Dispersed Suspensions Research Articles

Investigation of serpentine entrainment reduction in pentlandite flotation using eco-friendly sodium alginate in suspension dispersion systems

Magnesium silicates pose severe environmental issues in hydrometallurgical processes. Copper-nickel sulfide ores are the primary source for nickel production, but their increasingly complex properties make separation difficult, causing slimy magnesium silicate minerals to be entrained into the concentrate with the foam, leading to magnesium contamination. Studies have found that sodium alginate (SA), as an environmentally friendly polymer reagent, can effectively inhibit serpentine. This work investigates the effect of SA on the flotation behavior of pentlandite and serpentine in a sodium hexametaphosphate (SHMP) system. Sedimentation tests show that only a low dosage of SA can effectively settle serpentine, while excessive SA disperses serpentine. Flotation tests indicate that SA can further increase the difference in recovery rates between pentlandite and serpentine based on SHMP. Results from artificial mixed ore tests demonstrate that the recovery rate of serpentine decreases from 51.22% to 37.37% with the addition of SA, with minimal impact on the recovery rate of pentlandite. To explain the impact of the SA adsorption process on the mineral states, the following tests and analyses were conducted: TOC and QCM-D results indicate that SA mainly adsorbs onto serpentine, forming rigid adsorption at low dosages and flexible adsorption at high dosages. Zeta potential tests reveal changes in the surface potential of the minerals, explaining the transition from electrostatic attraction to electrostatic repulsion between pentlandite and serpentine. FTIR and XPS results show that SA chemically reacts with the Mg and Si sites on the serpentine surface through its -COO- groups. In summary, in the SHMP system, the use of gel adsorption and the chemical interaction of SA to coagulate and depress serpentine reduces its entrainment into the concentrate, achieving efficient separation of pentlandite and serpentine. However, high dosages of SA do not yield satisfactory results.

Influence of bivalent ions on the dispersion and gelation of ceramics suspensions

Influence of bivalent ions on the dispersion and gelation of ceramics suspensions

Dissipation and Dietary Risk Assessment of the Fungicide Pyraclostrobin in Apples Using Ultra-High Performance Liquid Chromatography-Mass Spectrometry.

The fungicide pyraclostrobin is the main measure used to control apple alternaria blotch in production. To evaluate the potential dietary risks for consumers, the dissipation and terminal residues of pyraclostrobin were investigated using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS). Pyraclostrobin in apples was extracted by acetonitrile with 2% ammonia and then purified using primary secondary amine (PSA) and graphitized carbon black (GCB). The method showed good linearity within the concentration range of 0.005-0.1 mg L-1, with a coefficient of determination (R2) ≥ 0.9958. The recoveries ranged from 96.0% to 103.8%, with relative standard deviations (RSDs) between 0.8% and 2.3%. The limit of quantification (LOQ) was 0.01 mg kg-1. Pyraclostrobin dispersible oil suspension was applied in 12 apple fields across China according to good agricultural practices (GAPs). In Beijing and Shandong, the dissipation of pyraclostrobin followed first-order kinetic equations, with a half-life of 11 days. The terminal residues ranged from <0.01 to 0.09 mg kg-1. The national estimated daily intake (NEDI) of pyraclostrobin was compared with the acceptable daily intake (ADI), resulting in risk quotient (RQc) of 80.8%. These results suggest that pyraclostrobin poses a low health risk to consumers under GAP conditions and according to recommended dosages.

Sea urchin-like nanocarrier for enhancing pesticide retention and rain fastness on hydrophobic and hydrophilic crop foliage

Foliar washoff by rainfall is a major factor inducing the inefficient utilization of pesticides. Enhancing the adhesion and retention of pesticide on plant foliage has long been of interest. The presence of waxy platelets on most plant foliage surfaces renders them rough and hydrophobic. This reduces the area of contact between pesticide particle and plant foliage, which decreases the adhesion. In this study, we developed a pesticide nanocarrier (PANI/HACC) with sea urchin-like surface morphology based on polyaniline (PANI) doped with biodegradable 2-hydroxypropyltrimethyl ammonium chloride chitosan (HACC). Then, azoxystrobin (AZOX) loaded nanoparticles (AZOX@PANI/HACC) was synthesized by physical adsorption. It exhibited retention rates of 61.4% on rice leaves and 64.6% on cucumber leaves, which were higher than that of commercially available azoxystrobin water dispersible granules (AZOX-WDG, 42.1% and 24.5%, respectively) and suspension concentrates (AZOX-SC, 23.1% and 58.8%, respectively). Additionally, pot experiments demonstrated that the control efficacy of AZOX@PANI/HACC on rice against Rhizoctonia solani was 1.64-fold and 3.0-fold of that of AZOX-WDG and AZOX-SC, respectively. The higher retention performance of AZOX@PANI/HACC was attributed to the stable adhesion by fitting nanometer-sized spikes into the spaces between the waxy platelets. Overall, the pesticide nanocarrier with spiky surface morphology provides an effective strategy for improving pesticide retention and reducing pesticide loss in agricultural production.

Improving Oral Bioavailability of Meloxicam: Development and Characterization of Solid Dispersions

This study investigated the development of a solid dispersion to improve the solubility and dissolution of meloxicam, a poorly water-soluble drug. Meloxicam is used to treat pain and inflammation in various conditions. The challenge was to enhance the drug's oral bioavailability by overcoming its low solubility. Two approaches were explored:&#x0D; &#x0D; 1. Kneading method with Poloxamer 407: This method resulted in a formulation with significantly improved solubility compared to the pure drug.&#x0D; Solvent evaporation method with PVP K-30: While this method offered satisfactory solubility enhancement, it was not as effective as the kneading method with Poloxamer 407.Following the development of the optimized solid dispersion, a suspension formulation was prepared using various suspending agents. The optimized drug formula was then incorporated into the suspension mix. Characterization studies confirmed compatibility between the drug and excipients. FT-IR analysis showed no interaction between the drug and the carriers. Scanning electron microscopy (SEM) revealed a change in meloxicam particle morphology from crystalline to a more amorphous form, indicating a reduction in particle size and a potential explanation for the improved dissolution profile. The dissolution profile of the solid dispersion suspension prepared by the kneading method with Poloxamer 407 outperformed the one prepared with the solvent evaporation method and PVP K-30.This study demonstrates the effectiveness of the kneading method with Poloxamer 407 in developing a solid dispersion of meloxicam with enhanced solubility and dissolution. The optimized formulation exhibited good stability, acceptable drug content and release, and satisfactory rheological properties. This approach has the potential to improve the bioavailability of meloxicam and lead to a more effective oral dosage form.&#x0D; &#x0D; Keywords: Oral Bioavailability, Meloxicam:, Solid Dispersions , FT-IR analysis, SEM

Synergy of Al2O3/GO hybrid nanofluids: Molecular dynamics perspective on dispersion/adsorption evolution and its tribological validation

A synergistic Al2O3/GO hybrid nanofluid was developed, aiming to attain prominent tribological properties for application in mechanical engineering. On the support of a molecular dynamics approach, amorphous models were simulated, thus illustrating the agglomeration or the adsorption in nanofluids, as well as revealing the evolution of the laminated adsorbed structure. Further, single-component or hybrid nanofluids were characterized and their tribological validations were performed. The results showed that the modified nanofluids realized dispersion equilibrium and suspension stabilization at the molecular level, and their wettability or thermo-physical indexes were improved, which was beneficial for the tribological performance. Especially in hybrid nanofluids, the synergistic effect further enhanced these capabilities, thereby maintaining a small friction coefficient and a flat wear region.

Tracking colloidal silica particles to evaluate their dispersion and interactions in concentrated suspensions under shear force applications.

This study aimed to characterize interactions within colloidal silica particles in their concentrated suspensions, using rheo-confocal measurements and imaging, followed by image analysis. We studied the effect of shear rate (0-500s-1) and solution pH (6, 10) on the dispersion degree of colloidal silica particles via the determination and comparison of interparticle distances and their modeling. Images corresponding to different shear rates were analyzed to identify the coordinates of the particles. These coordinates were further analyzed to calculate the distance among the particles and then their surface-to-surface distance normalized by the particle diameter (H/D). It was found that the population of the particles per unit area of the image and H/D varied with increasing shear rate. The comparison between experimentally measured and theoretically calculated H/D identified that for some particles, the former was shorter than the latter, indicating the unexpected attractions among them against the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Then, the modification of previously reported equations for H/D was suggested and confirmed its validity. Assuming pair potential interaction and hydrodynamic interaction were the main non-DLVO interactions, their magnitudes were calculated and confirmed the significance of pH and shear application strength on particle dispersion/coagulation.

Ice nucleation in the presence of nucleation promoters dispersed in tetrabutylammonium bromide (TBAB) solutions

Ice nucleation is the initial step of ice formation that has significant impact on global climate, several engineering and structural surfaces and other systems like clathrate hydrates. The nucleation promoters for ice have been studied for decades but some problems or mechanisms remain unclear. In our earlier study [1], Snomax was found to be the most effective promoter among the common ice nucleation promoters we had tested and it was postulated that the efficacy of Snomax might be aided by its larger interfacial area available for heterogeneous nucleation because it could be easily dispersed in water. Here we attempted to disperse the three ice nucleation promoters which we had previously found to be effective – AgI, kaolinite and cholesterol – into liquid water to increase the interfacial area with water and the heterogeneous nucleation rate of ice. We found dispersion of these promoters into water to be difficult and required addition of Tetrabutylammonium bromide (TBAB) to the aqueous phase before they could be dispersed. We then investigated the nucleation rates of ice in the dispersed nucleation promoter suspensions. We found (1) addition of TBAB alone unexpectedly promoted the nucleation of ice, (2) dispersing AgI into 1 mM TBAB solutions further promoted ice nucleation, (3) dispersing kaolinite or cholesterol in TBAB solutions did not promote ice nucleation more so than the TBAB solutions without kaolinite or cholesterol.

A new algorithmic approach for predicting the particle size distribution of dispersed soil suspensions using an automated optical settling column

Analyzing a large number of samples for their dispersive properties and particle size distribution (PSD) is often cumbersome and time-consuming, particularly when using traditional hydrometer or pipette-based methods. In this study, we analyzed the efficacy and rapidity of an automated, optical settling column (OSC) to measure the PSD of soils. The OSC provided backscattering and transmission intensity profiles at preprogrammed time intervals that illustrated sedimentation/flocculation processes of suspended particles, making the approach desirable for soil dispersion studies. Settling experiments were performed using 177 soil samples collected from 59 sampling locations across the United States. All soil samples were pretreated with sodium hexametaphosphate (HMP) to achieve maximum dispersion and analyzed with the OSC. The effects of settling run time and sampling frequency were also investigated. The results were compared with separate soil PSD data obtained using the common particle sizing analysis, the pipette method. Using feature engineering and dimensionality reduction, we created different novel methods of modeling the PSD data. Resampling was employed to compare accuracy of these novel methods by generating 300 instances of model performance for each method. We further estimated model generalization using two techniques: (i) a holdout (HO) estimation approach to suggest the “best-case” performance and (ii) an averaged model performance to provide a more conservative performance estimate. The best method studied here provided PSD values that deviated from those gathered through the pipette method by between 2.8% − 3.3% for clay, 5.7% − 9.4% for silt, and 6.5% − 9.6% for sand.

Theoretical investigation of solvation and inter-chain interactions for phosphate ester dispersants on tetragonal BaTiO3 (0 0 1) in non-aqueous solvents: An ab initio molecular dynamics simulation approach

Tetragonal BaTiO3 is a key material for manufacturing multi-layer ceramic capacitors (MLCCs), and a highly dispersed BaTiO3 suspension, where the surfaces are conjugated by phosphate ester dispersants, is an essential technology for the production of ultra-thin films and small-sized ceramic capacitors. Therefore, understanding the interactions of conjugated polymers with solvents is critical to designing improved dispersants and solvents for commercial MLCC applications. In this work, we theoretically investigate the solvation and inter-chain interactions of mono-alkyl and ethoxy phosphate esters under methanol, ethanol, isopropanol, 1-butanol, and toluene, on tetragonal BaTiO3 (001) using the ab initio molecular dynamics (AIMD) simulations. Our results show that the total number of solvent molecules surrounding mono-alkyl and ethoxy phosphate esters decreases in the order of methanol > ethanol > isopropanol > 1-butanol > toluene, indicating that solvation via van der Waals forces and hydrogen bonding declines with increasing the hydrophobicity of solvent molecules. Also, the solvation interaction energy has a linear correlation with the experimental differential of zeta potential, suggesting that the calculated energy is associated with electrostatic environment at the dispersant/solvent/BaTiO3 interface. Therefore, the solvation interaction energy is an important factor that describes the liquid–solid interfaces as well as a dispersion stability of BaTiO3 suspension.

Comparison of cellulose nanocrystal dispersion in aqueous suspension via new and established analytical techniques

Comparison of cellulose nanocrystal dispersion in aqueous suspension via new and established analytical techniques

Eco-friendly cellulosic photonic pigments with tunable structural color for anti-counterfeiting and decorative applications

Cholesteric cellulose films exhibiting an adjustable reflection wavelength across the entire visible range were obtained through the application of ultrasound treatment to a suspension of cellulose nanocrystals (CNCs) prior to casting. The influence of both low and high intensity ultrasound power on the structural color of iridescent films was systematically investigated, along with an elucidation of the mechanism behind helical pitch regulation. The findings reveal that low ultrasonic power applied to the CNC suspension has minimal impact on the structural color of the CNC film, primarily enhancing the dispersion of CNC. On the other hand, high ultrasonic power applied to the CNC suspension can effectively adjust the structural color thanks to not only improving the dispersion of CNCs suspensions, but also altering the morphology and size of the CNCs. More importantly, co-friendly cellulosic photonic pigments with tunable structural color can be easily obtained utilizing the fragility of iridescent films for applications such as anti-counterfeiting labels, nail modification and decorative coatings and so on, thereby demonstrating considerable potential for practical utilization.

Resource utilization of polystyrene waste by preparation of high performance dispersant for coal‒water slurry

ABSTRACT In present paper, structures and properties of degradation products of polystyrene (PS) waste were characterized by gel permeation chromatography (GPC), thermogravimetric (TG) analysis, Fourier transform infrared (FT-IR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), and thus the degradation conditions including temperature, time, and assistant type and dosage were investigated and optimized. It is suitable to use 1.0 wt% K2S2O8 as an assistant to degrade PS waste at 300°C for 24 h. Subsequently by sulfonation and neutralization reactions, the degraded PS was prepared into sodium polystyrene sulfonate (PSS), a common dispersant for coal‒water slurry (CWS). The performance of PSS with different molecular weights and sulfonation degrees was studied. Experimental results showed that the PSS with the sulfonation degree of more than 75%, prepared from the degraded PS having number average molecular weight (M n) of about 9000, was appropriate for dispersion and stabilization of CWS suspensions. Additionally, compared with commercial dispersant NSF, the obtained PSS had a better performance for CWS. CWSs prepared with dispersant PSS exhibited pseudo-plastic or shear-thinning rheological behaviors. Combined with coal‒water slurry technology, a new approach is provided for resource utilization of PS waste.

Study of analgesic and myotropic spasmolytic activity of alkylcarb

The work is devoted to the search for new biologically active substances in a series of alkylamides of dihydroquinoline-3-carboxylic acid. Analgesic properties of 30 newly synthesized substances were studied, which made it possible to identify the leader compound (provisional name alkylcarb) and recommend its effectiveness for further research as an antispasmodic agent for pain relief. It has been established experimentally, that the substance alkylcarb exhibits concentration-dependent vasodilatory properties in vitro on segments of the thoracic aorta of rats. The data, obtained in the work, justify the prospect of using the leader substance as a new analgesic and antispasmodic drug. The research expands and deepens knowledge about the pharmacological properties of alkylamide derivatives of dihydroquinoline-3-carboxylic acid.&#x0D; The aim of the work was to conduct screening studies to establish the analgesic activity of a newly synthesized series of chemical compounds among alkylamides of dihydroquinoline-3-carboxylic acid and to study the myotropic spasmolytic activity of the leader substance.&#x0D; Materials and methods. Analgesic properties of alkylamides of dihydroquinoline-3-carboxylic acid were studied on outbred white mice in the "acetic acid convulsions" test. During the experiment, the animals were treated in accordance with the International Principles of the European Convention for the Protection of Vertebrate Animals Used for Experiments and Other Scientific Purposes (Strasbourg, March 18, 1986). The studied substances were administered intragastrically to experimental animals at a dose of 10 mg/kg in the form of a finely dispersed aqueous suspension, stabilized with Tween-80. Voltaren at a dose of 8 mg/kg, recommended for preclinical studies, and analgin at a dose of 50 mg/kg were chosen as reference drugs.&#x0D; The studies of the contractile activity of smooth muscle vessels were carried out on segments of the thoracic aorta of rats of both sexes weighing 180-200 g. The studies of dilator reactions were carried out against the background of preliminary contraction with phenylephrine at a concentration of 10-6 mol/l. The antispasmodic efficiency of the new compound was determined in comparison with the classic antispasmodic drotaverine.&#x0D; The statistical processing of the results was carried out using the package of statistical analysis of electronic spreadsheets Exel, with the help of the program "Statgraphics Plus v. 3.0.” and the standard package of statistical programs "Statistica, V. 6.0". We used the Student's test, a non-parametric analog of univariate variance analysis - the Kruskal-Wallis test, and the Mann-Whitney test. Differences were considered statistically significant at p&lt;0.05.&#x0D; Results. The study of the analgesic activity of substances АO1-АO30 in the "acetic acid convulsion" test in mice showed that a compound АO26 (provisional name alkylcarb) has the most pronounced analgesic activity when administered intragastrically. In the "acetic acid convulsion" test, alkylcarb (10 mg/kg, per os) probably reduces the number of convulsions, caused by acetic acid. The level of activity of this compound is comparable to the activity of diclofenac (8 mg/kg, per os) and exceeds analgin (50 mg/kg, per os). The substance alkylcarb relieved vasospasm at the level of the comparison drug drotaverine in in vitro experiments on a model of an isolated fragment of the thoracic aorta of rats against the background of previous constriction with phenylephrine.&#x0D; Conclusion. Today, the search for new highly effective non-opioid analgesics is an urgent problem of modern pharmacology, since painkillers used in clinical practice do not meet the requirements of efficiency and safety. In this regard, in recent years, scientists of the National Pharmaceutical University have been intensively searching for new, highly effective substances with antinociceptive, anti-inflammatory and antipyretic effects among alkylamides of dihydroquinoline-3-carboxylic acid.

Coastal Depositional Responses to Relative Sea-Level Rise: Insights from a Superimposed Sandstone–Shale–Coal Reservoir in the Linxing Gas Field, China

The Ximing Sandstone-to-No. 9 Coal succession of the Taiyuan Formation in the Linxing gas field records a complex internal architecture of a transgressive succession developed in the western coast of the late Pennsylvanian North China epeiric sea. Facies and sequence stratigraphic analyses reveal its depositional evolution from fluvial channels through fluvial-dominated and tide-influenced inner estuaries to tide-dominated estuaries and finally to wave-dominated barrier lagoons. The evolution from fluvial- to tide-dominated deposition has been ascribed to the funnel-shaped valley coupled with an increased tidal prism induced by the upstepping and backstepping shoreline. The evolution from tide- to wave-dominated deposition has been ascribed to the wide North China epeiric seaway lacking local coastline irregularities after the incised-valley fill that provided sufficient fetch for the occurrence of large storm waves. Grain-size analysis reveals the relative importance of traction, saltation, dispersed suspension, and flocculated suspension in the development of the transgressive estuarine to lagoonal deposits. This study not only contributes to a proper understanding of coastal depositional response to the relative sea-level rise but also provides a context within which to interpret the symbiotic relationship of the superimposed sandstone–shale–coal reservoirs and predict the distribution of favorable unconventional gas production formation.

Dispersion of a gyrotactic micro-organism suspension in a vertical pipe: the buoyancy–flow coupling effect

Understanding the transport of micro-organisms in pipes is crucial to many fundamental problems, such as bioconvection and biodiesel production. In this work, we investigate the velocity profile and dispersion of a suspension of negatively buoyant, gyrotactic micro-organisms in a vertical pipe. With an imposed flow rate, the non-uniform radial cell concentration typical of gyrotaxis distorts the simple Poiseuille flow through inhomogeneous buoyancy, which in turn affects the cell concentration distribution. By solving the fundamental Smoluchowski equation and the Navier–Stokes equation simultaneously, we account for this bidirectional buoyancy–flow coupling effect. Asymptotic dispersion coefficients, namely, drift velocity and dispersivity, are further calculated with the obtained radial velocity and cell concentration profiles, which are assumed to be steady, symmetric and axially invariant. Using the gyrotactic micro-organism Chlamydomonas augustae as an example, detailed results are given to illustrate the effect of buoyancy–flow coupling. In downwelling flows, the buoyancy–flow coupling effect intensifies with the Richardson number $Ri$ quantifying the mean cell concentration, but is strongest at a moderate flow strength. The buoyancy–flow coupling effect significantly enhances the velocity and cell concentration in the central region, as well as the drift velocity and dispersivity. In contrast, the buoyancy–flow coupling effect is comparatively limited in upwelling flows, due to the dominant influence of the no-slip boundary condition imposed at the wall. Comparisons with predictions of existing approximate models are also presented.

Analysis of the Adsorbed Vaccine Formulations Using Water Proton Nuclear Magnetic Resonance-Comparison with Optical Analytics.

To evaluate wNMR, an emerging noninvasive analytical technology, for characterizing aluminum-adjuvanted vaccine formulations. wNMR stands for water proton nuclear magnetic resonance. In this work, wNMR and optical techniques (laser diffraction and laser scattering) were used to characterize vaccine formulations containing different antigen loads adsorbed onto AlPO4 adjuvant microparticles, including the fully dispersed state and the sedimentation process. All wNMR measurements were done noninvasively on sealed vials containing the adsorbed vaccine suspensions, while the optical techniques require transferring the adsorbed vaccine suspensions out of the original vial into specialized cuvette/tube for analysis. For analyzing fully dispersed suspensions, optical techniques also require sample dilution. wNMR outperformed laser diffraction in differentiating high- and low-dose formulations of the same vaccine, while wNMR and laser scattering achieved comparable results on vaccine sedimentation kinetics and the compactness of fully settled vaccines. wNMR could be used to analyze aluminum-adjuvanted formulations and to differentiate between formulations containing different antigen loads adsorbed onto aluminum adjuvant microparticles. The resultsdemonstrate the capability of wNMR to characterize antigen-adjuvant complexes and to noninvasively inspect finished vaccine products.

Comparative Assessment of Retention Capacity of Double-Layer Baffle Plates

To dehydrate technical suspensions, diverse in composition, the filter baffle plates made from synthetic fibres (nylon, polyethylene terephthalate (lavsan), tetrafluorethylene (tephlon), ftorlon) are used. High retention capacity of the filter baffle plates on the dispersion phase of the suspension is one of the major requirements. The article represents the assessment of the filter properties the double-layer baffle plates have: cotton, consisted of filter diagonal art. 2074 (substrate) and coarse calico (base), and synthetic nylon, consisted of the fabric art. 56027 (substrate) and the fabric 56159 (base). The kinetics of the filtration process of the different in composition dispersion suspension particles of the red mud has been studied. The formation conditions of the initial filter layer have been described.

The performances and mechanisms for Cr(VI) and Cr(III) removal using TMAOH delaminated Ti3C2Tx suspension

Ultra-thin MXene nanosheets (Nss) were facilely prepared via delaminating and intercalating the multi-layered MXene using tetramethylammonium hydroxide (TMAOH). Electron-rich characteristics, abundant surface active sites and the negative charges made MXene Nss having both good reduction ability and adsorption capacities, which would effectively remove anion Cr(VI) via reduction and remove cation Cr(III) via adsorption. Batch adsorption tests were carried out to study the pH impact, adsorption kinetics and isotherms. Upon adsorption, the well dispersed MXene Nss suspension was aggregated to form flocs and sediment at the bottom. The maximum Cr(VI) and Cr(III) removing capacities are calculated to be 554.9 mg/g at 318 K and 283 mg/g at 298 K, respectively. The mechanisms on Cr(VI)/Cr(III) adsorption were well studied employing SEM, TEM, XPS and FT-IR. In addition, the MXene Nss also showed good adsorption capacity towards other metal cations (such as Cu2+, Cd2+, and Pb2+), manifesting that the current MXene Nss has the potential to be used as a general-purpose adsorbent.

Bioactivity, Uptake, and Distribution of Prothioconazole Loaded on Fluorescent Double-Hollow Shelled Mesoporous Silica in Soybean Plants.

Prothioconazole (PTC) has been widely utilized for plant fungal disease control, but its metabolite prothioconazole-desthio (PTC-d) exhibits reproductive toxicity. In the present study, carbon quantum dot (CQD)-modified fluorescent double-hollow shelled mesoporous silica nanoparticles (FL-MSNs) loaded with PTC, referred to as PTC@FL-MSNs, were constructed with an average size of 369 nm and a loading capacity of 28.1 wt %, which could increase the antifungal efficiency of PTC. In addition, upright fluorescence microscope and UPLC-MS/MS studies showed that PTC@FL-MSNs could be effectively transported via root uptake and foliar spray in soybean plants. Compared to a 30% PTC dispersible oil suspension agent, the PTC@FL-MSN treatment group showed higher concentrations (leaves: 0.50 > 0.48 mg/kg), longer half-lives for degradation (leaves: 3.62 > 3.21 d; roots: 3.39 > 2.82 d), and fewer metabolites. These findings suggest that sustained pesticide release and toxicity reduction are potential applications for PTC nanofungicide delivery technology.