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In an attempt to expand the utility of natural compounds in catalysis, a novel heterogeneous catalyst derived from Gum Arabic, a natural polysaccharide, was synthesized by its modification with chlorosulfuric acid and subsequent magnetization. Material characterization confirmed the successful modification and magnetization of GA. Hammet method also approved increase of acidity of gum upon functionalization with chlorosulfuric acid. According to Response Surface Methodology optimization, this catalyst exhibited high activity for the conversion of fructose to 5-hydroxymethylfurfural under mild conditions, achieving a 96% yield at 85 °C within 73 min using 30 wt% catalyst loading. The kinetic study indicated an activation energy of 89 kJ/mol. Thermodynamic parameters were determined, with enthalpy, entropy, and Gibbs free energy values of 86.11 kJ/mol, − 29.45 J/mol, and 96.65 kJ/mol, respectively. Furthermore, the catalyst displayed excellent recyclability, retaining over 87% activity for five consecutive cycles, and a heterogenous nature as confirmed by hot filtration test. This study demonstrates the potential of the as-prepared catalyst for sustainable 5-hydroxymethylfurfural production, highlighting its high activity, recyclability, and environmentally friendly nature. [ABSTRACT FROM AUTHOR]

In order to reveal adsorption-regulation micromechanism and debonding micromechanism between wall surface and magnetorheological (MR) wall-climbing robot legs, an interparticle normal magnetic attraction (NMA) mechanics model was constructed based upon the magnetic-dipole theory. According to analysis of NMA mechanics, it was confirmed that the interparticle NMA could be intensified with enhancing magnetic-particle diameter but was weakened with ratio of adjacent magnetic-particles distance to magnetic-particle radius. It means that the adhesive capacity between MR wall-climbing robot legs and wall surface could be strengthened by increasing magnetic-particle size and decreasing interparticle distance. Furthermore, it was found that the NMA of the first particle in the magnetic chain was positively related to magnetic-particles number until the magnetic-particles number reached a critical value. Consequently, the adsorption ability between MR wall-climbing robot legs and wall surface could be effectively controlled by changing magnetic-particles number. Besides, the strongest NMA appeared at the middle of the magnetic chain. However, the weakest NMA locates at both ends of the magnetic chain. Thus, it could be concluded that the end of the magnetic chain would be separated from wall surface rather than fracture occurred in the middle of the magnetic chain when the MR wall-climbing robot legs divorced from wall surface. [ABSTRACT FROM AUTHOR]

Abstract In order to reveal adsorption-regulation micromechanism and debonding micromechanism between wall surface and magnetorheological (MR) wall-climbing robot legs, an interparticle normal magnetic attraction (NMA) mechanics model was constructed based upon the magnetic-dipole theory. According to analysis of NMA mechanics, it was confirmed that the interparticle NMA could be intensified with enhancing magnetic-particle diameter but was weakened with ratio of adjacent magnetic-particles distance to magnetic-particle radius. It means that the adhesive capacity between MR wall-climbing robot legs and wall surface could be strengthened by increasing magnetic-particle size and decreasing interparticle distance. Furthermore, it was found that the NMA of the first particle in the magnetic chain was positively related to magnetic-particles number until the magnetic-particles number reached a critical value. Consequently, the adsorption ability between MR wall-climbing robot legs and wall surface could be effectively controlled by changing magnetic-particles number. Besides, the strongest NMA appeared at the middle of the magnetic chain. However, the weakest NMA locates at both ends of the magnetic chain. Thus, it could be concluded that the end of the magnetic chain would be separated from wall surface rather than fracture occurred in the middle of the magnetic chain when the MR wall-climbing robot legs divorced from wall surface.

Abstract Organophosphates (OPs) and carbamates (CMs) play a vital role in Thai agriculture, public health, and pest control. However, their detection presents challenges due to expensive methods requiring specialized expertise. Addressing this gap, our study introduces an innovative, cost-effective method for detecting OPs and CMs in Thailand. We utilized the test kit by using magnetic particles coated with esterase enzymes from honey bee heads combined with a colorimetric approach. The developed test kit shows low limits of detection (LODs) at 0.001 mg/L of dichlorvos (OPs) and 0.004 mg/L for carbaryl (CMs). The efficiency of the developed test kits in comparison with the standard technique of gas chromatography with flame photometry detection (GC-FPD) shows a comparable result in fruit and vegetable residue analysis. This developed test kit proposes a cost-effective OPs and CMs analysis test kit for Thailand, promising expense reduction and simplified verification processes. Its applicability to fruits and vegetables signifies practicality in agriculture, marking a significant advancement in accessible and efficient pesticide residue monitoring. Despite challenges in pesticide use, our method holds promise for improving safety and efficiency in Thai pesticide management. Graphical Abstract

Organophosphates (OPs) and carbamates (CMs) play a vital role in Thai agriculture, public health, and pest control. However, their detection presents challenges due to expensive methods requiring specialized expertise. Addressing this gap, our study introduces an innovative, cost-effective method for detecting OPs and CMs in Thailand. We utilized the test kit by using magnetic particles coated with esterase enzymes from honey bee heads combined with a colorimetric approach. The developed test kit shows low limits of detection (LODs) at 0.001 mg/L of dichlorvos (OPs) and 0.004 mg/L for carbaryl (CMs). The efficiency of the developed test kits in comparison with the standard technique of gas chromatography with flame photometry detection (GC-FPD) shows a comparable result in fruit and vegetable residue analysis. This developed test kit proposes a cost-effective OPs and CMs analysis test kit for Thailand, promising expense reduction and simplified verification processes. Its applicability to fruits and vegetables signifies practicality in agriculture, marking a significant advancement in accessible and efficient pesticide residue monitoring. Despite challenges in pesticide use, our method holds promise for improving safety and efficiency in Thai pesticide management. [ABSTRACT FROM AUTHOR]

This study presents the initial attempt at introducing a magnetic molecularly imprinted polymer (MIP) designed specifically for lamotrigine with the purpose of functioning as a drug carrier. First, the composition of the magnetic polymer underwent optimization based on bulk polymer adsorption studies and theoretical analyses. The magnetic MIP was synthesized from itaconic acid and ethylene glycol dimethacrylate exhibiting a drug loading capacity of 3.4 ± 0.9 μg g−1. Structural characterization was performed using powder X-ray diffraction analysis, vibrating sample magnetometry, and Fourier transform infrared spectroscopy. The resulting MIP demonstrated controlled drug released characteristics without a burst effect in the phospahe buffer saline at pH 5 and 8. These findings hold promise for the potential nasal administration of lamotrigine in future applications. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An overexpression of sialic acid is an indicator of metastatic cancer, and selective detection of sialic acid shows potential for cancer diagnosis. Boronic acid is a promising candidate for this purpose because of its ability to specifically bind to sialic acid under acidic conditions. Notably, the binding strength can be easily modulated by adjusting the pH, which allows for a simple dissociation of the bound sialic acid. In this study, we developed 5-boronopicolinic acid (5-BPA)-modified magnetic particles (BMPs) to selectively capture sialic acid biomolecules. We successfully captured fetuin, a well-known sialoglycoprotein, on BMPs at >104 molecules/particle using an acetate buffer (pH 5.0). Facile dissociation then occurred when the system was changed to a pH 7.6 phosphate buffer. This capture-and-release process could be repeated at least five times. Moreover, this system could enrich fetuin by more than 20 times. In summary, BMPs are functional particles for facile purification and concentration through the selective capture of sialic acid proteins and can improve detection sensitivity compared with conventional methods. This technology shows potential for the detection of sialic acid overexpression by biological particles. [ABSTRACT FROM AUTHOR]

This study proposed a tung-oil based magnetic targeted delivery microcapsules (MDTMs) to enhance the efficiency of self-healing coatings (SHC). Magnetic particles were used as function particles and emulsifier in synthesis of microcapsules (MC). DSC, OM, SEM, TEM, VSM, NSS, EIS and SKP were used to characterize the compounds, structure, healing behavior and anti-corrosion performance. Results indicate that magnetically driven SHC (MD-SHC) reduces 50% migration path of the released tung oil, and increases the release rate of tung oil after the coating is mechanically damaged. SKP and EIS results suggest that the healing part has impressive anti-corrosion performance, scratches were filled with a large amount of tung oil in a short time, and the released tung oil had formed a complete oil film on scratches at 24 h with higher polarization resistance (Rp). Rp of MD-SHC (2.5 × 105–3.6 × 105 Ω cm2) is 2.0–2.8 times of that the SHC (1.1 × 105–1.8 × 105 Ω cm2). The enrichment in MD-SHC at the interface decreases bonding strength from 7 to 4.5 MPa as the mass additive of microcapsules reaches 15 wt.%. The current work proves the effectiveness of MD-SHC in improving self-healing ability.

To meet the increasingly serious challenges of electromagnetic pollution and fire hazards, highly efficient electromagnetic absorbing materials with good flame retardancy have been accurately developed. A complex high-performance electromagnetic absorber was designed by doping graphene oxide heterostructures (including zero-dimensional nanoparticles and two-dimensional graphene) containing cobalt, nickel and iron oxyhydroxide through the coordination effect. When 20 wt% CNFO@rGO was incorporated into paraffin, the minimum reflection loss (RL) reached -51.6 dB at a thickness of 3.5 mm, showing a high electromagnetic absorption efficiency. It was concluded that the excellent impedance matching, the best dielectric loss and the higher magnetic loss caused by the heterostructure combined with the electromagnetic parameters, Cole-Cole semicircle, impedance matching (Z) and attenuation coefficient resulted in excellent electromagnetic wave absorption performance. Moreover, the peak heat release (PHRR) and heat release rate (HRC) decreased by 55.5% and 55.1%, respectively, when 10 wt% CNFO@rGO was incorporated into the epoxy resin (EP), indicating enormous potential for the enhancement of flame-retarding electromagnetic absorbing materials. [ABSTRACT FROM AUTHOR]

Gonorrhea is the second most common sexually transmitted infection (STI) with around 87 million cases worldwide estimated in 2016 by the World Health Organization. With over half of the cases being asymptomatic, potential life-threatening complications and increasing numbers of drug-resistant strains, routine monitoring of prevalence and incidence of infections are key preventive measures. Whilst gold standard qPCR tests have excellent accuracy, they are neither affordable nor accessible in low-resource settings. In this study, we developed a lab-on-a-chip platform based on microscale immiscible filtration to extract, concentrate and purify Neisseria gonorrhoeae DNA with an integrated detection assay based on colorimetric isothermal amplification. The platform was capable of detecting as low as 500 copies/mL from spiked synthetic urine and showed no cross-reactivity when challenged with DNAs from other common STIs. The credit card–size device allows DNA extraction and purification without power or centrifuges, and the detection reaction only needs a low-tech block heater, providing a straightforward and visual positive/negative result within 1 h. These advantages offer great potential for accurate, affordable and accessible monitoring of gonorrhea infection in resource-poor settings. [ABSTRACT FROM AUTHOR]

This study presents the initial attempt at introducing a magnetic molecularly imprinted polymer (MIP) designed specifically for lamotrigine with the purpose of functioning as a drug carrier. First, the composition of the magnetic polymer underwent optimization based on bulk polymer adsorption studies and theoretical analyses. The magnetic MIP was synthesized from itaconic acid and ethylene glycol dimethacrylate exhibiting a drug loading capacity of 3.4 ± 0.9 μg g−1. Structural characterization was performed using powder X-ray diffraction analysis, vibrating sample magnetometry, and Fourier transform infrared spectroscopy. The resulting MIP demonstrated controlled drug released characteristics without a burst effect in the phospahe buffer saline at pH 5 and 8. These findings hold promise for the potential nasal administration of lamotrigine in future applications.

This study proposes a novel process called peeling of nano-particle (PNP) to remove material locally on a hard material surface, such as silicon carbide (SiC), diamond, and gallium nitride (GaN), using the magnetic nano-particles in an aqueous solution controlled by magnetic fields. By the concept of the PNP process, magnetic fields are generated by two solenoid coils, which are sandwiched between the hard material sample, to pull the magnetic nano-particles to adhere to and then peel the material from the sample surface. In this experiment, iron (II, III) oxide (Fe3O4) particles with a diameter size in the range of 50–100 nm were dispersed in water, and the pH value was adjusted to 10 by potassium hydroxide (KOH). The particles were magnetically controlled on the silicon carbide (4H-SiC) surface by the magnetic fields at approximately 17 mT. To confirm the contact phenomenon of the Fe3O4 particles on the 4H-SiC surface during the PNP process, an optical system was developed by applying evanescent field microscopy to limit the observation range to approximately 300 nm from the 4H-SiC surface. According to the experimental observed results, the control phenomenon of two examples of Fe3O4 particles could be observed through their scattering light, which relates to the magnetic field generating sequence wherein the particles were magnetically pulled in and out of the 4H-SiC surface in the limit range of the evanescent field. During the particle pull to the surface, particles were able to be tracked in the X–Y directions during the approach to the 4H-SiC surface. The Brownian motion ranges in all directions of the particles decreased when the particles approached close to the surface due to the pulling magnetic field. Moreover, the magnetic field enforced the magnetic moment of the particle and limited their rotation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co and ZnO particles were anchored to a wrinkle-like multilayer biomass-derived carbon sheets derived from the shaddock peel. • The excellent MA property can be attributed to synergistic effect of wrinkle-like multilayer structures and Co/ZnO particles. • CoZnO/C-X exhibits excellent RL (-54.90 dB)and broad EAB (7.2 GHz) at 10.8–18.0 GHz with matching thickness below 2.0 mm. Biomass-carbon materials have excellent electromagnetic wave attenuation properties, which is one of the essential factors for developing ultra-thin matched-thickness, and high-performance microwave absorption materials. This study reports a two-step procedure consisting of carbonization and subsequent in-situ growth for preparing a wrinkle-like multilayer biomass-derived composites with magnetic Co particles and ZnO particles (CoZnO/C-X). The synergistic effect of a wrinkle-like multilayer structure and Co and ZnO particles, as well as the existence of many heterogeneous interfaces in the composites structure, and efficiently creates multiple scattering and reflections, which gives the composites the strong microwave absorption properties. The minimum reflection loss value (RL min) of CoZnO/C-X reaches − 54.90 dB with a thickness of 1.8 mm, and the effective absorption bandwidth (lower than − 10 dB) is 7.2 GHz covering from 10.8 GHz to18.0 GHz with matching thickness of 2.0 mm. Furthermore, the reasonable dielectric/magnetic losses, optimized impedance matching and enhanced polarization loss play an indispensable role among improving microwave absorption performance. Thus, this result provides a good potential method for preparation of magnetic particle/metal oxide/biomass-derived carbon microwave absorbing structural materials. [ABSTRACT FROM AUTHOR]

Abstract Exfoliation syndrome presents as an accumulation of insoluble fibrillar aggregates that commonly correlates with age and causes ocular complications, most notably open-angle glaucoma. Despite advances in understanding the pathogenesis and risk factors associated with exfoliation syndrome, there has been no significant progress in curative pharmacotherapy of this disease. It is thought that the ability to target the fibrillar aggregates associated with exfoliation may offer a new therapeutic approach, facilitating their direct removal from affected tissues. Phage display techniques yielded two peptides (LPSYNLHPHVPP, IPLLNPGSMQLS) that could differentiate between exfoliative and non-affected regions of the human lens capsule. These peptides were conjugated to magnetic particles using click chemistry to investigate their ability in targeting and removing exfoliation materials from the anterior human lens capsule. The behavior of the fibrillar materials upon binding to these magnetic particles was assessed using magnetic pins and rotating magnetic fields of various strengths. Ex vivo studies showed that the magnetic particle-peptide conjugates could generate enough mechanical force to remove large aggregates of exfoliation materials from the lens capsule when exposed to a low-frequency rotating magnetic field (5000 G, 20 Hz). Biocompatibility of targeting peptides with and without conjugated magnetic particles was confirmed using MTT cell toxicity assay, live/dead cell viability assay, and DNA fragmentation studies on primary cultured human trabecular meshwork cells. This is a novel, minimally invasive, therapeutic approach for the treatment of exfoliation glaucoma via the targeting and removal of exfoliation materials that could be applied to all tissues within the anterior segment of the eye.

Featured Application: Magnetic nanoparticles can be used in a wide range of applications with the aid of an external magnetic field, such as the recycling of magnetic adsorbents, the targeted delivery of drugs, and the targeted migration of lubricant particles. If the motion of magnetic particles in fluids under the influence of magnetic fields can be accurately calculated, this will help to increase the efficiency of particle utilization and broaden particles' application areas. The present calculation starts with a model of the magnetization of magnetic particles in a magnetic field, and proposes a magnetization model for calculating magnetic forces based on the real magnetic property curves of magnetic particles. Some factors affecting the trajectory of this were further analyzed. Our calculations may serve as an important guide for targeted medicine in the biomedical field and the targeted lubrication of magnetically lubricated particles. Based on the magnetic response of magnetic particles, the targeting of particles to a target area under the modulation of an external magnetic field has been used in many applications. An accurate kinematic model is helpful to achieve accurate targeting of magnetic particles and to investigate the factors influencing the motion of the particles. In the present paper, a segmental magnetization model was proposed based on the real magnetization process of superparamagnetic particles to calculate the magnetic force, and this was compared with a traditional magnetization model. The effects of magnetic field strength and particle diameter on the trajectory of magnetic particles in fluids under a magnetic field were further analyzed using a finite element analysis software. The simulation results show that changing the particle size only affected the velocity of the particles and did not affect the trajectory. When magnetic field strength changed, magnetic particles showed different trajectories. Notably, when the magnetic field force in the Y direction was too large, meaning the gravity could be neglected, the trajectory of the particles no longer changed when the magnetic field strength was varied. [ABSTRACT FROM AUTHOR]

It's challenging to use the machine vision to inspect the hot-rolled steel pipes with complex surface texture, uneven colour greyscale, and micro-cracks. On the basis of the principle of magnetic particle detection, a visual inspection method of steel pipe surface cracks based on the dry magnetic particle feature enhancement is proposed, in which the dry red magnetic particles are applied to the steel pipe's surface to form magnetic particle indication, and complementary colour images are captured in red and green light sources, and image difference is used to eliminate background noise and enhance magnetic particle indication features in view of the fact that the red light source improves and the green light source reduces the magnetic particle indication greyscale. Afterwards, the principle of selection of complementary colours and the detection principle are presented and analysed. Then, the magnetic particle images acquisition and the processing operations of the magnetic particle indication feature enhancement and crack segmentation are presented in detail. Finally, the feasibility of the method proposed in this paper is verified by experiments, and image segmentation metrics demonstrate that it has a good detection effect on the hot-rolled steel pipes with complex surface texture, uneven colour greyscale, and fuzzy cracks. [ABSTRACT FROM AUTHOR]

In this work, we investigate velocity magnetic particles by inextensible flows in sphere. We have advanced consequence of inextensible flows for velocity magnetic particles. Also, we characterize flows of electric field with Lorentz equation. Moreover, we get evolution equation of electric field in space. [ABSTRACT FROM AUTHOR]

An overexpression of sialic acid is an indicator of metastatic cancer, and selective detection of sialic acid shows potential for cancer diagnosis. Boronic acid is a promising candidate for this purpose because of its ability to specifically bind to sialic acid under acidic conditions. Notably, the binding strength can be easily modulated by adjusting the pH, which allows for a simple dissociation of the bound sialic acid. In this study, we developed 5-boronopicolinic acid (5-BPA)-modified magnetic particles (BMPs) to selectively capture sialic acid biomolecules. We successfully captured fetuin, a well-known sialoglycoprotein, on BMPs at >104 molecules/particle using an acetate buffer (pH 5.0). Facile dissociation then occurred when the system was changed to a pH 7.6 phosphate buffer. This capture-and-release process could be repeated at least five times. Moreover, this system could enrich fetuin by more than 20 times. In summary, BMPs are functional particles for facile purification and concentration through the selective capture of sialic acid proteins and can improve detection sensitivity compared with conventional methods. This technology shows potential for the detection of sialic acid overexpression by biological particles.

Introduction: The metabolic balance of amines is closely related to human health. It remains a great challenge to analyze amines with high-throughput and high-coverage.Methods: Polythioester-functionalized magnetic nanoprobes (PMPs) have been prepared under mild conditions and applied in chemoselective capture of amides. With the introduction of polythioester, PMPs demonstrate remarkably increased capture efficiency, leading to the dramatically improved sensitivity of mass spectrometry detection.Results: The analysis method with PMPs treatment has been applied in rapid detection of more than 100 amines in lung adenocarcinoma cell lines, mouse organ tissues, and 103 human serum samples with high-throughput and high-coverage. Statistical analysis shows that arginine biosynthesis differed between lung adenocarcinoma cell lines.Discussion: Phenylalanine, tyrosine and tryptophan biosynthesis differed between tissues. The combination indicators demonstrate a great diagnostic accuracy for distinguishing between health and lung disease subjects as well as differentiating the patients with benign lung disease and lung cancer. With powerful capture ability, low-cost preparation, and convenient separation, the PMPs demonstrate promising application in the intensive study of metabolic pathways and early diagnosis of disease.high-throughput and high-coverage. Here, polythioester-functionalized magnetic nanoprobes (PMPs) have been prepared under mild conditions and applied in chemoselective capture of amides. With the introduction of polythioester, PMPs demonstrate remarkably increased capture efficiency, leading to the dramatically improved sensitivity of mass spectrometry detection. The analysis method with PMPs treatment has been applied in rapid detection of more than 100 amines in lung adenocarcinoma cell lines, mouse organ tissues, and 103 human serum samples with high-throughput and high-coverage. Statistical analysis shows that arginine biosynthesis differed between lung adenocarcinoma cell lines. Phenylalanine, tyrosine and tryptophan biosynthesis differed between tissues. The combination indicators demonstrate a great diagnostic accuracy for distinguishing between health and lung disease subjects as well as differentiating the patients with benign lung disease and lung cancer. With powerful capture ability, low-cost preparation, and convenient separation, the PMPs demonstrate promising application in the intensive study of metabolic pathways and early diagnosis of disease.

Several parametric effects on the magnetic collection have been evaluated considering dimension, strength of external magnetic field, injected velocity and particle concentration in the working fluid. Besides, accidental environments, expected in the containment of nuclear power plants, have also been addressed for the capture efficiency. The capture efficiency is especially enhanced with magnetic particle size and magnetic field strength through increased magnetic force; the non-magnetic coating thickness and fluid velocity hinder the magnetic collection. Based on the assessment, the magnetic withdrawal system can effectively capture magnetic particles even under accidental environments. Withdrawal of multifunctional magnetic particles or filtering of magnetic impurities can be effectively realized through the system.

Electrochemical biosensors generally require the immobilization of recognition elements or capture probes on the electrode surface. This may limit their practical applications due to the complex operation procedure and low repeatability and stability. Magnetically assisted biosensors show remarkable advantages in separation and pre-concentration of targets from complex biological samples. More importantly, magnetically assisted sensing systems show high throughput since the magnetic materials can be produced and preserved on a large scale. In this work, we summarized the design of electrochemical biosensors involving magnetic materials as the platforms for recognition reaction and target conversion. The recognition reactions usually include antigen–antibody, DNA hybridization, and aptamer–target interactions. By conjugating an electroactive probe to biomolecules attached to magnetic materials, the complexes can be accumulated near to an electrode surface with the aid of external magnet field, producing an easily measurable redox current. The redox current can be further enhanced by enzymes, nanomaterials, DNA assemblies, and thermal-cycle or isothermal amplification. In magnetically assisted assays, the magnetic substrates are removed by a magnet after the target conversion, and the signal can be monitored through stimuli–response release of signal reporters, enzymatic production of electroactive species, or target-induced generation of messenger DNA. [ABSTRACT FROM AUTHOR]

This study presents preliminary computational and experimental findings on two alternative permanent magnet configurations helpful for magnetic drug administration in vivo. A numerical simulation and a direct experimental measurement of the magnetic induction on the magnet system's surface were used to map the magnetic field. In addition, the ferrite-type (grade Y35) and permanent neodymium magnets (grade N52) to produce powerful magnetic forces were also examined analytically and quantitatively. Ansys-Maxwell software and Finite Element Method Magnetism (FEMM) version 4.2 were used for all numerical computations in the current investigation. For both magnets, the generated magnetic fields were comparatively studied for targeting Fe particles having a diameter of 6 μm. The following findings were drawn from the present investigation: (i) the particle deposition on the vessel wall is greatly influenced by the intensity of the magnetic field, the magnet type, the magnet size, and the magnetic characteristics of the micro-sized magnetic particles (MSMPs); (ii) ferrite-type magnets might be employed to deliver magnetoresponsive particles to a target location, even if they are less powerful than neodymium magnets; and (iii) the results from the Computational Fluid Dynamics(CFD) models agree well with the measured magnetic field induction, magnetic field strength, and their fluctuation with the distance from the magnet surface. [ABSTRACT FROM AUTHOR]

Exfoliation syndrome presents as an accumulation of insoluble fibrillar aggregates that commonly correlates with age and causes ocular complications, most notably open-angle glaucoma. Despite advances in understanding the pathogenesis and risk factors associated with exfoliation syndrome, there has been no significant progress in curative pharmacotherapy of this disease. It is thought that the ability to target the fibrillar aggregates associated with exfoliation may offer a new therapeutic approach, facilitating their direct removal from affected tissues. Phage display techniques yielded two peptides (LPSYNLHPHVPP, IPLLNPGSMQLS) that could differentiate between exfoliative and non-affected regions of the human lens capsule. These peptides were conjugated to magnetic particles using click chemistry to investigate their ability in targeting and removing exfoliation materials from the anterior human lens capsule. The behavior of the fibrillar materials upon binding to these magnetic particles was assessed using magnetic pins and rotating magnetic fields of various strengths. Ex vivo studies showed that the magnetic particle-peptide conjugates could generate enough mechanical force to remove large aggregates of exfoliation materials from the lens capsule when exposed to a low-frequency rotating magnetic field (5000 G, 20 Hz). Biocompatibility of targeting peptides with and without conjugated magnetic particles was confirmed using MTT cell toxicity assay, live/dead cell viability assay, and DNA fragmentation studies on primary cultured human trabecular meshwork cells. This is a novel, minimally invasive, therapeutic approach for the treatment of exfoliation glaucoma via the targeting and removal of exfoliation materials that could be applied to all tissues within the anterior segment of the eye. [ABSTRACT FROM AUTHOR]

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The conducting polymer poly(2-(1H-pyrrole-1-yl)ethyl methacrylate (PPEMA) was synthesized by conventional atom transfer radical polymerization for the first time from free as well as surface-bonded alkyl bromide initiator. When grafted from the surface of carbonyl iron (CI) a substantial conducting shell on the magnetic core was obtained. Synthesis of the monomer as well as its polymer was confirmed using proton spectrum nuclear magnetic resonance (1H NMR). Polymers with various molar masses and low dispersity showed the variability of this approach, providing a system with a tailorable structure and brush-like morphology. Successful grafting from the CI surface was elucidate by transmission electron microscopy and Fourier-transform infrared spectroscopy. Very importantly, thanks to the targeted nanometer-scale shell thickness of the PPEMA coating, the magnetization properties of the particles were negligibly affected, as confirmed using vibration sample magnetometry. Smart elastomers (SE) consisting of bare CI or CI grafted with PPEMA chains (CI-PPEMA) and silicone elastomer were prepared and dynamic mechanical properties as well as interference shielding ones were investigated. It was found that short polymer chains grafted to the CI particles exhibited the plasticizing effect, which might be interesting from the magnetorheological point of view, and more interestingly, in comparison to the neat CI-based sample, it provided enhanced electromagnetic shielding of nearly 30 dB in thickness of 500 μm. Thus, SE containing the newly synthesized CI-PPEMA hybrid particles also exhibited considerably enhanced damping factor and proper mechanical performance, which make the material highly promising from various practical application points of view. [ABSTRACT FROM AUTHOR]

Metastable $\alpha '$ -Fe-N (12 at% N) and $\alpha '$ -Fe-C (12 at% C) are unique materials with a magnetocrystalline constant $K_{1}$ of + $5\times10$ 6 and $- 7\times10$ 6 erg/cm3, respectively, according to measurements based on thin films. Therefore, co-addition $\alpha ''$ -Fe $_{16}X_{2}$ ($X $ = N, C) particles are attractive as potential new soft magnetic materials because their magnetocrystalline constant can be varied by manipulating their N and C concentrations. However, introducing C interstitially into $\alpha $ -Fe particles by the carbonization process using a C-containing gas such as CO gas is difficult because the equilibrium phase Fe3C is easily generated. Therefore, we investigated various reaction routes of nitridation and carbonization, along with various C-containing gases, to prepare co-addition $\alpha ''$ -Fe16(N, C)2 particles. We obtained $\alpha ''$ -Fe16(N, C)2 particles using a route in which $\alpha $ -Fe was obtained by reduction of Fe3O4 particles, followed by nitridation to $\alpha ''$ -Fe16N2 and subsequent carbonization to $\alpha ''$ -Fe16(N, C)2. The amount of C particles after carbonization was measured to be 0.8 wt% (3.6 at%). This gas–solid reaction process based on the concept of using $\alpha ''$ -Fe16N2 as a material with an expanded $\alpha $ -Fe lattice is a useful method for the co-addition of interstitial N and C. [ABSTRACT FROM AUTHOR]

Due to the increasing crop losses caused by common and newly emerging phytopathogens, there is a pressing need for the development of rapid and reliable methods for phytopathogen detection and analysis. Leveraging advancements in biochemical engineering technologies and nanomaterial sciences, researchers have put considerable efforts on utilizing biofunctionalized magnetic micro- and nanoparticles (MPs) to develop rapid and reliable systems for phytopathogen detection. MPs facilitate the rapid, high-throughput analysis and in-field applications, while the biomacromolecules, which play key roles in the biorecognitions, interactions and signal amplification, determine the specificity, sensitivity, reliability, and portability of pathogen detection systems. The integration of MPs and biomacromolecules provides dimensionality- and composition-dependent properties, representing a novel approach to develop phytopathogen detection systems. In this review, we summarize and discuss the general properties, synthesis and characterization of MPs, and focus on biomacromolecule-functionalized MPs as well as their representative applications for phytopathogen detection and analysis reported over the past decade. Extensively studied bioreceptors, such as antibodies, phages and phage proteins, nucleic acids, and glycans that are involved in the recognitions and interactions, are covered and discussed. Additionally, the integration of MPs-based detection system with portable microfluidic devices to facilitate their in-field applications is also discussed. Overall, this review focuses on biomacromolecule-functionalized MPs and their applications for phytopathogen detection, aiming to highlight their potential in developing advanced biosensing systems for effective plant protection. Particularly attractive: This paper provides a comprehensive review of magnetic particles (MPs) functionalized with biomacromolecules for pathogen detections purposes, with a particular focus on their representative applications in phytopathogen detection and analysis. [Display omitted] • The properties, synthesis and characterization of magnetic particles (MPs) are introduced. • Biomacromolecules functionalized MPs used for phytopathogen detection are reviewed. • The biorecognitions mediated by proteins, nucleic acids and glycans are presented. • The integration of biofunctionalized MPs with portable devices is discussed. [ABSTRACT FROM AUTHOR]

The use of biomass and waste to produce adsorbent reduces the cost of water treatment. The bio-char of Sargassum oligocystum (BCSO) was modified with MnFe 2 O 4 magnetic particles and La-metal organic framework (MOF) to generate an efficient adsorbent (BCSO/MnFe 2 O 4 @La-MOF) for fluoride ions (F−) removal from aqueous solutions. The performance of BCSO/MnFe 2 O 4 @La-MOF was compared with BCSO/MnFe 2 O 4 and BCSO. The characteristics of the adsorbents were investigated using various techniques, which revealed that the magnetic composites were well-synthesized and exhibited superparamagnetic properties. The maximum adsorption efficiencies (BCSO: 97.84%, BCSO/MnFe 2 O 4 : 97.85%, and BCSO/MnFe 2 O 4 @La-MOF: 99.36%) were achieved under specific conditions of pH 4, F− concentration of 10 mg/L, and adsorbent dosage of 3, 1.5, and 1 g/L for BCSO, BCSO/MnFe 2 O 4 , and BCSO/MnFe 2 O 4 @La-MOF, respectively. The results demonstrated that the experimental data adheres to a pseudo-second-order kinetic model. The enthalpy, entropy, and Gibbs free energy were determined to be negative; thus, the F− adsorption was exothermic and spontaneous in the range of 25–50 °C. The equilibrium data of the process exhibited conformity with the Langmuir model. The maximum adsorption capacities of F− ions were determined as 10.267 mg/g for BCSO, 14.903 mg/g for the BCSO/MnFe 2 O 4 , and 31.948 mg/g for BCSO/MnFe 2 O 4 @La-MOF. The K F and A T values for the F− adsorption were obtained at 21.03 mg/g (L/mg)1/n and 100 × 10+9 L/g, indicating the pronounced affinity of the BCSO/MnFe 2 O 4 @La-MOF towards F− than other samples. The significant potential of the BCSO/MnFe 2 O 4 @La-MOF magnetic composite for F− removal from industrial wastewater, makes it suitable for repeated utilization in the adsorption process. [Display omitted] • The algal biochar was amended with MnFe 2 O 4 , Lanthanum, and MOF from PET waste. • The magnetic novel composite was used to remove fluoride from water and wastewater. • More than 99% of fluoride was removed at pH 4, and F− content of 10 mg/L. • F− removal followed pseudo-second-order and the Langmuir models (R2 > 0.99). • The reclaimable composite was effectively removed F− from industrial wastewater. [ABSTRACT FROM AUTHOR]

Based on the magnetic response of magnetic particles, the targeting of particles to a target area under the modulation of an external magnetic field has been used in many applications. An accurate kinematic model is helpful to achieve accurate targeting of magnetic particles and to investigate the factors influencing the motion of the particles. In the present paper, a segmental magnetization model was proposed based on the real magnetization process of superparamagnetic particles to calculate the magnetic force, and this was compared with a traditional magnetization model. The effects of magnetic field strength and particle diameter on the trajectory of magnetic particles in fluids under a magnetic field were further analyzed using a finite element analysis software. The simulation results show that changing the particle size only affected the velocity of the particles and did not affect the trajectory. When magnetic field strength changed, magnetic particles showed different trajectories. Notably, when the magnetic field force in the Y direction was too large, meaning the gravity could be neglected, the trajectory of the particles no longer changed when the magnetic field strength was varied.

Bifunctional core-shell magnetic fluorescent microspheres have been synthesized via a facile interface Pechini-type sol-gel method. Benefited from the uniform core-shell structure, large magnetization, and strong fluorescence emission, the Fe 3 O 4 @YVO 4 :Eu3+ microspheres were successfully applied as effective and sensitive markers to recognize latent fingerprint on a variety of substrates with fine lines, low background interference, high contrast, and clear detail features of 3 levels, indicating promising application in personal identification. [Display omitted] Latent fingerprint recognition technique has received increasing attention because it helps to precisely identify human information for many applications. In this study, bifunctional core-shell magnetic fluorescent microspheres have been synthesized via a facile interface Pechini-type sol-gel method using citric acid and polyethylene glycol as chelating agent and cross-linking agent, respectively. The obtained Fe 3 O 4 @YVO 4 :Eu3+ microspheres possess a typical core-shell structure, large magnetization, and strong fluorescence emission. The surface morphology and roughness of the microspheres can be flexibly tuned by controlling the multistep interface deposition process and subsequent calcination temperatures. Due to their well-integrated bifunctionalities, these magnetic fluorescent microspheres show outstanding performance in the visualization of latent fingerprints on various substrates with high definition and excellent anti-interference, and therefore they have great potential for application in identity recognition. [ABSTRACT FROM AUTHOR]

The ELISA is the most worldwide method for immunoassay. However, the ELISA is losing ground due to low reproducibility of manual experimental processes in both R&D and IVD areas. An automated platform is a good solution, but there are still limitations owning to extremely high cost and requiring large space to set up especially for a small size laboratory. Here, we present a novel all-in-one platform called "VEUS" settable on the laboratory table that offers comprehensive automation of the entire multiplex immunoassay process by exploiting antibody conjugated magnetic particles, quality control and then immunoanalytical reaction, thereby enhancing detection sensitivity and high reproducibility. As a proof of concept, the system exhibits a sensitive LOD of 0.6 and 3.1 pg mL -1 within 1 h run, comparable precision that of molecular diagnostic systems based on PCR method, enabling rapid multiplex diagnosis of Influenza A, Influenza B, and COVID-19 viruses with similar symptoms. Through automation by the all-in-one system, it can be used by novice users, something innovative for immunoassays, relying heavily on user experience. Furthermore, it can contribute to streamline entire immunoassay processes of diverse biomarkers with high reproducibility and convenience in laboratories., (© 2024 The Authors. Biotechnology Journal published by Wiley‐VCH GmbH.)

Magnetic assembly at the nanoscale level brings potential possibilities in obtaining novel delicate nanostructures with unique physical, photonic or electronic properties. Interface surfactant micelle-directed assembly strategy holds great promising in fabricating ordered mesoporous materials with multifunctionality and pore parameter tunability. Combing these, herein, one-dimensional (1D) nanochains with well-aligned silica-coated magnetic particles as core and mesoporous aluminosilicate as shell are rational fabricated for the first time through magnetic field induced interface coassembly in biliquid system followed by the incorporation of Al species via in-situ chemical modification and transformation strategy. The obtained magnetic mesoporous aluminosilicate nanochains (MMAS-NCs) possess well-defined core-shell-shell sandwich nanostructure, tunable perpendicular mesopore channels in the shell (2.7–7.6 nm), high surface area (359 m2·g−1), abundant acidic sites, and superparamagnetism with a magnetization saturation of 13.8 emu·g−1. Thanks to the unique properties, the MMAS-NCs exhibit excellent performance in acting as magnetically recyclable superior solid acid catalysts and nanostirrers with high conversion of over 96.8%, selectivity of 95.0% in the deprotection reaction of benzaldehyde dimethylacetal to benzaldehyde. Moreover, MMAS-NCs exhibit an interesting pore size effect on the catalytic activity, namely, in the pore size range of 2–8 nm, the catalysts with larger pores show significantly enhanced catalytic activity due to the balanced mass transport and density of surface active sites. [ABSTRACT FROM AUTHOR]

Electrochemical biosensors generally require the immobilization of recognition elements or capture probes on the electrode surface. This may limit their practical applications due to the complex operation procedure and low repeatability and stability. Magnetically assisted biosensors show remarkable advantages in separation and pre-concentration of targets from complex biological samples. More importantly, magnetically assisted sensing systems show high throughput since the magnetic materials can be produced and preserved on a large scale. In this work, we summarized the design of electrochemical biosensors involving magnetic materials as the platforms for recognition reaction and target conversion. The recognition reactions usually include antigen–antibody, DNA hybridization, and aptamer–target interactions. By conjugating an electroactive probe to biomolecules attached to magnetic materials, the complexes can be accumulated near to an electrode surface with the aid of external magnet field, producing an easily measurable redox current. The redox current can be further enhanced by enzymes, nanomaterials, DNA assemblies, and thermal-cycle or isothermal amplification. In magnetically assisted assays, the magnetic substrates are removed by a magnet after the target conversion, and the signal can be monitored through stimuli–response release of signal reporters, enzymatic production of electroactive species, or target-induced generation of messenger DNA.

Among the many factors causing particle sedimentation, three principal ingredients are heavily involved: magnetic particles, a carrier liquid (base oil), and additives (surfactant). Therefore, many works have been carried out to improve the sedimentation stability of magnetorheological fluids (MRFs) by adopting the three methods. In the particle modification stage, the weight concentration, size distribution, particle shape, coated materials, and combinations of different sizes of the particles have been proposed, while for the modification of the carrier liquid, several works on the density increment, wettability control, and the use of natural oils, lubricant oil, grease, and ethyl- and butyl-acetate oils have been undertaken. Recently, in certain recipes to improve sedimentation stability, some additives such as aluminum stearate were used to increase the redispersibility of the aggregated particles. In addition, several works using more than two recipes modifying both the particles and base oils are being actively carried out to achieve higher sedimentation stability. This review article comprehensively introduces and discuses the recipes to improve sedimentation stability from the aspects of the three ingredients. A few conceptual methodologies to prevent the sedimentation occurring via a bottle’s storage on the shelves of the application systems are also presented, since, to the author’s knowledge, there has not been a report on this issue. These are challenging works to be explored and developed for successful application systems’ MRFs.

This study presents preliminary computational and experimental findings on two alternative permanent magnet configurations helpful for magnetic drug administration in vivo. A numerical simulation and a direct experimental measurement of the magnetic induction on the magnet system’s surface were used to map the magnetic field. In addition, the ferrite-type (grade Y35) and permanent neodymium magnets (grade N52) to produce powerful magnetic forces were also examined analytically and quantitatively. Ansys-Maxwell software and Finite Element Method Magnetism (FEMM) version 4.2 were used for all numerical computations in the current investigation. For both magnets, the generated magnetic fields were comparatively studied for targeting Fe particles having a diameter of 6 μm. The following findings were drawn from the present investigation: (i) the particle deposition on the vessel wall is greatly influenced by the intensity of the magnetic field, the magnet type, the magnet size, and the magnetic characteristics of the micro-sized magnetic particles (MSMPs); (ii) ferrite-type magnets might be employed to deliver magnetoresponsive particles to a target location, even if they are less powerful than neodymium magnets; and (iii) the results from the Computational Fluid Dynamics( CFD) models agree well with the measured magnetic field induction, magnetic field strength, and their fluctuation with the distance from the magnet surface.

The novel magnetic bio-char(MBC), which was derived from sewage sludge in municipal wastewater treatment plant after pyrolysis and Fe2+/Fe3+ modification by loading nano-sized iron oxide particles.The MBC can be used for the adsorption of heavy metal ions in aqueous system remediation. The physical/chemical characteristics of MBC were revealed by VSM, SEM-EDS, XRD, FTIR and batch adsorption experiments. The results showed that the nano-sized γ-Fe2O3 particles grew on the surface of bio-char uniformly, and the saturation magnetization of MBC reached 13.53Am²/kg. In adsorption experiments, when the dosage of MBC was 1.25g/L, adsorption time was 24h, pH was 5.0, the adsorption capacity was 67.68mg/g which increased by 60.08% than that of bio-char. The Langmuir isothermal and pseudo-second-order model can describe adsorption process of magnetic bio-char well. The MBC derived from sewage sludge has significant adsorption capacity, which is easy to separate from aqueous system. This disposition can recycle solid waste to pollution treatment. [ABSTRACT FROM AUTHOR]

Extensive research is currently underway to devise effective strategies for the isolation of circulating tumor cells (CTCs) from blood samples. The utilization of magnetic particles and magnet as a means for this separation process is garnering increased attention within this field. However, when utilizing fixed magnets to capture cancer cells with attached magnetic particles, the inability to control the magnetic field may result in cellular damage due to the strong magnetic field compressing the magnetic particles. In this study, we developed a hybrid system that leverages electromagnetic coils to modulate the strength of the magnetic field from the magnets within a microfluidic channel, enabling real-time control of cancer cells with attached magnetic particles. Through the strategic application of electromagnetic coils, we achieved precise control over the magnet's position, thereby enabling real-time observation of the cancer cell within the microfluidic channel. Additionally, this approach facilitated the release of captured cancer cells from the magnet. The isolated cells could then be cultured to assess individualized drug responses, and evaluate their reactivity to the treatment. Through the implementation of this novel technique, we anticipate that the real-time capture and analysis of CTCs from blood samples will enable more efficient and effective diagnostics and treatment monitoring, ultimately improving patient outcomes. [Display omitted] • A hybrid system of permanent magnets and electromagnets was developed for effective control of a strong magnetic field. • Magnetic fields are utilized to successfully isolate cancer cells, attached to magnetic particles, within a microfluidic channel under real-time monitoring. • The captured cancer cells were successfully cultivated, allowing for subsequent drug response evaluation. [ABSTRACT FROM AUTHOR]

The conducting polymer poly(2-(1H-pyrrole-1-yl)ethyl methacrylate (PPEMA) was synthesized by conventional atom transfer radical polymerization for the first time from free as well as surface-bonded alkyl bromide initiator. When grafted from the surface of carbonyl iron (CI) a substantial conducting shell on the magnetic core was obtained. Synthesis of the monomer as well as its polymer was confirmed using proton spectrum nuclear magnetic resonance (1H NMR). Polymers with various molar masses and low dispersity showed the variability of this approach, providing a system with a tailorable structure and brush-like morphology. Successful grafting from the CI surface was elucidate by transmission electron microscopy and Fourier-transform infrared spectroscopy. Very importantly, thanks to the targeted nanometer-scale shell thickness of the PPEMA coating, the magnetization properties of the particles were negligibly affected, as confirmed using vibration sample magnetometry. Smart elastomers (SE) consisting of bare CI or CI grafted with PPEMA chains (CI-PPEMA) and silicone elastomer were prepared and dynamic mechanical properties as well as interference shielding ones were investigated. It was found that short polymer chains grafted to the CI particles exhibited the plasticizing effect, which might be interesting from the magnetorheological point of view, and more interestingly, in comparison to the neat CI-based sample, it provided enhanced electromagnetic shielding of nearly 30 dB in thickness of 500 μm. Thus, SE containing the newly synthesized CI-PPEMA hybrid particles also exhibited considerably enhanced damping factor and proper mechanical performance, which make the material highly promising from various practical application points of view.