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1.
Phys Med Biol ; 69(19)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39231474

RESUMEN

Objective.The objective of this study is to explore the capabilities of photon-counting computed tomography (PCCT) in simultaneously imaging and differentiating materials with close atomic numbers, specifically barium (Z= 56) and iodine (Z= 53), which is challenging for conventional computed tomography (CT).Approach.Experiments were conducted using a bench-top PCCT system equipped with a cadmium zinc telluride detector. Various phantom setups and contrast agent concentrations (1%-5%) were employed, along with a biological sample. Energy thresholds were tuned to the K-edge absorption energies of barium (37.4 keV) and iodine (33.2 keV) to capture multi-energy CT images. K-edge decomposition was performed using K-edge subtraction and principal component analysis (PCA) techniques to differentiate and quantify the contrast agents.Main results.The PCCT system successfully differentiated and accurately quantified barium and iodine in both phantom combinations and a biological sample, achieving high correlations (R2≈1) between true and reconstructed concentrations. PCA outperformed K-edge subtraction, particularly in the presence of calcium, by providing superior differentiation between barium and iodine.Significance.This study demonstrates the potential of PCCT for reliable, detailed imaging in both clinical and research settings, particularly for contrast agents with similar atomic numbers. The results suggest that PCCT could offer significant improvements in imaging quality over conventional CT, especially in applications requiring precise material differentiation.


Asunto(s)
Bario , Yodo , Fantasmas de Imagen , Fotones , Tomografía Computarizada por Rayos X , Yodo/química , Tomografía Computarizada por Rayos X/métodos , Bario/química , Procesamiento de Imagen Asistido por Computador/métodos , Medios de Contraste/química , Análisis de Componente Principal
2.
Luminescence ; 39(7): e4836, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39023133

RESUMEN

The near-infrared (NIR) down-conversion process for broadband sensitization has been studied in Eu2+-Nd3+ co-doped BaAl2O4. This material has a broad absorption band of 200-480 nm and can convert photons in the visible region into NIR photons. The NIR emission at 1064 nm, attributed to the Nd3+:4F3/2 → 4I11/2 transition, matches the bandgap of Si, allowing Si solar cells to utilize the solar spectrum better. The energy transfer (ET) process between Eu2+ and Nd3+ was demonstrated using photoluminescence spectra and luminescence decay curves, and Eu2+ may transfer energy to Nd3+ through the cooperative energy transfer (CET) to achieve the down-conversion process. The energy transfer efficiency (ETE) and theoretical quantum efficiency (QE) were 68.61% and 156.34%, respectively, when 4 mol% Nd3+ was introduced. The results indicate that BaAl2O4:Eu2+-Nd3+ can serve as a potential modulator of the solar spectrum and is expected to be applied to Si solar cells.


Asunto(s)
Europio , Rayos Infrarrojos , Neodimio , Silicio , Energía Solar , Europio/química , Silicio/química , Neodimio/química , Luminiscencia , Transferencia de Energía , Bario/química , Mediciones Luminiscentes
3.
J Mol Graph Model ; 132: 108834, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39083885

RESUMEN

This study undertook a comprehensive examination of the double perovskite complex Ba2FeWO6, investigating its structural, electrical, magnetic, thermal and elastic characteristics. The study used density functional theory (DFT), specifically the full potential linearized augmented plane wave (FP-LAPW) method. It also used different approximations, including the generalized gradient approximation (GGA) and the modified Trans-Blaha (TB-mBJ) approach, to improve the accuracy of the band gap estimation more accurate. Additionlly, the GGA + U approach, incorporating the Hubbard correction term (U), was utilized. Our findings indicate that Ba2FeWO6 exhibits indirect half-metallic band gaps in the (L-X) direction, with value of 0.91 eV and a net magnetic moment of 4 µB, predominatly influenced by the iron atom. The compound demonstrated exceptional characteristics suitable for thermoelectric applications, particularly at lower temperatures. Furthermore, the elasticity analysis revealed low brittleness, facilitates its manipulation in manufacturing procedures.


Asunto(s)
Compuestos de Calcio , Teoría Funcional de la Densidad , Óxidos , Titanio , Titanio/química , Óxidos/química , Compuestos de Calcio/química , Modelos Moleculares , Bario/química , Temperatura
4.
J Hazard Mater ; 475: 134923, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38889469

RESUMEN

This study investigates the co-precipitation of calcium and barium ions in hypersaline wastewater under the action of Bacillus licheniformis using microbially induced carbonate precipitation (MICP) technology, as well as the bactericidal properties of the biomineralized product vaterite. The changes in carbonic anhydrase activity, pH, carbonate and bicarbonate concentrations in different biomineralization systems were negatively correlated with variations in metal ion concentrations, while the changes in polysaccharides and protein contents in bacterial extracellular polymers were positively correlated with variations in barium concentrations. In the mixed calcium and barium systems, the harvested minerals were vaterite containing barium. The increasing concentrations of calcium promoted the incorporation and adsorption of barium onto vaterite. The presence of barium significantly increased the contents of O-CO, N-CO, and Ba-O in vaterite. Calcium promoted barium precipitation, but barium inhibited calcium precipitation. After being treated by immobilized bacteria, the concentrations of calcium and barium ions decreased from 400 and 274 to 1.72 and 0 mg/L (GB/T15454-2009 and GB8978-1996). Intracellular minerals were also vaterite containing barium. Extracellular vaterite exhibited bactericidal properties. This research presents a promising technique for simultaneously removing and recycling hazardous heavy metals and calcium in hypersaline wastewater.


Asunto(s)
Bario , Calcio , Precipitación Química , Aguas Residuales , Aguas Residuales/química , Bario/química , Calcio/química , Calcio/metabolismo , Bacillus/metabolismo , Carbonato de Calcio/química , Carbonato de Calcio/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/química , Reciclaje , Carbonatos/química , Anhidrasas Carbónicas/metabolismo , Purificación del Agua/métodos
5.
Bioresour Technol ; 406: 130996, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38885729

RESUMEN

Microalgae immobilization in alginate beads shows promise for biomass production and water pollution control. However, carrier instability and mass transfer limitations are challenges. This study introduces buoyant barium alginate bubble beads (BABB), which offer exceptional stability and enhance Chlorella vulgaris growth. In just 12 days, compared to traditional calcium alginate beads, BABB achieved a 20 % biomass increase while minimizing cell leakage and simplifying harvesting. BABB optimization involved co-immobilization with BG-11 medium, enrichment of CO2 in internal bubbles, and the integration of Fe nanoparticles (FeNPs). In the open raceway pond reactor, these optimizations resulted in a 39 % increase in biomass over 7 days compared to the unoptimized setup in closed flasks. Furthermore, enhancements in pigment and organic matter production were observed, along with improved removal of ammonia nitrogen and phosphate. These results highlight the overall advantages of BABB for microalgae immobilization, offering a scientific foundation for their effective utilization.


Asunto(s)
Alginatos , Chlorella vulgaris , Ácido Glucurónico , Chlorella vulgaris/crecimiento & desarrollo , Alginatos/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Biomasa , Células Inmovilizadas/metabolismo , Bario/química , Microalgas/crecimiento & desarrollo , Microesferas , Reactores Biológicos , Dióxido de Carbono
6.
Chemosphere ; 361: 142569, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38852627

RESUMEN

Chemical oxo-precipitation (COP) is an enhanced precipitation method for boron removal with the conversion of boric acid to perborate anions. When using barium-based precipitant, the boron can be effectively precipitated as barium perborates (BaPBs). The phase transformation of BaPBs from amorphous (A-BaPB, Ba(B(OH)3OOH)2) to crystalline (C-BaPB, BaB2(OO)2(OH)4) form is crucial for effective boron removal. However, scaling up this phase transformation of BaPBs is hindered by poor diffusion. This study aims to promote the growth of C-BaPB through seed-induced crystal growth, eliminating the need for phase transformation. By examining the relationship between crystal growth rate and supersaturation, surface spiral growth was identified as the rate-limiting step of the growth of micron-sized seeds near pHpzc. To enable continuous crystal growth, granular seeds of C-BaPB were prepared and employed as the medium for fluidized-bed crystallization (FBC). The system reached steady state 3 hydraulic retention times, achieving 90% boron removal. The effect of surface loading, ionic strength, and dosages on steady-state crystal growth rate was studied, revealing a shift of the rate-limiting step in FBC to diffusion. Lastly, the system that constituted of two FBCs in-series for sequential crystallization of A-BaPB and C-BaPB was demonstrated. The integrated system provided 97.8% of boron removal from synthetic wastewater containing 500 mg-B/L, with 92.3% of boron crystallized on the granular seeds of BaPBs.


Asunto(s)
Bario , Boro , Cristalización , Boro/química , Bario/química , Boratos/química , Precipitación Química , Contaminantes Químicos del Agua/química
7.
J Inorg Biochem ; 256: 112569, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38701687

RESUMEN

The clinical success of [223Ra]RaCl2 (Xofigo®) for the palliative treatment of bone metastases in patients with prostate cancer has highlighted the therapeutic potential of α-particle emission. Expanding the applicability of radium-223 in Targeted Alpha Therapy of non-osseous tumors is followed up with significant interest, as it holds the potential to unveil novel treatment options in the comprehensive management of cancer. Moreover, the use of barium radionuclides, like barium-131 and -135m, is still unfamiliar in nuclear medicine applications, although they can be considered as radium-223 surrogates for imaging purposes. Enabling these applications requires the establishment of chelators able to form stable complexes with radium and barium radionuclides. Until now, only a limited number of ligands have been suggested and these molecules have been primarily inspired by existing structures known for their ability to complex large metal cations. However, a systematic inspection of chelators specifically tailored to Ra2+ and Ba2+ has yet to be conducted. This work delves into a comprehensive investigation of a series of small organic ligands, aiming to unveil the coordination preferences of both radium-223 and barium-131/135m. Electronic binding energies of both metal cations to each ligand were theoretically computed via Density Functional Theory calculations (COSMO-ZORA-PBE-D3/TZ2P), while thermodynamic stability constants were experimentally determined for Ba2+-ligand complexes by potentiometry, NMR and UV-Vis spectroscopies. The outcomes revealed malonate, 2-hydroxypyridine 1-oxide and picolinate as the most favorable building blocks to design multidentate chelators. These findings serve as foundation guidelines, propelling the development of cutting-edge radium-223- and barium-131/135m-based radiopharmaceuticals for Targeted Alpha Therapy and theranostics of cancer.


Asunto(s)
Radio (Elemento) , Radio (Elemento)/química , Radio (Elemento)/uso terapéutico , Humanos , Radioisótopos/química , Complejos de Coordinación/química , Complejos de Coordinación/uso terapéutico , Bario/química , Partículas alfa/uso terapéutico , Quelantes/química , Quelantes/uso terapéutico , Neoplasias/tratamiento farmacológico , Nanomedicina Teranóstica/métodos , Metales Alcalinotérreos/química , Radiofármacos/química , Radiofármacos/uso terapéutico
8.
ACS Appl Bio Mater ; 7(5): 2704-2709, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38635922

RESUMEN

The structural integrity, assembly yield, and biostability of DNA nanostructures are influenced by the metal ions used to construct them. Although high (>10 mM) concentrations of divalent ions are often preferred for assembling DNA nanostructures, the range of ion concentrations and the composition of the assembly products vary for different assembly conditions. Here, we examined the unique ability of Ba2+ to retard double crossover DNA motifs by forming a low mobility species, whose mobility on the gel is determined by the concentration ratio of DNA and Ba2+. The formation of this electrophoretically retarded species is promoted by divalent ions such as Mg2+, Ca2+, and Sr2+ when combined with Ba2+ but not on their own, while monovalent ions such as Na+, K+, and Li+ do not have any effect on this phenomenon. Our results highlight the complex interplay between the metal ions and DNA self-assembly and could inform the design of DNA nanostructures for applications that expose them to multiple ions at high concentrations.


Asunto(s)
Bario , ADN , Ensayo de Materiales , Tamaño de la Partícula , ADN/química , Bario/química , Nanoestructuras/química , Electroforesis , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química
9.
J Mater Chem B ; 12(17): 4232-4247, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38601990

RESUMEN

The design and synthesis of nano- and microcarriers for preclinical and clinical imaging are highly attractive due to their unique features, for example, multimodal properties. However, broad translation of these carriers into clinical practice is postponed due to the unknown biological reactivity of the new components used for their synthesis. Here, we have developed microcarriers (∼2-3 µm) and  nanocarriers (<200 nm) made of barium carbonate (BaCO3) for multiple imaging applications in vivo. In general, barium in the developed carriers can be used for X-ray computed tomography, and the introduction of a diagnostic isotope (99mTc) into the BaCO3 structure enables in vivo visualization using single-photon emission computed tomography. The bioimaging has shown that the radiolabeled BaCO3 nano- and microcarriers had different biodistribution profiles and tumor accumulation efficiencies after intratumoral and intravenous injections. In particular, in the case of intratumoral injection, all the types of used carriers mostly remained in the tumors (>97%). For intravenous injection, BaCO3 microcarriers were mainly localized in the lung tissues. However, BaCO3 NPs were mainly accumulated in the liver. These results were supported by ex vivo fluorescence imaging, direct radiometry, and histological analysis. The BaCO3-based micro- and nanocarriers showed negligible in vivo toxicity towards major organs such as the heart, lungs, liver, kidneys, and spleen. This study provides a simple strategy for the design and fabrication of the BaCO3-based carriers for the development of dual bioimaging.


Asunto(s)
Bario , Carbonatos , Tomografía Computarizada de Emisión de Fotón Único , Animales , Ratones , Carbonatos/química , Bario/química , Tomografía Computarizada por Rayos X , Tamaño de la Partícula , Nanopartículas/química , Humanos , Distribución Tisular
10.
Dalton Trans ; 53(15): 6501-6506, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38511607

RESUMEN

In the crystals of alkaline earth metal compounds strontium and barium with the non-steroidal anti-inflammatory drug nimesulide, the strontium cation is nine-coordinated with a distorted tricapped trigonal prismatic geometry TCTPR-9, whereas the ten-coordinated barium ion exhibits a distorted tetracapped trigonal prismatic geometry TCTPR-10.


Asunto(s)
Metales Alcalinotérreos , Estroncio , Sulfonamidas , Bario/química , Estroncio/química , Metales Alcalinotérreos/química , Antiinflamatorios no Esteroideos
11.
J Mech Behav Biomed Mater ; 149: 106215, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37984284

RESUMEN

The piezoelectric effect is widely known to have a significant physiological function in bone development, remodeling, and fracture repair. As a well-known piezoelectric material, barium titanate is particularly appealing as a scaffold layer to improve bone tissue engineering applications. Currently, the chemical bath deposition method is used to prepare green synthesized barium titanate coatings to improve mechanical and biological characteristics. Molarity of the solutions, an essential parameter in chemical synthesis, is changed at room temperature (0.1-1.2 Molar) to prepare coatings. The XRD spectra for as deposited coatings indicate amorphous behavior, while polycrystalline nature of coatings is observed after annealing (300 °C). Coatings prepared with solutions of relatively low molarities, i.e. from 0.1 to 0.8 M, exhibit mixed tetragonal - cubic phases. However, the tetragonal phase of Perovskite barium titanate is observed using solution molarities of 1.0 M and 1.2 M. Relatively high value of transmission, i.e. ∼80%, is observed for the coatings prepared with high molarities. Band gap of annealed coatings varies between 3.47 and 3.70 eV. For 1.2 M sample, the maximum spontaneous polarization (Ps) is 0.327x10-3 (µC/cm2) and the residual polarization (Pr) is 0.072x10-3 (µC/cm2). For 1.2M solution, a high hardness value (1510 HV) is recorded, with a fracture toughness of 28.80 MPam-1/2. Low values of weight loss, after dipping the coatings in simulated body fluid, is observed. The antibacterial activity of BaTiO3 is tested against E. coli and Bacillus subtilis. Drug encapsulation capability is also tested for different time intervals. As a result, CBD-based coatings are a promising nominee for use as scaffold and protective coatings.


Asunto(s)
Escherichia coli , Óxidos , Bario/química , Titanio/farmacología , Titanio/química
12.
Luminescence ; 38(3): 308-317, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36718528

RESUMEN

A series of tellurite-based glasses are prepared by using a melt-quenching method. The effect of cerium on the physical, thermal, structural, optical, spectroscopic, and shielding properties of barium tellurite glass samples is studied. It has been observed that the thermal stability factor increases with increasing cerium ion (Ce3+ ) concentration. The density and other physical parameters such as ion concentration and molar volume are calculated using the Archimedes principle. An increase in optical band gap and density suggests a decrement in non-bridging oxygens. These results are in accordance with Raman results. The blue emission in prepared glasses is studied in terms of International Commission on Illumination chromaticity coordinates. Moreover, various shielding properties such as mass attenuation coefficient, linear attenuation coefficient, effective atomic number, half-value layer, and tenth-value layer have also been determined to understand the photon shielding characteristics of as-prepared glass samples.


Asunto(s)
Cerio , Bario/química , Análisis Espectral , Telurio/química
13.
Inorg Chem ; 61(6): 2768-2782, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35099955

RESUMEN

Trivalent europium-based monochromatic red light-emitting phosphors are an essential component to realize high-performance smart lighting devices; however, the concentration and thermal quenching restrict their usage. Here, we report a series of efficient Eu3+-substituted Li3Y3BaSr(MoO4)8 red-emitting phosphors based on a stratified scheelite structure with negligible concentration and thermal quenching. All of the host and phosphor compositions crystallize in monoclinic crystal structure (space group C2/c). All of the phosphor compositions produce narrow-band red emission (FWHM ∼6 nm), which is highly apparent to the human eyes, and lead to exceptional chromatic saturation of the red spectral window. Concurrently, detailed investigations were carried out to comprehend the concentration and thermal quenching mechanism. Absolute quantum yields as high as 88.5% were obtained for Li3Y0.3Eu2.7BaSr(MoO4)8 phosphor with virtuous thermal stability (at 400 K, retaining 87% of its emission intensity). The light-emitting diodes were constructed by coupling Li3BaSrY0.3Eu2.7(MoO4)8 red phosphor with a near-UV LED chip (395 nm) operated at 20 mA forward bias, and the hybrid white LED (an organic yellow dye + red Li3Y3BaSr(MoO4)8:Eu3+ phosphor integrated with an NUV LED chip) showed a low CCT (6645 K), high CRI (83) values, and CIE values of x = 0.303; y = 0.368, which indicated that the synthesized phosphors can be a suitable red component for white LEDs. In addition, we have systematically investigated the Sm3+ and Sm3+, Eu3+ activation in Li3Y3BaSr(MoO4)8 to display the latent use of the system in plant growth applications and establish that the phosphor exhibits orange red emission with an intense deep-red emission (645 nm (4G5/2 → 6H9/2)). The phytochrome (Pr) absorption spectrum well matched the fabricated deep-red LED (by integrating a NUV LED + Li3Y3BaSr(MoO4)8:Sm3+ and Eu3+ phosphor) spectral lines.


Asunto(s)
Color , Luz , Sustancias Luminiscentes/farmacología , Plantas/efectos de los fármacos , Bario/química , Bario/farmacología , Europio/química , Europio/farmacología , Humanos , Litio/química , Litio/farmacología , Sustancias Luminiscentes/química , Mediciones Luminiscentes , Molibdeno/química , Molibdeno/farmacología , Fósforo/química , Fósforo/farmacología , Samario/química , Samario/farmacología , Estroncio/química , Estroncio/farmacología , Temperatura
14.
Anal Biochem ; 642: 114481, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34843699

RESUMEN

By conducting binding experiments at a range of temperatures T using isothermal titration calorimetry (ITC), one can obtain two estimates of the binding enthalpy - calorimetric (ΔH°cal) from the experiments at each T, and van't Hoff (ΔH°vH) from the T dependence of the binding constant K°. From thermodynamics it is clear that these two must be identical, but early efforts to demonstrate this for ITC data indicated significant inconsistency. In an extensive 2004 study of the Ba2+ + 18-crown-6 ether complexation used in prior comparisons, Mizoue and Tellinghuisen found modest (10-20%) but statistically significant differences, which were tentatively attributed to problems converting the calorimetric estimates to their standard state values, as implied by the superscript ° in the notation. In the present work the 2004 results are reanalyzed using results obtained since then from temperature, heat, and volume calibration of the instrument and a better determination of the data variance function required for the weighted least-squares fitting of the data. The new results show consistency for temperatures 5-30 °C but persistent statistically significant differences from 35 to 46 °C. Several possible explanations for the remaining discrepancies are examined, with methods that include fitting the K and ΔHcal data together.


Asunto(s)
Bario/química , Calorimetría , Éteres Corona/química , Termodinámica , Calibración
15.
Sci Rep ; 11(1): 23422, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34873260

RESUMEN

Cadmium (Cd) as a toxic element that is widely present in water, soil, and air has important effects on human health, therefore proposing an accurate and selective method for detection of this element is of importance. In this article, by employing full atomistic molecular dynamics (MD) simulations and density functional theory dispersion corrected (DFT-D3) calculations, the effects of 6-mercaptonicotinic acid (MNA) and L-cysteine (CYS) on the stability of gold nanoparticles (AuNPs) and their sensitivity against Cd2+ were investigated. The obtained results indicate that pure AuNPs are not stable in water, while functionalized AuNPs with CYS and MNA groups have considerable stability without aggregation. In other words, the functional groups on the surface of AuNPs elevate their resistance against aggregation by an increase in the repulsive interactions between the gold nanoparticles. Moreover, functionalized AuNPs have considerable ability for selective detection of Cd2+ in the presence of different metal ions. Based on the MD simulation results, MNA-CYS-AuNPs (functionalized AuNPs with both functional groups) have the maximum sensitivity against Cd2+ in comparison with MNA-AuNPs and CYS-AuNPs due to the strong electrostatic interactions. DFT-D3 calculations reveal that the most probable interactions between the metal ions and functional groups are electrostatic, and Cd2+ can aggregate functionalized AuNPs due to strong electrostatic interactions with MNA and CYS groups. Moreover, charge transfer and donor-acceptor analyses show that molecular orbital interactions between the functional groups and Cd2+ can be considered as the driving force for AuNPs aggregation. A good agreement between the theoretical results and experimental data confirms the importance of the molecular modeling methods as a fast scientific protocol for designing new functionalized nanoparticles for application in different fields.


Asunto(s)
Cadmio/análisis , Oro/química , Nanopartículas del Metal/química , Nanotecnología/métodos , Ácidos Nicotínicos/química , Contaminantes Químicos del Agua/análisis , Bario/química , Colorimetría , Cisteína/química , Iones , Límite de Detección , Modelos Moleculares , Simulación de Dinámica Molecular , Niacina/química , Teoría Cuántica , Solventes , Electricidad Estática , Termodinámica , Agua
16.
Int J Mol Sci ; 22(23)2021 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-34884843

RESUMEN

X-ray photodynamic therapy (XPDT) has been recently considered as an efficient alternative to conventional radiotherapy of malignant tissues. Nanocomposites for XPDT typically consist of two components-a nanophosphor which re-emits X-rays into visible light that in turn is absorbed by the second component, a photosensitizer, for further generation of reactive oxygen species. In this study, BaGdF5 nanophosphors doped with different Eu:Gd ratios in the range from 0.01 to 0.50 were synthesized by the microwave route. According to transmission electron microscopy (TEM), the average size of nanophosphors was ~12 nm. Furthermore, different coatings with amorphous SiO2 and citrates were systematically studied. Micro-CT imaging demonstrated superior X-ray attenuation and sufficient contrast in the liver and the spleen after intravenous injection of citric acid-coated nanoparticles. In case of the SiO2 surface, post-treatment core-shell morphology was verified via TEM and the possibility of tunable shell size was reported. Nitrogen adsorption/desorption analysis revealed mesoporous SiO2 formation characterized by the slit-shaped type of pores that should be accessible for methylene blue photosensitizer molecules. It was shown that SiO2 coating subsequently facilitates methylene blue conjugation and results in the formation of the BaGdF5: 10% Eu3+@SiO2@MB nanocomposite as a promising candidate for application in XPDT.


Asunto(s)
Bario/química , Europio/química , Gadolinio/química , Nanocompuestos/química , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Supervivencia Celular/efectos de los fármacos , Medios de Contraste/química , Cristalografía por Rayos X , Células HeLa , Humanos , Nanocompuestos/toxicidad , Tamaño de la Partícula , Fármacos Fotosensibilizantes/farmacología , Dióxido de Silicio/química , Rayos X
17.
J Mater Chem B ; 9(33): 6691-6702, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34382634

RESUMEN

Hydroxyapatite (HA) is the most commonly used orthopedic implant material. In recent years, the emergence of cationic doped hydroxyapatite has revealed more possibilities for the biological application of HA. Conventional HA does not promote new bone formation because of its poor osteoinductive activity, and has a similar density to that of bone, leading to difficulty in distinguishing both via imaging. Magnesium ions are useful for regulating the cellular behavior and promoting bone regeneration. Ba ion related compounds, such as BaSO4, have a strong X-ray shielding effect. In this study, Ba/Mg@HA was synthesized to prepare Ba/Mg@HA/PLGA composites, and we aimed to investigate if Ba/Mg@HA/PLGA composites enhanced bone repair on osteoblasts and tibial defects, as well as the X-ray and CT imaging ability of bone implants in rats. The in vitro experimental results showed that the Ba/Mg@HA/PLGA composites significantly improved the attachment and osteogenic differentiation of MC3T3-E1 cells. These include the promotion of mineral deposition, enhancement of alkaline phosphatase activity, upregulation of OCN and COL-1 gene expression, and increase in COL-1 and OCN protein expression in a time- and concentration-dependent manner. The in vivo experimental results showed that the Ba/Mg@HA/PLGA composites significantly increased the rate of bone defect healing and the expression of BMP-2 and COL-1 in the bones of rats. X-ray and CT imaging results showed that the Ba/Mg@HA/PLGA composites enhanced the X-ray imaging ability. These findings indicate that the Ba/Mg@HA/PLGA composites can effectively promote bone formation and improve the X-ray and CT imaging abilities to a certain extent.


Asunto(s)
Bario/farmacología , Materiales Biocompatibles/farmacología , Regeneración Ósea/efectos de los fármacos , Durapatita/farmacología , Magnesio/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Células 3T3 , Animales , Bario/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Células Cultivadas , Durapatita/química , Magnesio/química , Masculino , Ensayo de Materiales , Ratones , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratas , Ratas Sprague-Dawley , Tomografía Computarizada por Rayos X , Rayos X
18.
Bioprocess Biosyst Eng ; 44(9): 1957-1964, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33934243

RESUMEN

The aim of this study was cost-effective and greener synthesis of barium carbonate (BaCO3 or witherite) nanoparticles with economic importance, and to evaluate their therapeutic potentials and biocompatibility with immune cells. Barium carbonate nanoparticles were biosynthesized using black elderberry extract in one step with non-toxic precursors and simple laboratory conditions; their morphologies and specific structures were analyzed using field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (FESEM-EDX). The therapeutic capabilities of these nanoparticles on the immune cells of murine macrophages J774 and promastigotes Leishmania tropica were evaluated. BaCO3 nanoparticles with IC50 = 46.6 µg/mL were more effective than negative control and glucantium (positive control) in reducing promastigotes (P < 0.01). Additionally, these nanoparticles with a high value of cytotoxicity concentration 50% (CC50) were less toxic to macrophage cells than glucantime; however, they were significantly different at high concentrations compared to the negative control.


Asunto(s)
Antiprotozoarios , Bario , Carbonatos , Leishmania tropica/crecimiento & desarrollo , Macrófagos , Ensayo de Materiales , Animales , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Antiprotozoarios/farmacología , Bario/química , Bario/farmacología , Carbonatos/química , Carbonatos/farmacología , Línea Celular , Macrófagos/metabolismo , Macrófagos/parasitología , Ratones , Nanopartículas/química , Nanopartículas/uso terapéutico , Extractos Vegetales/química , Sambucus/química
19.
Sensors (Basel) ; 21(2)2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33445501

RESUMEN

This research paper is concentrated on the design of biologically compatible lead-free piezoelectric composites which may eventually replace traditional lead zirconium titanate (PZT) in micromechanical fluidics, the predominantly used ferroelectric material today. Thus, a lead-free barium-calcium zirconate titanate (BCZT) composite was synthesized, its crystalline structure and size, surface morphology, chemical, and piezoelectric properties were analyzed, together with the investigations done in variation of composite thin film thickness and its effect on the element properties. Four elements with different thicknesses of BCZT layers were fabricated and investigated in order to design a functional acoustophoresis micromechanical fluidic element, based on bulk acoustic generation for particle control technologies. Main methods used in this research were as follows: FTIR and XRD for evaluation of chemical and phase composition; SEM-for surface morphology; wettability measurements were used for surface free energy evaluation; a laser triangular sensing system-for evaluation of piezoelectric properties. XRD results allowed calculating the average crystallite size, which was 65.68 Å3 confirming the formation of BCZT nanoparticles. SEM micrographs results showed that BCZT thin films have some porosities on the surface with grain size ranging from 0.2 to 7.2 µm. Measurements of wettability showed that thin film surfaces are partially wetting and hydrophilic, with high degree of wettability and strong solid/liquid interactions for liquids. The critical surface tension was calculated in the range from 20.05 to 27.20 mN/m. Finally, investigations of piezoelectric properties showed significant results of lead-free piezoelectric composite, i.e., under 5 N force impulse thin films generated from 76 mV up to 782 mV voltages. Moreover, an experimental analysis showed that a designed lead-free BCZT element creates bulk acoustic waves and allows manipulating bio particles in this fluidic system.


Asunto(s)
Acústica/instrumentación , Materiales Biocompatibles/química , Cerámica/química , Circonio/química , Bario/química , Electroforesis/métodos , Diseño de Equipo , Glicerol/química , Plomo , Microscopía Electrónica de Rastreo , Aceite de Oliva/química , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
20.
Int J Mol Sci ; 21(20)2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-33066665

RESUMEN

This study investigates combining the good biocompatibility and flexibility of silk protein with three types of widely used magnetic nanoparticles to comparatively explore their structures, properties and potential applications in the sustainability and biomaterial fields. The secondary structure of silk protein was quantitatively studied by infrared spectroscopy. It was found that magnetite (Fe3O4) and barium hexaferrite (BaFe12O19) can prohibit ß-sheet crystal due to strong coordination bonding between Fe3+ ions and carboxylate ions on silk fibroin chains where cobalt particles showed minimal effect. This was confirmed by thermal analysis, where a high temperature degradation peak was found above 640 °C in both Fe3O4 and BaFe12O19 samples. This was consistent with the magnetization studies that indicated that part of the Fe in the Fe3O4 and BaFe12O19 was no longer magnetic in the composite, presumably forming new phases. All three types of magnetic composites films maintained high magnetization, showing potential applications in MRI imaging, tissue regeneration, magnetic hyperthermia and controlled drug delivery in the future.


Asunto(s)
Materiales Biocompatibles/química , Fibroínas/química , Nanopartículas de Magnetita/química , Bario/química , Materiales Biocompatibles/normas , Cobalto/química , Hierro/química , Nanopartículas de Magnetita/clasificación , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta
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