Submicron Particles Research Articles

Color‐Tunable Luminescence of Eu‐Doped LaF3 Particles Sensitized by d–f Energy Transfer from a Two‐Photon Absorbing Ir(III) Complex

AbstractThe surface of Eu0.3La0.7F3 submicron particles is functionalized with a blue‐emitting Ir(III) complex (1) specifically designed to coordinate lanthanide(III) ions efficiently through a carboxylic unit. In this Eu0.3La0.7F3@1 composite, the Ir(III) complexes are randomly coordinated to either superficial La(III) ions or Eu(III) ions (Ir‐Lasurface and Ir‐Eusurface pairs, respectively) and its color emission, a balance between blue (Ir‐based) and red (Eu‐based) light, can be tuned as a function of the excitation wavelength. Irradiation at the maximum of the excitation band in 1 promotes blue emission from Ir‐Lasurface pairs and red emission from Eusurface ions sensitized by Ir → Eusurface energy transfer (EnT). At λexc = 396 nm (maximum of the Eu(III) 5L6 ← 7F0 absorption band) the red emission from inner Eu(III) ions becomes dominant. Excitation of 1 can also be achieved by two photon‐absorption (TPA) since this complex has a moderate cross‐section of σ2 = 9.4 ± 1.0 GM at 780 nm (σ2 = 5.8 ± 0.6 GM at 800 nm). Phosphorescence lifetime imaging (PLIM) allows the emission of individual particles to be visualized and the Ir‐, Eusurface‐, and Eucore‐based emissions can be distinguished due to the significant differences in their respective emission lifetimes.

Material representativeness of a polymer matrix doped with nanoparticles as the random speckle pattern for digital volume correlation of fibre-reinforced composites

Combining tomographic imaging with digital volume correlation allows in-situ 3D strain mapping, leading to a quantitative assessment of damage mechanisms and associated material properties in structural materials. Being based on pattern recognition, digital volume correlation is well-suited for materials with intrinsic and stable microstructural heterogeneity, such as certain biological tissues. Unfortunately, conventional polymers and fibre-reinforced polymer composites lack the required heterogeneity. Recently, solutions like doping the polymers with particles have been explored to overcome this limitation. The particles embedded in the polymer matrix provide a random, volumetric speckle pattern, acting as displacement trackers for the digital volume correlation algorithm. However, the particles might influence the mechanical and rheological behaviour of the polymer, which is detrimental in investigations of the composite material properties. This paper investigates the mechanical, mechanistic, and rheological representativeness of an epoxy doped with two types of sub-micrometre particles optimised for digital volume correlation. Since particle dispersion is considered a key driver for representativeness, we simultaneously quantitatively assess the dispersion by combining scanning electron microscopy and X-ray computed tomography.

The impact of chlorine and sulfur on alkali metal migration and submicron particle formation during solid fuel combustion

Submicron particles (PM1) emission from the incineration of solid fuels rich in chlorine, sulfur, or alkali metal elements pose environmental and health concerns for humans. The current understanding of the interactions between these elements and PM1 formation is extensive, but it still lacks a systematic approach. This paper establishes a comprehensive model to predict the migration process of Cl, S, and alkali metals during solid fuel combustion by adding Cl, S, and K additives. The model is divided into combustion, vaporization, nucleation and condensation, and coagulation sub-models. The model predicts that K, Cl, and S additives will not cause changes in fuel's burnout time and temperature. While these additives each promotes the vaporization rate of sodium to varying degrees, for example, the vaporization rate with +K + S is much lower than with +K + Cl. Also, the model calculates that the addition of SO2 significantly inhibits the formation of KCl. In the Sufco + K condition, introducing SO2 reduces the concentration of KCl by about 80%, but if Cl is added, the concentration increases by approximately four times. Predictions were also made for the changes in K2SO4, NaCl, and Na2SO4 under different conditions. After adding K, Cl, and S, the production of PM1 significantly increased, and the peak shifted towards larger size with +K + Cl producing more PM1. Overall, the predicted results align well with the experimental findings. The model's systematic construction of the interactions between chlorine, sulfur, and alkali metal elements and the formation mechanism of PM1 provides a more complete picture of solid fuel combustion emissions.

Multi-scale characterization of submicronic NASICON-type solid electrolyte Li1.3Al0.3Ti1.7(PO4)3 degraded by spark plasma sintering

One of the most promising and developed disruptive technology of energy storage for the future is all solid-state batteries. The NASICON phase LATP (Li1.3Al0.3Ti1.7(PO4)3) is widely studied especially thanks to its high ionic conductivity and mechanical strength. However, high temperature densification is required to obtain a dense and conductive material. Here we explore the fast sintering by Spark Plasma Sintering (SPS) of submicronic LATP particles, and the impact of the heating rate on the physico-chemical and transport properties of the pristine powder. High-speed rate for the sintering process induces particles’ growth, avoiding any reduction of titanium. The impurity AlPO4 plays a major role on the conductivity, depending on its content but also on its distribution within the composite, either as a coating (surface modification) or as crystalline particles within the grain boundaries. An intimate understanding of the ceramic composites was achieved using combination of advanced characterization techniques to get a multi-scale description of the material, from the pristine to the sintered states, from the surface to the bulk, and from the atomic long range to the local scales. Sharing these fundamental results is essential, with among other motivations, the spreading of our interpretation of complex spectroscopic results (Electronic Spin Resonance (ESR) spectroscopy, solid-state Nuclear Magnetic Resonance (NMR) spectroscopy and X-ray Photoelectron Spectroscopy (XPS)), key for characterization of reactivities at interfaces in this work and in others.

A NUMERICAL ANALYSIS ON THE SUBMICRON- AND MICRON-SIZED PARTICLE SEDIMENTATION IN A WIRE-TO-PLATE ELECTROSTATIC PRECIPITATOR

Electrostatic precipitators (ESPs) are frequently utilized in collecting fine organic and inorganic materials from continuous liquid with few moving parts and high efficiency using electrically charging the particles. In this study, cross-sectional 2D geometry of a wire-to-plate electrostatic precipitator the parametric data of which originally published elsewhere was numerically modeled and validated to investigate submicron-micron particle charging in terms of diffusion and field charging mechanisms and precipitation behavior of particles with detailed electric field properties. Electric field, gas flow, and particle trajectory equations are coupled and solved in a multiphysics solver. Particle tracking is realized with the Lagrangian approach. Results indicate variations in electric field strength and space charge density between corona electrodes, with space charge present in the entire precipitation channel. Between two different charging mechanisms, diffusion charging prevails for charge accumulated on submicron particles, whereas field charging becomes dominant for particles larger than 1μm diameter. However, for the ESP configuration considered in this study, particles reach a charge saturation in less than 0.7 seconds, regardless of their size. Although calculated precipitation efficiencies for micron-sized particles can reach to 100%, efficiencies for submicron particle range drop with increasing particle size, as diffusion charging rapidly loses its effectiveness, in 50-250nm range.

Direct mitigation of secondary organic aerosol particulate pollutants by multiphase photocatalysis

Particulate matter represents one of the most severe air pollutants globally. Organic aerosol (OA) comprises 30–70 % of submicron particle mass in urban areas. An effective way to mitigate OA particulate pollutants is to reduce the formation of secondary organic aerosol (SOA). Here, we studied the effect of titanium dioxide (TiO2) photocatalytic seeds on the formation and mitigation of SOA particles from α-pinene or toluene oxidation in chamber. For the first time, we discovered that under ultraviolet (UV) irradiation, the presence of TiO2 directly removed internally mixed α-pinene SOA mass by 53.7 % within 200 mins, and also directly removed SOA matter in an externally mixed state that is not in direct contact with TiO2 surface: the mass of externally mixed α-pinene SOA was reduced by 21.9 % within 81 mins, and the toluene SOA mass was reduced by 46.6 % in 145mins. In addition, the presence of TiO2 effectively inhibited the formation of SOA particles with a SOA mass yield of zero. This study brings up an innovative concept for air pollution control - the direct photocatalytic degradation of OA with aid of TiO2-based photocatalysts. Our novel findings will potentially bring practical applications in air pollution abatement and regional, even global aerosol-climate interactions.

Green Synthesis, Characterization, Encapsulation, and Measurement of the Release Potential of Novel Alkali Lignin Micro-/Submicron Particles.

The applicability of biopolymer micro-/nano- technology in human, veterinary medicine, pharmaceutical, and food technology is rapidly growing due to the great potential of biopolymer-based particles as effective carrier systems. The use of lignin as a basic heteropolymer biomatrix for the design of innovative micro-/submicron formulations allows the achievement of increased biocompatibility and offers various active functional groups presenting opportunities for customization of the physicochemical properties and bioactivities of the formulations for diverse applications. The aim of the present study was to develop a simple and ecofriendly methodology for the synthesis of lignin particles with micro- and submicron size; to evaluate their physicochemical, spectral, and structural characteristics; and to examine their capacity for encapsulation of biologically active molecules and potential for in vitro release of bioflavonoids in simulated gastrointestinal media. The presented methodologies apply cheap and green solvents; easy, straightforward, quick, and sensitive processes requiring little equipment, non-toxic substances, and simple methods for their characterization, the determination of encapsulation capacity towards the poorly water-soluble bioactive compounds morin and quercetin, and the in vitro release potential of the lignin matrices.

The radiative and dynamical impact of clouds in the atmosphere of the hot Jupiter WASP-43 b

Context. Hot Jupiters are tidally locked gaseous exoplanets that exhibit large day-night temperature contrasts. Their cooler nightsides are thought to host clouds, as has been suggested by numerous observations. However, the exact nature of these clouds, their spatial distribution, and their impact on atmospheric dynamics, thermal structure, and spectra is still unclear. Aims. We investigate the atmosphere of WASP-43 b, a short period hot Jupiter recently observed with James Webb Space Telescope (JWST), to understand the radiative and dynamical impact of clouds on the atmospheric circulation and thermal structure. We aim to understand the impact of different kinds of condensates potentially forming in WASP-43 b, with various sizes and atmospheric metallicities. Methods. We used a 3D global climate model (GCM) with a new temperature-dependent cloud model that includes radiative feedbacks coupled with hydrodynamical integrations to study the atmospheric properties of WASP-43 b. We produced observables from our GCM simulations and compared them to spectral phase curves from various observations to derive constraints on the atmospheric properties. Results. We show that clouds have a net warming effect, meaning that the greenhouse effect caused by clouds is stronger than the albedo cooling effect. We show that the radiative effect of clouds has various impacts on the dynamical and thermal structure of WASP-43 b. Depending on the type of condensates and their sizes, the radiative-dynamical feedback will modify the horizontal and vertical temperature gradient and reduce the wind speed. For super-solar metallicity atmospheres, fewer clouds form in the atmosphere, leading to a weaker feedback. Comparisons with spectral phase curves observed with HST, Spitzer, and JWST indicate that WASP-43 b's nightside is cloudy and rule out sub-micron Mg2SiO4 cloud particles as the main opacity source. Distinguishing between cloudy solarand cloudy super-solar-metallicity atmospheres is not straightforward, and further observations of both reflected light and thermal emission are needed.

Particle surface oxidation modification and particle gradation strategy for the preparation of high-strength SiC ceramics via vat photopolymerization

The high refractive index, high absorbance, and low sintering activity of SiC powders pose challenges in achieving sufficient curing depth of SiC slurries and achieving densification of SiC ceramics. Hence, the preparation of high-strength SiC ceramics by vat photopolymerization is a challenge. This study proposes a strategy of particle surface oxidation modification and particle gradation to address this difficulty. Specifically, the surface of micron and submicron SiC particles is oxidatively modified to enhance the curing depth of SiC slurry, and the gradation of these particles is optimized to improve the sintering activity of the SiC particle system. The percentage of oxidized micron and submicron SiC particles is carefully adjusted to meet the requirements of both vat photopolymerization preparation and sintering. It found that increasing the percentage of sub-micron particles in the particle grade system had a negative impact on the rheological and curing properties of the slurry but contributed to the stability of the slurry and the performance of the sintered ceramic parts. Ensuring that the percentage of sub-micron particles reaches 50% or higher and reducing direct contact between micron particles to form sintered necks are two key conditions for the preparation of high-strength SiC ceramics. Additionally, it found that interlayer bonding location is the pore defects concentrated in the sintered ceramic parts, providing direction for further optimization of ceramic properties. By implementing the oxidation modification and particle gradation optimization strategy, the densification and three-point flexural strength of SiC ceramic parts were improved significantly. The relative density and three-point flexural strength of SiC increased from 65.7 ± 5.3% to 86.8 ± 3.7% and from 75.0 ± 2.1–170.9 ± 11.6 MPa, respectively. This approach provides a simple and effective method to prepare high-strength SiC ceramics by vat photopolymerization.

Supersaturable diacyl phospholipid dispersion for improving oral bioavailability of brick dust molecule: A case study of Aprepitant

This study aims to investigate the potential use of polymer inclusion in the phospholipid-based solid dispersion approach for augmenting the biopharmaceutical performance of Aprepitant (APT). Initially, different polymers were screened using the microarray plate method to assess their ability to inhibit drug precipitation in the supersaturated solution and HPMCAS outperformed the others. Later, the binary (BD) and ternary (TD) phospholipid dispersions were prepared using the co-solvent evaporation method. Solid-state characterization was performed using SEM and PXRD to examine the physical properties, while molecular interactions were probed through FTIR and NMR analysis. In vitro dissolution studies were performed in both fasted and fed state biorelevant media. The results demonstrated a substantial increase in drug release from BD and TD, approximately 4.8 and 9.9 times higher compared to crystalline APT in FaSSIF. Notably, TD also showed a lowered dissolution difference between fed and fasted states in comparison to crystalline APT, indicating a reduction in the positive food effect of APT. Moreover, we assessed the impact of polymer inclusion on permeation under in vitro biomimetic conditions. In comparison with the crystalline APT suspension, both BD and TD demonstrated approximately 3.3 times and 14 times higher steady-state flux (Jss values), respectively. This can be ascribed to the supersaturation and presence of drug-rich submicron particles (nanodroplets) along with the multiple aggregates of drug with phospholipids and polymer in the donor compartment, consequently resulting in a more substantial driving force for passive diffusion. Lastly, in vivo pharmacokinetic evaluation demonstrated the enhanced absorption of both TD and BD over the free drug suspension in the fasted state. This enhancement was evident through a 2.1-fold and 1.3-fold increase in Cmax and a 2.3-fold and 1.4-fold increase in AUC0-t, respectively. Overall, these findings emphasize the potential of polymer-based phospholipid dispersion in enhancing the overall biopharmaceutical performance of APT.

Contributory roles of concentration and pH in CaCO3 growth inhibition for submicron particles synthesis with additive Ca2+

Excessive growth of CaCO3 precipitates is inhibited by additive Ca2+. Here, we report the influence of concentration and solution pH on the extent of growth inhibition. Equal volumes of equimolar CaCl2 and Na2CO3 solutions were mixed and continuously dispersed in Ca(OH)2 solution, where Ca2+ irreversibly adsorb on the precipitates. Compared to conditions where additive Ca2+ are absent, this method can produce more than 90% decrease in particle size. We observe the degree of growth inhibition increases as the concentration of additive Ca2+, relative to the volume of precipitates, increases. An unusual role of pH is also revealed: growth inhibition that leads to the synthesis of monodisperse submicron CaCO3 particles is only observed in high alkaline pH conditions. Additive Ca2+ adsorb on CaCO3 precipitates in pH conditions above the isoelectric point (pH ≈ 9), but their ability to limit CaCO3 growth diminishes when pH < 12.

Effective pickering emulsifiers based on submicron carboxymethyl cellulose/chitosan polymer particles

In this study, cross-linked carboxymethyl cellulose/chitosan submicron particles were employed to facilitate the stabilization of Pickering emulsion. The polymer particles were prepared using the polyelectrolyte self-assembly method in conjunction with isocyanide based multicomponent reactions and the characteristics were obtained using: nuclear magnetic resonance, Fourier-transform infrared spectroscopy and dynamic light scattering. Atomic force microscopy revealed the heterogeneous structure of the resulting submicron particles with domains of 20–30 nm in size. The average diameter was found to be in the range of 229–378 nm and they were found to be suitable for the fabrication of oil/water Pickering emulsion when proceeded via the homogenization method followed by sonication. The results obtained revealed that carboxymethyl cellulose/chitosan particles significantly stabilized the droplets at the oil/water interface. Even at low particle concentrations of 0.3 g/L (which is close to that of low molecular weight surfactants) stable Pickering emulsions have been obtained. Additionally, the resulting emulsions showed a high level of stability with regard to changes in pH, temperature and ionic strength. The natural alkaloid piperine was used as a model compound to load the resulting particles, which possessed encapsulation efficiency of 90.6±0.4%. Furthermore, the in vitro release profile of piperine from the Pickering emulsion revealed a much-controlled release in both acidic and neutral media as compared to the unformulated piperine. Additional findings in this work revealed important information on the application of carboxymethyl cellulose/chitosan submicron particles as Pickering stabilizers for creation of new delivery systems.

Cleaning and Particle Challenges in the Temporary Bonding and Debonding Process

The demands of 5G, Internet of Things and other global technology trends, combined with the increasing cost of scaling down process nodes, have created a shift towards more integrated packaging requirements. The emergence of advanced packaging technologies, such as Fan-Out Wafer Level Packaging (FOWLP), 2.5D/3D IC packaging, and heterogenous integration, brings potential for smaller form factors with increased functionality and bandwidth [1]. Backside processing or thinning of the device wafer is often needed for enabling these technologies. This requires the device wafer be adhered to a rigid carrier wafer using a temporary bonding material (TBM) for mechanical support during handling and processing. Following carrier release, the TBM must be thoroughly removed and cleaned from the device wafer. Many of these adhesives are exposed to high-power lasers or elevated temperatures, making removal more challenging. Sub-micron particle level clean demands for temporary bonding material (TBM) removal are also reaching standards typically reserved for front-end-of-line (FEOL) processing. This is especially crucial in 3D processes such as hybrid bonding where feature and pitch sizes are nearing &lt;1 µm and insufficient cleaning can lead to failures in subsequent bonding processes [2]. Thus, careful consideration of all processing steps is necessary to meet stringent particle demands. This work investigates the removal of coated and baked TBM on silicon wafers, with an emphasis on processing conditions that obtain best particle results. Several chemistries were assessed at the beaker level by performing coupon-level studies and measuring surface properties. Based on these findings, studies with 300-mm wafers were performed using a customizable single-wafer processing tool.

The Effect of Novel Submicronic Solid Activators on Sphalerite Flotability

In this study, we examine the effect of novel submicronic activators made from copper minerals and copper-rich concentrate on sphalerite flotability. The copper minerals and copper concentrate are ground in a vibratory micromill and ultrasonically treated to obtain submicronic sphalerite activators. Histograms show that the concentration of copper particles in the activator after treatment is 92%–94%, with particle sizes of 105–115 nm. The results concerning monomineral flotation showed that sphalerite flotation is possible with the use of submicronic copper particles as an activator. At the same time, the consumption of mineral copper is much lower (by 10 times) than that of copper sulfate. The best results are achieved when submicronic particles of covellite and bornite (with a 60% concentration of particles 300–500 nm in size) were used. Sphalerite recovery amounted to 80%, which is higher than the recovery obtained with the use of copper sulfate by 2% but is 2% lower compared to the use of copper oxyhydroxide. The flotation effect of the submicronic activators on sphalerite was tested in laboratory conditions using polymetallic ore from one of Kazakhstan’s deposits. It is shown that the novel submicron activators based on bornite and copper concentrate exhibit much lower consumption rates and can replace the more expensive copper sulfate at the same Zn content (54.8%–54.9%), obtaining recovery rates of 95.69%–96.57%.

Seasonal charge distributions of submicron atmospheric particles in Yokohama, Japan

Charge distribution measurements are required to understand the spatiotemporal distribution of the number concentrations of submicron atmospheric particles that affect radiative forcing and particle deposition in human airways. The number concentrations of non-charged and charged particles within the 0.3–0.5 μm diameter (D) range were measured at Keio University in Yokohama, Japan, from June 2022 to January 2023 by combining a parallel-pate particle separator and optical particle counters to investigate critical parameters controlling the charging state of submicron atmospheric particles. The measurement uncertainties in the average charge number per particle (pave) and the standard deviation (1σ), derived from the charge distribution of the submicron particles, were within 15%. The monthly median values of 1σ increased in summer and decreased in winter and correlated with the water vapor amount and wind speed. The 1σ values in summer and winter, derived from the seasonally averaged charge distributions of particles, were close to those from the theoretically calculated charge distribution of particles within 0.387–0.5 μm D range and with D = 0.3 μm, respectively, suggesting that the observed particle charge distributions approached the stationary charge distribution for the effective D. In summer, the frequent transport of water molecules and ions from the Pacific Ocean causes efficient collisions between multiple ions and submicron particles with a larger effective D, which may expand the charge distribution of particles. The polarity ratio, the concentration of positively charged particles relative to that of negatively charged particles, was almost unity, indicating the well-balanced charge polarity of the submicron atmospheric particles. The polarity ratio and pave changed significantly during lightning events, indicating that the atmospheric particle charge balance broke. Our findings show that the charge distribution of submicron atmospheric particles can be partly controlled by meteorological parameters (e.g., absolute humidity) and the microphysical properties of the particles.

Micro and Macro Flooding Mechanism and Law of a Gel Particle System in Strong Heterogeneous Reservoirs.

To address the issue of ineffective injection resulting from the consistent channeling of injected water through highly permeable channels in ultra-deep, high-temperature, high-salinity, and strongly heterogeneous reservoirs during the production process, a gel particle profile control agent suitable for high-temperature and high-salinity conditions was chosen. With the help of the glass etching visual microscopic model and the heterogeneous long core model, the formation mechanism of a water flooding channeling path and the distribution law of the remaining oil were explored, the microscopic profile control mechanism of the different parameters was clarified, and the profile control effect of macroscopic core displacement was analyzed. The research shows that the formation mechanism of a water flooding channeling path is dominated by the distribution law of the permeability section and the connection mode between different penetration zones. The remaining oil types after water flooding are mainly contiguous block, parallel throats, and multi-branch clusters. The profile control effect of gel particles on reservoir vertical heterogeneity is better than that of reservoir lateral heterogeneity. It was found that 10 wt% submicron particles with a median diameter of 600 nm play a good role in profiling and plugging pores of 5-20 μm. In addition, 10 wt% micron-sized particles with a median diameter of 2.63 μm mainly play a strong plugging role in the pores of 20-30 μm, and 5 wt% micron-sized particles with a median diameter of 2.63 μm mainly form a weak plugging effect on the pores of 10-20 μm. The overall profile control effect of 10 wt% submicro particles is the best, and changes in concentration parameters have a more significant effect on the profile control effect. In the macroscopic core profile control, enhanced oil recovery (EOR) can reach 16%, and the gel particles show plugging, deformation migration, and re-plugging. The research results provide theoretical guidance for tapping the potential of the remaining oil in strong heterogeneous reservoirs. To date, the gel particles have been applied in the Tahe oilfield and have produced an obvious profile control effect; the oil production has risen to the highest value of 26.4 t/d, and the comprehensive water content has fallen to the lowest percentage of 32.1%.

Improving Fine Particle Removal Using a Single-Channel Slit Bubbling Device in Wet Flue Gas Desulfurization System.

To improve the cleanliness of coal-fired power plants' particulate matter emissions, a novel device (single-channel slit bubbling particle removal device (SCSB-PRD)) is proposed to improve the wet flue gas desulfurization system's (WFGDs) collaborative particle removal effect. Actual coal-fired flue gas was used to test the particle removal performance. The results showed that the flue gas temperature had no obvious effect on the scrubbing effect of the SCSB-PRD. The scrubbing space, scrubbing liquid volume, and flue gas flow rate effectively changed the gas-liquid flow state, and the bubbling state was the key factor in particle removal. The jet-bubbling contact state was more conducive to removing particles than the foam bubbling state. The jet-bubbling state improved the removal efficiency of fine particles by approximately 30% compared to the foam bubbling state. The device operated in a single stage, and the removal performance of the particulate matter reached more than 60%. Even the submicron particles had a satisfactory removal performance of greater than 50%. The particulate matter concentration at the outlet of the WFGDs was reduced to less than 10 mg/m3, which provides a feasible transformation path for ultraultra-low emissions of particulate matter from coal-fired power plants.

Particles in Raw Sheep Milk Can Modulate the Inflammatory Response in THP-1, a Human Monocyte Cell Line, In Vitro

Background: The UK dairy sheep industry is relatively small but growing, particularly for cheese and yogurt products. Anecdotally, sheep milk (SM) may be better tolerated by humans than cows’ milk and could have environmental as well as health benefits. All milk contains sub-micron particles called extracellular vesicles (EVs) which are mainly derived from the mammary epithelium. Physiologically, milk-derived EVs are thought to aid in the development of infant immunity and the microbiome, but may also have health benefits to adult humans. The purpose of this study was to determine whether EVs could be isolated from raw sheep milk and whether they have any effect on inflammatory responses in THP-1, a human monocyte cell line, in vitro. Methods: Using sequential ultracentrifugation, vesicles of &lt;1 µm (LEV) followed by &lt;200 nm (sEVs) were isolated from six individual sheep during mid-lactation. RNA was extracted and microRNA analyzed by RTqPCR for sequences previously identified in cows’ milk. Human THP-1 monocytes were differentiated into macrophages and incubated with SM-derived LEVs and sEVs in the presence of pro-inflammatory LPS to measure the effects on the secretion of the chemokine CCL-2 or in the presence of DMNQ and fluorescent dihydrorhodamine-1,2,3 to measure reactive oxygen species. Results: LEVs induced an increase in ROS in both monocytes and macrophages, whilst sEVs decreased DMNQ-mediated ROS in macrophages but not monocytes. Interestingly, the LEVs did not induce CCL2 release; however, they increased LPS-induced CCL2 secretion in monocytes but not macrophages. miR26a, miR92a, miR125b, miR155 and miR223 were identified in both sEVs and LEVs by RT-qPCR and could be responsible for the modulation of ROS and CCL2 expression. Conclusions: These findings suggest that like cows’ milk, sheep milk contains EVs, and they can influence human monocyte/macrophage responses, and so is worthy of further investigation for its potential human- and non-human-animal health benefits.

Synthesis of High-Precision Sub-Micron CaCO3 Anticancer Drug Carriers from Coral Remains

Calcium carbonate (CaCO3) particles have attracted increasing attention as a promising material for drug delivery systems. In this study, coral remains were utilized as a raw material for a novel drug carrier. A series of pre-treatment and parameter experiments were conducted to synthesize sub-micron spherical CaCO3 particles. The CaCO3 particles exhibited uniform size distribution, with the minimum mean size being only 344 nm. The effects on the CaCO3 crystal phases and particle sizes were also discussed in this study. Drug loading experiments were also conducted to assess the feasibility of the CaCO3 drug carrier. We loaded TRITC-Dextran into CaCO3 particles for the simulation experiments. The loading capacity reached up to 9.6 wt.%, which was as high as common drug carriers such as liposomes. In this study, we aimed not only to tackle the local environmental issues caused by coral remains, but also to synthesize a suitable drug carrier for cancer therapy using the outstanding properties and low cost of CaCO3.

Oligomers are a major fraction of the submicrometre particles released during washing of polyester textiles

Synthetic textiles are a significant source of microplastic fibre pollution. While the microplastic fibre release mechanism during the washing of textiles is well studied, little is known about the release of nanoplastics. The first investigations on the nanoplastic fraction released during the washing and abrasion of polyester textiles have been published; however, questions were raised regarding the chemical composition of the observed submicrometre particles. Using a combination of analytical methods, we show here that 12 different polyester textiles released 4.6 × 1010 to 8.9 × 1011 particles per gram of textile during washing, with a mean size of 122–191 nm. The number of released submicrometre particles was not significantly influenced by the cutting method nor by the textile structure, but positively correlated (P < 0.01) with the number of submicrometre particles present on the fibre surface before washing. We found that 34–89% of the extracted submicrometre particles were soluble in ethanol. These particles are most likely water-insoluble poly(ethylene terephthalate) oligomers. Our results clearly show the urgent need to better understand the contribution of water-insoluble oligomer particles to the pollution of the environment by anthropogenic nanoplastics.