enhanced interaction force between them. Hec-g@PS functioned as a nucleating agent, facilitating PLA crystallization and effectively mitigated its thermal degradation. Hec-g@PS as a nucleating agent provides valuable insights into the potential application prospects of biodegradable materials, particularly in the fields of biomedicine and packaging.


Assuntos
Cristalização , Nanocompostos , Poliésteres , Reologia , Poliésteres/química , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , Temperatura , Silicatos/química
5.
Sci Rep ; 14(1): 10798, 2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734777

RESUMO

The nucleation of carbonate-containing apatite on the biomaterials surface is regarded as a significant stage in bone healing process. In this regard, composites contained hydroxyapatite (Ca10(PO4)6(OH)2, HA), wollastonite (CaSiO3, WS) and polyethersulfone (PES) were synthesized via a simple solvent casting technique. The in-vitro bioactivity of the prepared composite films with different weight ratios of HA and WS was studied by placing the samples in the simulated body fluid (SBF) for 21 days. The results indicated that the the surface of composites containing 2 wt% HA and 4 wt% WS was completely covered by a thick bone-like apatite layer, which was characterized by Grazing incidence X-ray diffraction, attenuated total reflectance-Fourier transform infrared spectrometer, field emission electron microscopy and energy dispersive X-ray analyzer (EDX). The degradation study of the samples showed that the concentration of inorganic particles could not influence the degradability of the polymeric matrix, where all samples expressed similar dexamethasone (DEX) release behavior. Moreover, the in-vitro cytotoxicity results indicated the significant cyto-compatibility of all specimens. Therefore, these findings revealed that the prepared composite films composed of PES, HA, WS and DEX could be regarded as promising bioactive candidates with low degradation rate for bone tissue engineering applications.


Assuntos
Materiais Biocompatíveis , Substitutos Ósseos , Durapatita , Nanocompostos , Silicatos , Durapatita/química , Nanocompostos/química , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Silicatos/química , Materiais Biocompatíveis/química , Compostos de Cálcio/química , Liberação Controlada de Fármacos , Dexametasona/química , Dexametasona/farmacologia , Polímeros/química , Humanos , Difração de Raios X , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier , Animais
6.
PeerJ ; 12: e17237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699192

RESUMO

Background: Root perforation repair presents a significant challenge in dentistry due to inherent limitations of existing materials. This study explored the potential of a novel polydopamine-based composite as a root repair material by evaluating its sealing efficacy, radiopacity, and surface topography. Methods: Confocal microscopy assessed sealing ability, comparing the polydopamine-based composite to the gold standard, mineral trioxide aggregate (MTA). Radiopacity was evaluated using the aluminium step wedge technique conforming to ISO standards. Surface roughness analysis utilized atomic force microscopy (AFM), while field emission scanning electron microscopy (FESEM) visualized morphology. Results: The polydopamine-based composite exhibited significantly superior sealing efficacy compared to MTA (P < 0.001). Radiopacity reached 3 mm aluminium equivalent, exceeding minimum clinical requirements. AFM analysis revealed a smooth surface topography, and FESEM confirmed successful composite synthesis. Conclusion: This study demonstrates promising properties of the polydopamine-based composite for root perforation repair, including superior sealing efficacy, clinically relevant radiopacity, and smooth surface topography. Further investigation is warranted to assess its clinical viability and potential translation to endodontic practice.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Indóis , Óxidos , Polímeros , Materiais Restauradores do Canal Radicular , Silicatos , Propriedades de Superfície , Polímeros/química , Indóis/química , Silicatos/química , Compostos de Cálcio/química , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Compostos de Alumínio/química , Humanos , Combinação de Medicamentos , Microscopia Eletrônica de Varredura , Microscopia de Força Atômica/métodos , Microscopia Confocal , Teste de Materiais , Raiz Dentária/lesões , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/cirurgia
7.
Biosens Bioelectron ; 258: 116343, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38718636

RESUMO

Recently, the non-covalently activated supramolecular scaffold method has become a prominent research area in the field of intelligent materials. Here, the inorganic clay (LP) promoted the AIE properties of 4,4',4″,4‴-(ethene-1,1,2,2-tetrayltetrakis(benzene-4,1-diyl))tetrakis(1-ethylpyridin-1-ium) (P-TPE), showing an astonishing 42-fold enhancement of the emission intensity of the yellow-green luminescence and a 34-fold increase of the quantum yield via organic-inorganic supramolecular strategy as well as the efficient light-harvesting properties (energy transfer efficiency up to 33 %) after doping with the dye receptor Rhodamine B. Furthermore, the full-color spectral regulation, including white light, was achieved by adjusting the ratio of the donor to the acceptor component and co-assembling with the carbon dots (CD). Interestingly, this TPE-based non-covalently activated full-color supramolecular light-harvesting system (LHS) could be achieved not only in aqueous media but also in the hydrogel and the solid state. More importantly, this panchromatic tunable supramolecular LHS exhibited the multi-mode and quadruple digital logic encryption property as well as the specific detection ability towards the perfluorobutyric acid and the perfluorobutanesulfonic acid, which are harmful to human health in drinking water. This result develops a simple, convenient and effective approach for the intelligent anti-counterfeiting and the pollutant sensing.


Assuntos
Técnicas Biossensoriais , Poluentes Químicos da Água , Técnicas Biossensoriais/métodos , Poluentes Químicos da Água/análise , Corantes Fluorescentes/química , Fluorocarbonos/química , Luminescência , Silicatos/química , Rodaminas/química , Limite de Detecção , Pontos Quânticos/química
8.
Environ Sci Pollut Res Int ; 31(25): 37298-37315, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38769263

RESUMO

Five phyllosilicates (kaolinite, montmorillonite, saponite, sepiolite and palygorskite) have been selected as starting materials for the synthesis of zeolites. Among them, kaolinite and montmorillonite display the lowest Si/Al molar ratio leading to aluminosilicates with high crystallinity. Thus, the hydrothermal treatment under basic conditions forms 4A zeolite when kaolinite is used as starting material while 13X zeolite is obtained when montmorillonite is used as starting material. The microporosity and CO2-adsorption capacity of the prepared zeolites are directly related to its crystallinity. Thus, in order to improve it, raw phyllosilicates were subjected to a microwave-assisted treatment to remove undesired Mg or Fe-species, which have a negative effect in the assembling of the zeolites by hydrothermal basic conditions in a second step. The highest adsorption value was 3.85 mmol/g at 25 °C and 760 mm of Hg for Mont-A-B sample after the consecutive treatments.


Assuntos
Dióxido de Carbono , Zeolitas , Zeolitas/química , Adsorção , Dióxido de Carbono/química , Silicatos/química , Bentonita/química
9.
Environ Sci Pollut Res Int ; 31(27): 39194-39207, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38814553

RESUMO

The effects of calcium-to-silicon ratio on the properties of fly ash (FA)-based tobermorite and its removal performance of Zn2+ and Mn2+ were studied. The calcium-to-silicon ratio had a significant effect on the structural properties of the tobermorite samples. The specific surface area, pore volume, and average pore size of mesoporous tobermorite samples with different calcium-to-silicon ratios (0.8TOB, 1.2TOB, and 1.6TOB) were much larger than those of FA, and those of 1.2TOB were the largest, which were 53.29 m2/g, 0.448 cm3/g, and 30.50 nm, respectively. The removal efficiencies of Zn2+ and Mn2+ by 1.2TOB were 84.19% and 47.67%, respectively, which were much higher than those of 0.8TOB (60.62% and 42.41%), 1.6TOB (46.69% and 24.31%), and FA (4.13% and 6.95%). The adsorption of Zn2+ and Mn2+ by 0.8TOB, 1.2TOB, and 1.6TOB was corresponding to the pseudo-second-order kinetic model and Langmuir isotherm model. Particularly, 1.2 TOB showed the highest maximum adsorption capacities of Zn2+ and Mn2+ calculated from the Langmuir model, which were 129.70 mg/g and 82.09 mg/g, respectively. Moreover, the adsorption mechanisms might be due to the combination with -OH and the interlayer adsorption of the samples. This research provides new insight into the fly ash-based adsorbents towards Zn2+ and Mn2+ in wastewater.


Assuntos
Cálcio , Cinza de Carvão , Manganês , Zinco , Cinza de Carvão/química , Zinco/química , Manganês/química , Cálcio/química , Adsorção , Silício/química , Silicatos/química , Compostos de Cálcio
10.
Biomacromolecules ; 25(6): 3335-3344, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38717974

RESUMO

Hemostatic powder is widely employed for emergency bleeding control due to its ability to conform to irregularly shaped wounds, ease of use, and stable storage. However, current powders exhibit limited tissue adhesion and insufficient support for thrombus formation, making them easily washed away by blood. In this study, a hybrid powder (QAL) was produced by mixing quaternized chitosan (QCS) powder, catechol-modified alginate (Cat-SA) powder, and laponite (Lap) powder. Upon addition of QAL, the blood quickly transformed to a robust and adhesive blood gel. The adhesion strength of the blood gel was up to 31.33 ± 1.56 kPa. When compared with Celox, QAL showed superior performance in promoting hemostasis. Additionally, QAL exhibited effectiveness in eliminating bacteria while also demonstrating outstanding biocompatibility with cells and blood. These favorable properties, including strong coagulation, adhesion to wet tissue, antibacterial activity, biosafety, ease of use, and stable storage, make QAL a promising emergency hemostatic agent.


Assuntos
Alginatos , Coagulação Sanguínea , Quitosana , Hemostáticos , Pós , Silicatos , Hemostáticos/química , Hemostáticos/farmacologia , Silicatos/química , Animais , Coagulação Sanguínea/efeitos dos fármacos , Pós/química , Quitosana/química , Alginatos/química , Alginatos/farmacologia , Humanos , Camundongos , Géis/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Hemostasia/efeitos dos fármacos
11.
Braz Oral Res ; 38: e028, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597547

RESUMO

Acidic pH can modify the properties of repair cements. In this study, volumetric change and solubility of the ready-to-use bioceramic repair cement Bio-C Repair (BCR, Angelus, Londrina, PR, Brazil) were evaluated after immersion in phosphate-buffered saline (PBS) (pH 7.0) or butyric acid (pH 4.5). Solubility was determined by the difference in initial and final mass using polyethylene tubes measuring 4 mm high and 6.70 mm in internal diameter that were filled with BCR and immersed in 7.5 mL of PBS or butyric acid for 7 days. The volumetric change was established by using bovine dentin tubes measuring 4 mm long with an internal diameter of 1.5 mm. The dentin tubes were filled with BCR at 37°C for 24 hours. Scanning was performed with micro-computed tomography (micro-CT; SkyScan 1176, Bruker, Kontich, Belgium) with a voxel size of 8.74 µm. Then, the specimens were immersed in 1.5 mL of PBS or butyric acid at and 37 °C for 7 days. After this period, a new micro-CT scan was performed. Bio-C Repair showed greater mass loss after immersion in butyric acid when compared with immersion in PBS (p<0.05). Bio-C Repair showed volumetric loss after immersion in butyric acid and increase in volume after immersion in PBS (p<0.05). The acidic pH influenced the solubility and dimensional stability of the Bio-C Repair bioceramic cement, promoting a higher percentage of solubility and decrease in volumetric values.


Assuntos
Óxidos , Materiais Restauradores do Canal Radicular , Animais , Bovinos , Solubilidade , Óxidos/química , Compostos de Cálcio/química , Microtomografia por Raio-X , Ácido Butírico , Teste de Materiais , Cimentos Dentários/química , Cimentos de Ionômeros de Vidro , Concentração de Íons de Hidrogênio , Silicatos/química , Materiais Restauradores do Canal Radicular/química
12.
J Hazard Mater ; 470: 134190, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593659

RESUMO

Organophosphorus compounds (OPs), such as VX, pose a significant threat due to their neurotoxic and hazardous properties. Skin decontamination is essential to avoid irreversible effects. Fuller's earth (FE), a phyllosilicate conventionally employed in powder form, has demonstrated decontamination capacity against OPs. The aim of this study was to develop a formulation that forms a film on the skin, with a significant OP removal capacity (>95 %) coupled with sequestration capabilities, favorable drying time and mechanical properties to allow for easy application and removal, particularly in emergency context. Various formulations were prepared using different concentrations of polyvinyl alcohol (PVA), FE and surfactants. Their removal and sequestration capacity was tested using paraoxon-ethyl (POX), a chemical that simulates the behavior of VX. Formulations with removal capacity levels surpassing 95 % were mechanically characterized and cell viability assays were performed on Normal Human Dermal Fibroblast (NHDF). The four most promising formulations were used to assess decontamination efficacy on pig ear skin explants. These formulations showed decontamination levels ranging from 84.4 ± 4.7 % to 96.5 ± 1.3 %, which is equivalent to current decontamination methods. These results suggest that this technology could be a novel and effective tool for skin decontamination following exposure to OPs.


Assuntos
Descontaminação , Paraoxon , Pele , Descontaminação/métodos , Animais , Pele/efeitos dos fármacos , Humanos , Suínos , Paraoxon/toxicidade , Paraoxon/química , Compostos de Alumínio/química , Sobrevivência Celular/efeitos dos fármacos , Silicatos/química , Álcool de Polivinil/química , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Tensoativos/química , Fibroblastos/efeitos dos fármacos
13.
Carbohydr Polym ; 336: 122128, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670759

RESUMO

Traditional submucosal filling materials frequently show insufficient lifting height and duration during clinical procedures. Here, the anionic polysaccharide polymer sodium carboxymethyl starch and cationic Laponite to prepare a hydrogel with excellent shear-thinning ability through physical cross-linking, so that it can achieve continuous improvement of the mucosal cushion through endoscopic injection. The results showed that the hydrogel (56.54 kPa) had a lower injection pressure compared to MucoUp (68.56 kPa). The height of submucosal lifting height produced by hydrogel was higher than MucoUp, and the height maintenance ability after 2 h was 3.20 times that of MucoUp. At the same time, the hydrogel also showed satisfactory degradability and biosafety, completely degrading within 200 h. The hemolysis rate is as low as 0.76 %, and the cell survival rate > 80 %. Subcutaneous implantation experiments confirmed that the hydrogel showed no obvious systemic toxicity. Animal experiments clearly demonstrated the in vivo feasibility of using hydrogels for submucosal uplift. Furthermore, successful endoscopic submucosal dissection was executed on a live pig stomach, affirming the capacity of hydrogel to safely and effectively facilitate submucosal dissection and mitigate adverse events, such as bleeding. These results indicate that shear-thinning hydrogels have a wide range applications as submucosal injection materials.


Assuntos
Hidrogéis , Amido , Amido/análogos & derivados , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Amido/química , Suínos , Camundongos , Mucosa Gástrica/metabolismo , Ressecção Endoscópica de Mucosa/métodos , Injeções , Humanos , Hemólise/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Silicatos/química
14.
Int J Biol Macromol ; 267(Pt 1): 131580, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38688788

RESUMO

Despite the clinical success of tricalcium silicate (TCS)-based materials in endodontics, the inferior handling characteristic, poor anti-washout property and slow setting kinetics hindered their wider applications. To solve these problems, an injectable fast-setting TCS/ß-tricalcium phosphate/monocalcium phosphate anhydrous (ß-TCP/MCPA) cement was developed for the first time by incorporation of hydroxypropyl methylcellulose (HPMC) and ß-TCP/MCPA. The physical-chemical characterization (setting time, anti-washout property, injectability, compressive strength, apatite mineralization and sealing property) of TCS/(ß-TCP/MCPA) were conducted. Its hydration mechanism was also investigated. Furthermore, the cytocompatibility and osteogenic/odontogenic differentiation of stem cells isolated from human exfoliated deciduous teeth (SHED) treated with TCS/ß-TCP/MCPA were studied. The results showed that HPMC could provide TCS with good anti-washout ability and injectability but slow hydration process. However, ß-TCP/MCPA effectively enhanced anti-washout characteristics and reduced setting time due to faster hydration kinetics. TCS/(ß-TCP/MCPA) obtained around 90 % of injection rate and high compressive strength whereas excessive additions of ß-TCP/MCPA compromised its injectability and compressive strength. TCS/(ß-TCP/MCPA) can induce apatite deposition and form a tight marginal sealing at the dentin-cement interface. Additionally, TCS/(ß-TCP/MCPA) showed good biocompatibility and promoted osteo/odontogenic differentiation of SHED. In general, our results indicated that TCS/(ß-TCP/MCPA) may be particularly promising as an injectable bioactive cements for endodontic treatment.


Assuntos
Compostos de Cálcio , Fosfatos de Cálcio , Derivados da Hipromelose , Silicatos , Silicatos/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Compostos de Cálcio/química , Humanos , Derivados da Hipromelose/química , Osteogênese/efeitos dos fármacos , Teste de Materiais , Diferenciação Celular/efeitos dos fármacos , Força Compressiva , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cimentos Dentários/química , Cimentos Dentários/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia
15.
J Mech Behav Biomed Mater ; 155: 106563, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38678747

RESUMO

OBJECTIVES: The aim of the study was to investigate the impact of organic additives (binder, plasticizer, and the cross-linking ink) in the formulation of water-based feedstocks on the properties of a dental feldspathic glass-ceramic material developed for the slurry-based additive manufacturing technology "LSD-print." MATERIAL AND METHODS: Three water-based feldspathic feedstocks were produced to study the effects of polyvinyl alcohol (AC1) and poly (sodium 4-styrenesulfonate) (AC2) as binder systems. A feedstock without organic additives was tested as the control group (CG). Disc-shaped (n = 15) and bar (n = 7) specimens were slip-cast and characterized in the green and fired states. In the green state, density and flexural strength were measured. In the fired state, density, shrinkage, flexural strength (FS), Weibull modulus, fracture toughness (KIC), Martens parameters, and microstructure were analyzed. Disc-shaped and bar specimens were also cut from commercially available CAD/CAM blocks and used as a target reference (TR) for the fired state. RESULTS: In the green state, CG showed the highest bulk density but the lowest FS, while the highest FS in the green state was achieved with the addition of a cross-linking ink. After firing, no significant differences in density and a similar microstructure were observed for all slip-cast groups, indicating that almost complete densification could be achieved. The CAD/CAM specimens showed the highest mean FS, Weibull modulus, and KIC, with significant differences between some of the slip-cast groups. SIGNIFICANCE: These results suggest that the investigated feedstocks are promising candidates for the slurry-based additive manufacturing of restorations meeting the class 1a requirements according to DIN EN ISO 6871:2019-01.


Assuntos
Cerâmica , Teste de Materiais , Silicatos , Cerâmica/química , Silicatos/química , Fenômenos Mecânicos , Resistência à Flexão , Fenômenos Físicos , Materiais Dentários/química
16.
Dent Mater J ; 43(3): 420-429, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38644213

RESUMO

This study investigated the wettability and consistency of various endodontic sealers, both inorganic and organic, and evaluated their sealing ability of root canals using the single-cone obturation technique, with and without ethylenediaminetetraacetic acid (EDTA) treatment. Bovine root canals were endodontically prepared and filled in preparation for the dye penetration test with toluidine blue solution. All sealers exhibited contact angles similar to or lower than dentin and displayed superior consistency. Among the sealers, organic sealers used without EDTA treatment showed reduced dye penetration compared to inorganic sealers. However, some inorganic and organic sealers showed dye penetration in the sealer and dentin of root canals subjected to EDTA treatment. In conclusion, the single-cone obturation technique, combined with these endodontic sealers, achieved close contact with root canal dentin due to their wettability and consistency. However, the sealing ability of certain sealers was influenced by EDTA treatment.


Assuntos
Ácido Edético , Teste de Materiais , Materiais Restauradores do Canal Radicular , Obturação do Canal Radicular , Molhabilidade , Materiais Restauradores do Canal Radicular/química , Animais , Bovinos , Obturação do Canal Radicular/métodos , Combinação de Medicamentos , Infiltração Dentária , Cavidade Pulpar , Silicatos/química , Propriedades de Superfície , Compostos de Cálcio/química , Resinas Epóxi/química , Colagem Dentária/métodos , Compostos de Alumínio/química , Técnicas In Vitro , Óxidos/química , Hidróxido de Cálcio/química , Preparo de Canal Radicular/métodos , Guta-Percha/química , Dentina/efeitos dos fármacos , Corantes
17.
Bioresour Technol ; 400: 130694, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614149

RESUMO

Recycling waste into commercial products is a profitable strategy but the lifetime of immobilized cells for long-term waste treatment remains a problem. This study presents alternative cell immobilization methods for valorizing food waste (FW) and oily food waste (OFW) to microbial carotenoids and proteins. Carriers (pumice or smectite), magnetite nanoparticles, and isolated photosynthetic bacteria were integrated to obtain magnetically recoverable bacteria-pumice and bacteria-smectite nanocomposites. After recycling five batches (50 d), chemical oxygen demand removal from FW reached 76% and 78% with the bacteria-pumice and bacteria-smectite nanocomposite treatments, respectively, and oil degradation in OFW reached 71% and 62%, respectively. Destructive changes did not occur, suggesting the durability of nanocomposites. The used nanocomposites had no impact on the lifespan of Moina macrocopa or water quality as assessed by toxicity analysis. Bacteria-pumice and bacteria-smectite nanocomposites are efficient for food waste recycling and do not require secondary treatment before being discharged into the environment.


Assuntos
Bactérias , Células Imobilizadas , Nanocompostos , Silicatos , Zooplâncton , Nanocompostos/química , Silicatos/química , Silicatos/farmacologia , Animais , Células Imobilizadas/metabolismo , Alimentos , Reciclagem , Análise da Demanda Biológica de Oxigênio , Resíduos , Biodegradação Ambiental , Óleos/química , Perda e Desperdício de Alimentos
18.
Waste Manag ; 182: 225-236, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38677140

RESUMO

This article explores the impact of thermally treated asbestos-cement waste (ACWT) on metakaolin-based geopolymers, using liquid sodium silicate (LSS) and liquid potassium silicate (LKS) as alkali activators. Through statistical mixture design, various formulations were tested for rheological parameters, mineralogical composition, efflorescence mass, electrical conductivity, compressive strength, and CO2 emissions. Formulations with sodium silicate exhibited higher yield stress compared to those with potassium silicate, while flash setting occurred in LKS-activated mixtures with high ACWT content. Alkali activator content significantly affected mechanical strength and leachate electrical conductivity. CO2 emissions were higher for LKS-activated formulations but lower for those with more ACWT. Finally, by incorporating ACWT, it was possible to optimize the formulations, resulting in high compressive strength, reduced free ions, and reduced negative environmental impact.


Assuntos
Amianto , Dióxido de Carbono , Materiais de Construção , Silicatos , Dióxido de Carbono/análise , Silicatos/química , Materiais de Construção/análise , Amianto/análise , Força Compressiva , Resíduos Industriais/análise , Condutividade Elétrica , Temperatura Alta
19.
Nanotechnology ; 35(31)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38663370

RESUMO

The overuse of antibiotics currently results in the presence of various antibiotics being detected in water bodies, which poses potential risks to human health and the environment. Therefore, it is highly significant to remove antibiotics from water. In this study, we developed novel rod-like NiCo-phyllosilicate hybrid catalysts on calcined natural zeolite (NiCo@C-zeolite) via a facile one-pot process. The presence of the zeolite served as both a silicon source and a support, maintaining a high specific surface area of the NiCo@C-zeolite. Remarkably, NiCo@C-zeolite exhibited outstanding catalytic performance in antibiotic degradation under PMS activation. Within just 5 min, the degradation rate of metronidazole (MNZ) reached 96.14%, ultimately achieving a final degradation rate of 99.28%. Furthermore, we investigated the influence of catalyst dosage, PMS dosage, MNZ concentration, initial pH value, and various inorganic anions on the degradation efficiency of MNZ. The results demonstrated that NiCo@C-zeolite displayed outstanding efficacy in degrading MNZ under diverse conditions and maintained a degradation rate of 94.86% at 60 min after three consecutive cycles of degradation. Free radical quenching experiments revealed that SO•-4played a significant role in the presence of NiCo@C-zeolite-PMS system. These findings indicate that the novel rod-like NiCo-phyllosilicate hybrid catalysts had excellent performance in antibiotic degradation.


Assuntos
Antibacterianos , Zeolitas , Zeolitas/química , Antibacterianos/química , Antibacterianos/síntese química , Catálise , Poluentes Químicos da Água/química , Metronidazol/química , Purificação da Água/métodos , Silicatos/química
20.
Environ Sci Pollut Res Int ; 31(22): 32168-32182, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38649599

RESUMO

Although calcined clay-blended cement offers higher performance and durability compared to neat Portland cement (PC), its extensive use of natural clay leads to the depletion of natural non-renewable resources. To address this concern, this study focuses on the utilization of supplementary cementitious materials-based waste products as a substitute for PC. The blended cement was optimized with a low replacement level of 10 wt.% calcined Fanja clay (FNJ) as a low-grade metakaolin (MK) and 90 wt.% PC. Various types of industrial solid wastes (ISWs) were incorporated into the PC-FNJ blend in place of PC. The ISWs utilized included silicate-rich wastes, such as silica fume (SF) and glass waste (GW) powder, as well as silicate-less waste, such as marble dust (MD). The results revealed that incorporating 10 wt.% SF into the PC-FNJ mixture resulted in a considerable decrease in the flow rate while improving its early mechanical strength. GW, as another silicate waste, also enhanced early mechanical properties but not as much as SF. However, the composite of PC-FNJ-GW exhibited higher workability than the neat PC, PC-FNJ, and PC-FNJ-SF. The mixtures of PC-FNJ-MD demonstrated the same trend. Embedding SF into PC-FNJ-GW and PC-FNJ-MD substantially decreased both their flowability and mechanical properties. Nonetheless, all composites containing ISWs showed higher flexural strength, higher resistivity to chloride diffusivity, and higher or comparable acid and salt resistivity.


Assuntos
Materiais de Construção , Resíduos Industriais , Silicatos , Resíduos Sólidos , Resíduos Sólidos/análise , Resíduos Industriais/análise , Silicatos/química , Materiais de Construção/análise , Materiais de Construção/normas , Força Compressiva , Resistência à Flexão , Ultrassom , Fenômenos Mecânicos , Ácidos Sulfúricos/química , Sais/química , Permeabilidade
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