BaSO4 Nanoparticles Research Articles

Immobilized Drugs on Dual-Mode Imaging Ag2S/BaSO4/PVA Embolic Microspheres for Precise Localization, Rapid Embolization, and Local Antitumor Therapy.

Transcatheter arterial embolization (TAE) in interventional therapy and tumor embolism therapy plays a significant role. The choice of embolic materials that have good biocompatibility is an essential component of TAE. For this study, we produced a multifunctional PVA embolization material that can simultaneously encapsulate Ag2S quantum dots (Ag2S QDs) and BaSO4 nanoparticles (BaSO4 NPs), exhibiting excellent second near-infrared window (NIR-II) fluorescence imaging and X-ray imaging, breaking through the limitations of traditional embolic microsphere X-ray imaging. To improve the therapeutic effectiveness against tumors, we doped the doxorubicin (DOX) antitumor drug into microspheres and combined it with a clotting peptide (RADA16-I) on the surface of microspheres. Thus, it not only embolizes rapidly during hemostasis but also continues to release and accelerate tumor necrosis. In addition, Ag2S/BaSO4/PVA microspheres (Ag2S/BaSO4/PVA Ms) exhibited good blood compatibility and biocompatibility, and the results of embolization experiments on renal arteries in rabbits revealed good embolic effects and bimodal imaging stability. Therefore, they could serve as a promising medication delivery embolic system and an efficient biomaterial for arterial embolization. Our research work achieves the applicability of NIR-II and X-ray dual-mode images for clinical embolization in biomedical imaging.

Spectroscopic and non-spectroscopic analysis of Fe-substituted BaSO4 nanoparticles by chemical precipitation method

Spectroscopic and non-spectroscopic analysis of Fe-substituted BaSO4 nanoparticles by chemical precipitation method

Underoil superhydrophilic flame-retardant 3D porous composite for efficient on-demand emulsion separation: Interface engineering design on sphagnum moss

Oil pollution and the energy crisis make oil-water separation an urgent for human need. The widespread use of materials with a single emulsion separation capability is limited. Multifunctional on-demand separation materials can adapt to a wide range of application scenarios, thus having a wider range of applications. The underoil superhydrophilic surface is of great significance for realizing the on-demand separation of oil/water emulsions through the removal of water in the oil and oil in the water. A 3D porous emulsion separation material based on the superhydrophilic principle of sphagnum moss was designed. The material was prepared in a simple step by taking advantage of the adhesion of polydopamine and the introduction of the as-prepared superhydrophilic BaSO4 nanoparticles to achieve superhydrophilicity with a water contact angle (WCA) of 0° and an oil contact angle (OCA) of 157.3°, resulting in excellent separation performance for both water-in-oil and oil-in-water emulsions. Underoil superhydrophilic porous composite (OSPC) can complete two kinds of emulsion separations by filtration or adsorption. It adsorbs water from water-in-oil emulsion to achieve separation, with a good adsorption capacity of 74.38 g/g and efficiency up to 99%. It can also filter oil-in-water emulsions with an efficiency of 99.92%. The separation efficiencies are all almost unchanged after ten separation cycles. Furthermore, the material has excellent flame retardancy, which reduces the possibility of secondary disasters. The three-dimensional porous sponge has excellent on-demand separation performance for multiple emulsions. It provides a new preparation strategy for underoil superhydrophilic materials and a new idea for the design direction of special wetting materials for the on-demand separation of oil/water emulsions.

Unbaffled mesoscale reactor coupled oscillatory flow-enhanced liquid–solid two–phase flow

Unbaffled U-shaped mesoscale oscillatory flow reactors (meso-OFRs) were developed to prevent solid deposition and prepare uniform barium sulfate (BaSO4) nanoparticles with environmental protection function. The results showed that the oscillation significantly reduced granular deposition; the greater the intensity of the oscillation, the faster it reached uniformity, and the less likely the granules were to be deposited. These results can be explained by the formation of a larger vortex size, which can strengthen the turbulent mixing of fluid in the reactor, promote the interaction and forced mixing between the liquid phase and solid particles, enhance the internal shear stress of the fluid, and contribute to the secondary suspension of solid particles and the disintegration of particle agglomeration. The prepared BaSO4 nanoparticles with oscillation were smaller in size and lower in pressure drop than those produced without oscillation, which conclusively illustrated that oscillation effectively prevented channel deposition and clogging.

BaSO4-Epoxy Resin Composite Film for Efficient Daytime Radiative Cooling.

Conventional cooling methods are based on active cooling technology by air conditioning, which consumes a large amount of energy and emits greenhouse gases. Radiative cooling is a novel promising passive cooling technology that uses external space as the cooling source and requires no additional energy consumption. Herein, we propose an approach to prepare highly dispersed BaSO4 nanoparticles (NPs) using a direct precipitation method combined with the in situ surface modification technology. The as-prepared PVP-modified BaSO4 NPs with an average size of 20 nm can be stably dispersed in ethanol for more than 6 months and then were used as building blocks to prepare spherical BaSO4 clusters with an average size of 0.9 μm using a scalable spray drying technique. The BaSO4 NPs/clusters (mass ratio 1:1) were used for preparing radiative cooling epoxy resin film, showing a high solar reflectance of 71% and a high sky window emissivity of 0.94. More importantly, this composite film displays superior radiative cooling performance, which can reduce the ambient temperature by 13.5 °C for the indoor test and 7 °C for the outdoor test. Compared with the commercial BaSO4 filled film, our BaSO4-epoxy resin composite film offers advantages not only in radiative cooling but also in mechanical properties with a 16.6% increase of tensile strength and 40.1% increase of elongation at break, demonstrating its great application potential in the field of building air conditioning.

A new method in the production of protective sheets against X-ray radiation

Today, the use of X-rays in diagnosing and sometimes treating patients is inevitable. Despite the many benefits of using X-rays in medical and other sciences, the harmful effects of this radiation on human tissue should not be neglected. One of the best ways to prevent the harmful effects of X-rays on the human body is to use appropriate covers against these rays. It seems that it is necessary to find effective particles to weaken X-rays and choose a suitable substrate with high mechanical resistance to scatter particles in it. In this study, the synthesis of SnO2 nanoparticles from SnCl2.2H2O precursor and BaSO4 nanoparticles from BaCl2.2H2O precursor using neem tree extract (Azadirachta indica) as a reducing and stabilizing agent is reported. After the synthesis of nanoparticles, their structure was investigated by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. Then the desired composite and nanocomposite were prepared in the polymer substrate. The sheets were prepared using an extruder and then a hot hydraulic press. The output sheets had a thickness of 1 mm. The structural characteristics of the produced sheets such as surface morphology, density of prepared composites, mechanical properties, thermal gravimetric analysis and retention of loaded particles after three times washes were investigated. The X-ray attenuation capability of each sample was evaluated by calculating the linear attenuation coefficient for each prepared sample. The results show that all sheets filled with tin and barium micro and nano particles have more X-ray attenuation capabilities than pure polymer. Among the prepared sheets, the nanocomposite prepared from low-density polyethylene (77 %) + SnO2 (10 %) + BaSO4 (10 %) + multi-walled carbon nanotubes (3 %) showed the highest X-ray attenuation.

Alternative Polyurethane/Gutta-Percha/ZnO Biocomposite for Root Canal Therapy Based on an Efficient Melt Extrusion Additive Manufacturing Strategy

This work aims to investigate dental root filling custom gutta-percha (GP) properties based on melt extrusion 3D printing for periapical periodontal disease treatment. Zinc oxide nanoparticles are incorporated into polyurethane/gutta-percha (PGB) composites. A polyurethane/gutta-percha/ZnO (PGB-Zn) biocomposite including BaSO4, polyurethane (PU), GP, and ZnO nanoparticles is designed and fabricated. To improve the dispersion of ZnO nanoparticles, rosin is chosen to modify the surface of the ZnO nanoparticles. The PGB-Zn biocomposite exhibits a maximum tensile strength of 26.795 ± 1.173 MPa and a flexural strength of 6.037 ± 0.37 MPa. The chemical interaction between the nanoparticles and the matrix is found in the physical and mechanical characterization of the polyurethane/gutta-percha/ZnO (PGB-Zn) biocomposite. The inhibition zone test and absorbance photometry show that the composite material inhibits and kills Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The CCK-8 experimental results show that the PGB-Zn biocomposite has a cytotoxicity level of 0-I. The obtained PGB-Zn biocomposite in this work can be used for accurate root canal therapy as a filling biocomposite by a fused extrusion method, which effectively decreases the potential risk of the clinical implementation of periapical periodontal disease treatment.

Microflow precipitation of barium sulfate nanoparticles from mineral barium sulfide black ash

Microflow precipitation reaction is an effectively method for preparing high quality nanoparticles. In this study, BaSO4 nanoparticles were successfully prepared from BaS black ash in a simple capillary microreactor. Two important microflow parameters, feed flow velocity and residence time, on morphology, structure, component, average particle size (dav) and coefficient of variation (CV) of the as-synthesized product are investigated. The results show that well-dispersed ellipsoidal nanoparticles of BaSO4 with purity >99 wt% can be prepared using this novel method. High flow velocity is beneficial for producing small particles with low CV, and short residence time is also good for slightly small particles but with high CV. The dav and CV values are in the range of 33.8∼53.5 nm and 0.32∼0.39, respectively. In addition, the preparation of the BaSO4 product by this new method is compared with those by precipitation in other typical reactors. Combined with the simplicity of the microchannel structure, continuity of process operation and atomic economy of the raw materials, this proposed method is effective for preparing high quality BaSO4 nanoparticles with narrow particle size distribution.

Green-Manufactured and Recyclable Coatings for Subambient Daytime Radiative Cooling.

Passive daytime radiative cooling, which reflects sunlight and simultaneously emits heat into space to cool surfaces without energy input, is a promising strategy for energy conservation. Integrating radiative cooling with building systems can tremendously alleviate electrical cooling, but manufacturing high-efficient and eco-friendly coatings remains an urgent and challenging task. Here, we present a simple and scale-up strategy for fabricating ultrawhite coatings consisting of porous ethyl cellulose matrix-random BaSO4 nanoparticles utilizing green solvents. With the synergistic effect of the ideal intrinsic properties of the materials and the strong Mie scattering of the porous structure, the ultrawhite coating possesses a record solar reflectance of 98.6% and a thermal emittance of 98.1%, resulting in a subambient temperature drop of over 2.5 °C under a solar intensity of ∼920 W m-2. Better yet, our coatings can be conveniently brushed, rolled, or sprayed onto various types of substrates, with excellent durability, self-cleaning, and cost-effectiveness, paving an attractive and viable pathway for large-scale applications in practical buildings.

A high‐throughput chaotic advection microreactor for preparation of uniform and aggregated barium sulfate nanoparticles

AbstractA high‐throughput (105.5 g/h) passive four‐stage asymmetric oscillating feedback microreactor using chaotic mixing mechanism was developed to prepare aggregated Barium sulfate (BaSO4) particles of high primary nanoparticle size uniformity. Three‐dimensional unsteady simulations showed that chaotic mixing could be induced by three unique secondary flows (i.e., vortex, recirculation, and oscillation), and the fluid oscillation mechanism was examined in detail. Simulations and Villermaux–Dushman experiments indicate that almost complete mixing down to molecular level can be achieved and the prepared BaSO4 nanoparticles were with narrow primary particle size distribution (PSD) having geometric standard deviation, σg, less than 1.43 when the total volumetric flow rate Qtotal was larger than 10 ml/min. By selecting Qtotal and reactant concentrations, average primary particle size can be controlled from 23 to 109 nm as determined by microscopy. An average size of 26 nm with narrow primary PSD (σg = 1.22) could be achieved at Qtotal of 160 ml/min.

Flexible gamma ray shielding based on natural Rubber/BaSO4 nanocomposites

This study aims to fabricate lead-free, flexible gamma ray shielding based on natural rubber (NR) with the original-sized barium sulphate (BaSO4) and BaSO4 nanocomposites. The shielding composites were successfully fabricated with various fillers loading of 10, 20, 30 and 50 parts per hundred rubbers (phr). The physical and mechanical properties of the NR composites have been investigated. The gamma ray shielding properties were measured with 57Co (122.06 keV) and 133Ba (356.02 keV) sources. Our results indicated that additional filler concentrations into NR increased density, hardness (shore A), tensile modulus, tensile strength, and elongation at break of NR. Tensile properties and elongation at break of NR with BaSO4 nanoparticles were slightly lower than the ordinary-sized BaSO4. For the gamma ray shielding properties, the linear attenuation coefficient (μ) mass attenuation coefficient (μm) were increased with the increasing of fillers concentrations. The half value layer (HVL) was decreased with the increasing of BaSO4 and BaSO4 nanoparticles in NR. In comparison of shielding properties between NR with BaSO4 nanoparticles and the ordinary-sized BaSO4 showed that the NR with nanocomposites provided better gamma radiation shielding due to the large surface to volume area of nanocomposites. In conclusion, the novel developed shielding based on NR/BaSO4 nanocomposites showed a promising result for developing potential radiation shielding due to their flexibility, lightweight and lead-free shielding material.

Recent Advances in the Preparation of Barium Sulfate Nanoparticles: A Mini-Review

The potential for barium sulphate nanoparticles to be used in a variety of important fields has sparked a lot of attention. Methods for obtaining this material by milling (top-down approach) are not very popular due to the difficulty of controlling the size and shape of particles, as well as changes in their physicochemical properties during milling. More promising is the bottom-up approach, which is the interaction of Ba2+ and SO42− ions in a liquid environment. Direct precipitation is the simplest method; however, it does not allow control of the particle size. Microemulsions, microreactors membrane dispersion, as well as spinning disc reactors are used to overcome drawbacks of direct precipitation and allow control of particle size and shape. This is ensured mainly by intensive controlled micromixing of the precursors with concentrations close to saturated ones. The present review focuses on recent advances in the production of barium sulfate nanoparticles using various approaches, as well as their advantages and limitations. The issues of scaling up the techniques are also considered, and promising methods for obtaining BaSO4 nanoparticles are also discussed.

Synthesis and Characterization of BaSO4-CaCO3-Alginate Nanocomposite Materials as Contrast Agents for Fine Vascular Imaging.

Microcomputed tomography is an important technique for distinguishing the vascular network from tissues with similar X-ray attenuation. Here, we describe a composite of barium sulfate (BaSO4) nanoparticles, calcium carbonate (CaCO3) nanoparticles, and alginate that provides improved performance over microscale BaSO4 particles, which are currently used clinically as X-ray contrast agents. BaSO4 and CaCO3 nanoparticles were synthesized using a polyol method with tetraethylene glycol as solvent and capping agent. The nanoparticles show good colloidal stability in aqueous solutions. A deliverable nanocomposite gel contrast agent was produced by encapsulation of the BaSO4 and CaCO3 nanoparticles in an alginate gel matrix. The gelation time was controlled by addition of d-(+)-gluconic acid δ-lactone, which controls the rate of dissolution of the CaCO3 nanoparticles that produce Ca2+ which cross-links the gel. Rapid cross-linking of the gel by Ba2+ was minimized by producing BaSO4 nanoparticles with an excess of surface sulfate. The resulting BaSO4-CaCO3 nanoparticle alginate gel mechanical properties were characterized, including the gel storage modulus, peak stress and elastic modulus, and radiodensity. The resulting nanocomposite has good viscosity control and good final gel stiffness. The nanocomposite has gelation times between 30 and 35 min, adequate for full body perfusion. This is the first nanoscale composite of a radiopaque metal salt to be developed in combination with an alginate hydrogel and designed for medical perfusion and vascular imaging applications.

Ultrawhite BaSO4 Paints and Films for Remarkable Daytime Subambient Radiative Cooling.

Radiative cooling is a passive cooling technology that offers great promises to reduce space cooling cost, combat the urban island effect, and alleviate the global warming. To achieve passive daytime radiative cooling, current state-of-the-art solutions often utilize complicated multilayer structures or a reflective metal layer, limiting their applications in many fields. Attempts have been made to achieve passive daytime radiative cooling with single-layer paints, but they often require a thick coating or show partial daytime cooling. In this work, we experimentally demonstrate remarkable full-daytime subambient cooling performance with both BaSO4 nanoparticle films and BaSO4 nanocomposite paints. BaSO4 has a high electron band gap for low solar absorptance and phonon resonance at 9 μm for high sky window emissivity. With an appropriate particle size and a broad particle size distribution, the BaSO4 nanoparticle film reaches an ultrahigh solar reflectance of 97.6% and a high sky window emissivity of 0.96. During field tests, the BaSO4 film stays more than 4.5 °C below ambient temperature or achieves an average cooling power of 117 W/m2. The BaSO4-acrylic paint is developed with a 60% volume concentration to enhance the reliability in outdoor applications, achieving a solar reflectance of 98.1% and a sky window emissivity of 0.95. Field tests indicate similar cooling performance to the BaSO4 films. Overall, our BaSO4-acrylic paint shows a standard figure of merit of 0.77, which is among the highest of radiative cooling solutions while providing great reliability, convenient paint form, ease of use, and compatibility with the commercial paint fabrication process.

Preparation of transparent BaSO4 nanodispersions by high-gravity reactive precipitation combined with surface modification for transparent X-ray shielding nanocomposite films

BaSO4 nanoparticles as important functional materials have attracted considerable research interests, due to their X-rays barrier and absorption properties. However, most of BaSO4 nanoparticles prepared by traditional technology are nanopowders with broad size distribution and poor dispersibility, which may greatly limit their applications. To the best of our knowledge, the synthesis of transparent BaSO4 nanodispersions was rarely reported. Here, we firstly present a novel and efficient method to prepare transparent and stable BaSO4 nanodispersions with a relatively small particle size around 10 to 17 nm using a precipitation method in a rotating packed bed (RPB), followed by a modification treatment using stearic acid. Compared with the BaSO4 prepared in a traditional stirred tank, the product prepared using an RPB has much smaller particle size and narrower size distribution. More importantly, by using RPB, the reaction time can be significantly decreased from 20 min to 18 s. Furthermore, the transparent BaSO4-polyvinyl butyral nanocomposite films with good X-ray shielding performance can be easily fabricated. We believe that the stable BaSO4 nanodispersions may have a wide range of applications for transparent composite materials and coatings with X-ray shielding performance for future research.

The preparation and characterization of silicon-based composites doped with BaSO4, WO3, and PbO nanoparticles for shielding applications in PET and nuclear medicine facilities

Objective(s): The present study aimed to design new nanoparticle-based shielding materials for photons used in single-photon emission computed tomography and positron emission tomography facilities. Materials and Methods: Initially, the mass attenuation coefficients and half value layer (HVL) of the composites were comprehensively investigated based on a silicon rubber containing various ratios of micro- and nano-barium sulfate (BaSO4), lead oxide (PbO), and tungsten oxide (WO3) particles at 60, 80, 100, 150, 200, 300, 400, 500, and 600 keV photon energies using the MCNP-X6 Monte Carlo (MC) code and WinXCOM software. In the second stage, the composites composed of 10 wt% and 20 wt% WO3 and PbO particles were constructed in a liquid silicone rubber-based matrix. The mass attenuation coefficients and HVL of the designed shields were experimentally assessed using Cs-137 and Am-241 radioactive sources.Results: The particles sizes of PbO and WO3 were within the range of 50-200 nanometers. The MC and measurement results indicated that the linear attenuation coefficients of the composites were augmented with the addition of all the studied nano- and micro-particles. However, the PbO composites had more significant shielding properties compared to the BaSO4 and WO3 composites. Conclusion: According to the results, the nanocomposites had better ability to shield γ-rays at both energies compared to the micro-composites.

Metal-Doped Barium Sulphate Nanoparticles Decorated with Gelatin as Antibacterial Agents

Nanoparticles are gaining a new impetus in the field of medicine because of their potential to overcome core problems of drug efficacy. Amongst inorganic nanoparticles, barium sulphate in nano form is achieving wide attention due to its valuable applications. Despite the several advantages of barium sulphate nanoparticles, there is a major difficulty in their preparation and stability in the medium, as they belong to poorly soluble particles group. Hence, bearing in mind the synthesis barriers associated with these nanoparticles, a modified methodology has been designed for the synthesis of nanoparticles by capping them with gelatin. In addition, to enhance their physico-chemical properties and antimicrobial efficacy, BaSO4 nanoparticles were doped with four different metals. The synthesized nanoparticles were characterized through UV–Visible spectra, X-Ray Diffraction patterns, Dynamic Light Scattering, Field Emission Scanning Electron Microscopy analysis. Their antimicrobial potential and cytotoxicity through mitogenic response was also evaluated. These doped nanoparticles have shown enhanced properties in their structure (size reduction from micro to nano, dispersibility in the medium, non-aggregation etc.) and antimicrobial efficiency than its bulk counterparts. To the best of our knowledge, this is the first report on antimicrobial potential of synthesized metal-doped barium sulphate nanoparticles stabilized with gelatin.

Static-guided fabrication, characterization and antistatic property of BaSO4@sulfonated-graphene conductive fillers

Sulfonated Graphene (GS) is a kind of ideal conductive filler due to its excellent electrical conductivity, large specific surface and high dispersion. However, it usually has a tendency to agglomerate in polymers which seriously weaken the antistatic property. Herein, a novel conductive filler was fabricated in a simple and low-cost method by self-assembling GS nanosheets onto the surface of BaSO4 nanoparticles (BaSO4@GS) through electrostatic attraction. The morphology, microstructural composition and antistatic property were studied. The conductive BaSO4@GS particles have greatly dispersion in the epoxy resin matrix and significantly decrease square resistance of coating. The results show that the addition of 2 wt% (GS content in the epoxy composite) BaSO4@GS nanoparticles can decrease sheet resistance to 32 KΩ/sq. We attribute this enhancement in conductive performance of the epoxy composite to construction of the conductive networks for BaSO4@GS additives. Thus, the conductive fillers show the great potential for application in the petrochemical industry.

Fate of Barium Sulfate Nanoparticles Deposited in the Lungs of Rats

We have shown that barium [from BaSO4 nanoparticles (NPs)] was cleared from the lungs faster than other poorly soluble NPs and translocated mostly to bone. We now studied barium biokinetics in rats during Study 1: two-year inhalation exposure to 50 mg/m3 BaSO4 NP aerosols, and Study 2: single intratracheal (IT) instillation of increasing doses of BaSO4 NPs or BaCl2. Study 1 showed that lung barium content measured by inductively coupled plasma mass spectrometry increased during 360 days of BaSO4 NP aerosol exposures. An equilibrium was established from that time until 2 years. Barium concentrations in BaSO4-exposed animals were in the order (lungs > lymph nodes > hard bone > bone marrow > liver). In Study 2, there was an increase in lung barium post-IT instillation of BaSO4 NPs while barium from BaCl2 was mostly cleared by day 28. Transmission electron microscopy showed intact BaSO4 NPs in alveolar macrophages and type II epithelial cells, and in tracheobronchial lymph nodes. Using stimulated Raman scattering microscopy, specific BaSO4 Raman spectra were detected in BaSO4 NP-instilled lungs and not in other organs. Thus, we posit that barium from BaSO4 NPs translocates from the lungs mainly after dissolution. Barium ions are then incorporated mostly into the bone and other organs.

Synthesis and Nucleation Mechanism Recognition of BaSO4 Nanoparticle in the Presence of Biopolymers

A major portion of BaSO4 is used as drilling fluid additives in the presence of some biopolymers such as starch and PAC (Polyanionic Cellulose) as filtration control and viscosifier. BaSO4 nanoparticle was synthesized in the presence of these applicable polymers with precipitation method by using BaS produced from carbothermal method and Na2SO4. Synthesized nanoparticles size and morphology were analyzed using DLS (Dynamic Light Scattering) and FESEM (Field Emission Scanning Electron Microscope). It can be concluded that, nanoparticles size have inverse proportion with polymer concentration. Also nanoparticles have smaller size in the presence of PAC with longer functional group than starch and prevent chemical reaction due to steric hindrance. If pH increases from 7 to 11, nanoparticles in starch had minimum size in pH=9 and various pH didn’t have noticeable effect on size with PAC. In kinetic study, conductometer is used to detect induction time in different Na2SO4 concentrations and polymers and it is indicated that interfacial tension is decreased as reactant concentration increased and PAC increase induction time and reduce interfacial tension more than starch.