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An exciting prospect in the field of magnetic fluid hyperthermia (MFH) has been the integration of noble rare earth elements with biopolymers (chitosan/dextran) that have optimum structures to tune specific effects on magnetic nanoparticles (MNPs). Remarkably, it has been demonstrated that dipole–dipole interactions have a significant influence on nanoparticle dynamics. In this article, we present an exhaustive scrutiny of dipolar interactions and how this affects the efficiency of MFH applications. In particular, we prepare chitosan and dextran-coated Tb-doped MNPs and study whether it is possible to increase the heat released by controlling the dipole–dipole interactions. It has been indicated that even moderate control of agglomeration may substantially impact the structure and magnetization dynamics of the system. Besides estimating the specific loss power value, our findings provide a deep insight into the relaxation mechanisms and bring to light how to tune the self-heating efficacy towards magnetic hyperthermia. [ABSTRACT FROM AUTHOR]

Nanomaterials have demonstrated a wide range of applications and amongst nanomaterials, most of the research has mainly focused on nanoparticles as they can be easily prepared and manipulated. The magnetic properties of certain magnetic nanoparticles have attracted a lot of interest in environmental applications. However, because of their great vulnerability to chemical and physical activity, their magnetic characteristics deteriorate. These nanoparticles are being progressively attempted to be encapsulated by a green organic matrix, which greatly improves usefulness, stability, and affordability, and reduces back toxicity. In this investigation, iron oxide (IO) nanoparticles were prepared by a co-precipitation method and these bear IO particles were stabilized by green synthesized silver nanoparticles to produce IO/Ag nanocomposite particles. The nano size of the prepared particles was confirmed by FE-SEM and TEM analysis. Incorporation of silver nanoparticles (AgNPs) on IO particles was confirmed by UV-Vis, XRD, TGA, and VSM. The improved stability of the magnetic particles was confirmed by DLS and zeta potential. Using the reducing agent NaBH4, the catalytic reduction ability of the IO/Ag nanocomposite particles is investigated in relation to the degradation of Congo Red, a model anionic azo dye. When 40 μg mL−1 of IO/Ag particles were used, complete degradation of 20 mL of CR (0.1 mM) dye solution was accomplished in 2 minutes. The particles also demonstrated moderate antibacterial activity against four pathogens and good DPPH free radical scavenging activity, with 94% scavenging recorded at a concentration of 100 μg mL−1 particles. [ABSTRACT FROM AUTHOR]

Iron oxide dust, discarded as industrial waste, has been used here to fabricate magnetic iron oxide nanoparticles (Fe3O4-NPs). We have proposed the thermo-catalytic reduction of carbon dioxide (CO2) using Fe3O4-NPs in the presence of H2O2 to get acetic acid (AcOH) at near ambient conditions (100 °C, 10 bar) with a maximum yield of ∼0.4 M in a batch-reactor. The importance of H2O2 can be described as it facilitates the production of higher concentrations of OH˙ and H+/˙, which consequently supports the synthesis of AcOH. [ABSTRACT FROM AUTHOR]

In this study, Mg1-xCoxFe2O4 (0

Background: The delivery of therapeutic nucleic acids, such as small interfering RNA (siRNA) and antisense oligonucleotides (ASO) into cells, is widely used in gene therapy. Gold nanoparticles (AuNPs) have proved to be effective in delivering silencing moieties with high efficacy. Moreover, AuNPs offer the possibility of spatial–temporal triggering of cell uptake through light irradiation due to their unique optical properties. Our study focuses on the use of AuNPs as improved vectorisation agents through mild photothermy triggered by visible light irradiation. This method promotes the transfection of oligonucleotides for gene silencing in 2D cells and more complex 3D spheroids. Results: Improving gene silencing strategies in 3D cell cultures is crucial since it provides more effective in vitro models to study cellular responses that closely resemble the in vivo tumour microenvironment. We demonstrate the potential of mild photothermy by effectively silencing the GFP gene in 2D cell cultures: HCT116 and MCF-7. Then we showed that mild photothermy could be effectively used for silencing the c-MYC oncogene transcript, which is greatly overexpressed in cancer cells. A decrease of 25% and 30% in c-MYC expression was observed in HCT116 2D cells and 7-day 3D spheroids, respectively. Conclusions: In summary, our findings offer a novel transfection approach for gene therapy applications in 2D and 3D tumour models. This approach is based on the use of mild photothermy mediated by AuNPs combined with visible laser irradiation that might pave the way for the spatial–temporal control of gene modulation. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) has attracted much attention in tumor-targeted drug delivery due to its ability to specifically bind to the CD44 cellular receptor, which is widely expressed on cancer cells. We present HA-capped magnetic nanoparticles (HA-MNPs) obtained via the co-precipitation method, followed by the electrostatic adsorption of HA onto the nanoparticles' surfaces. A theoretical study carried out with the PM3 method evidenced a dipole moment of 3.34 D and negatively charged atom groups able to participate in interactions with nanoparticle surface cations and surrounding water molecules. The ATR-FTIR spectrum evidenced the hyaluronic acid binding to the surface of the ferrophase, ensuring colloidal stability in the water dispersion. To verify the success of the synthesis and stabilization, HA-MNPs were also characterized using other investigation techniques: TEM, EDS, XRD, DSC, TG, NTA, and VSM. The results showed that the HA-MNPs had a mean physical size of 9.05 nm (TEM investigation), a crystallite dimension of about 8.35 nm (XRD investigation), and a magnetic core diameter of about 8.31 nm (VSM investigation). The HA-MNPs exhibited superparamagnetic behavior, with the magnetization curve showing saturation at a high magnetic field and a very small coercive field, corresponding to the net dominance of single-domain magnetic nanoparticles that were not aggregated with reversible magnetizability. These features satisfy the requirement for magnetic nanoparticles with a small size and good dispersibility for long-term stability. We performed some preliminary tests regarding the nanotoxicity in the environment, and some chromosomal aberrations were found to be induced in corn root meristems, especially in the anaphase and metaphase of mitotic cells. Due to their properties, HA-MNPs also seem to be suitable for use in the biomedical field. [ABSTRACT FROM AUTHOR]

In magnetic nanoparticle hyperthermia, the magnetic nanoparticles (MNPs) start oscillations when they are exposed to an alternating magnetic field, which may generate ultrasound waves. These resulting oscillations of nanoparticles can lead to the movement of drug carrier liposomes. In this study, a multiphysics coupling model of magnetic nanoparticle behavior in an alternating magnetic field was developed, implementing solid mechanics compliance parameters and piezomagnetic coupling matrices. A detailed sensitivity study was conducted to examine the effects of size and elastic modulus of MNPs, distribution and distance between two MNPs, elasticity and viscosity of the glycerol medium and mesh element sizes on the output displacement signals of MNPs. The results indicated that magnetic nanoparticles undergo some displacements when they are exposed to an alternating magnetic field. These oscillations may generate ultrasound waves, though the amount of displacement for each nanoparticle is negligibly small. It is expected that aggregated nanoparticles result in much higher oscillations. [ABSTRACT FROM AUTHOR]

Objectives: Cancer-related death rates account for approximately one-third of all deaths, and this rate is increasing remarkably every year. In this study, we examined the dose enhancement factor (DEF) in the tumor and surrounding tissues by adding different concentrations of silver nanoparticles (AgNPs) to the brain tumor using the Monte Carlo (MC) technique. Methods: This study used MCNP6.2 simulation software. A Planning Target Volume (PTV) of 1 × 1 × 1 cm3 was placed in the center of a cubic cranial model with dimensions of 5 × 5 × 5 cm3. Five different simulations were initially generated using the simple method. These simulations included pure PTV and PTV consisting of 4 different silver concentrations (5, 10, 20, and 30 mg/g). Additionally, a model was created using the nanolattice method, considering the size, position, and distribution of the AgNPs. Irradiation was performed using a source with a 6 MV linac photon spectrum. Measurements were performed using the *f8 tally, and DEF values were calculated. Results: In the simulation study using the simple method, the DEF value of PTV increased linearly with concentration, whereas the DEF values were lower than the simulation results with the nanolattice model (1.9 vs 1.4 for 30 mg/g NP concentration). Performing the simple method, we observed no remarkable dose increase in lateral OARs surrounding PTV. While a remarkable dose decrease was observed in distal OARs, a dose increase in the proximal OAR was observed, which was consistent with that of PTV. However, according to the results obtained by performing the nanolattice method, the dose increase was observed in both the proximal OAR and the distal OAR and was similar to that of PTV. Conclusion: While enhancing the dose in the tumor by adding NPs into the tumor, it is essential to consider whether it also increases the OAR dose. In addition, simulation studies on NPs showed that the dose increase varied significantly with particle size, position, and distribution. Hence, these factors should be considered carefully. [ABSTRACT FROM AUTHOR]

The modern global trend toward sustainable processes that meet the requirements of "green chemistry" provides new opportunities for the broad application of highly active, selective, and specific enzymatic reactions. However, the effective application of enzymes in industrial processes requires the development of systems for the remote regulation of their activity triggered by external physical stimuli, one of which is a low-frequency magnetic field (LFMF). Magnetic nanoparticles (MNPs) transform the energy of an LFMF into mechanical forces and deformations applied to enzyme molecules on the surfaces of MNPs. Here, we demonstrate the up- and down-regulation of two biotechnologically important enzymes, yeast alcohol dehydrogenase (YADH) and soybean formate dehydrogenase (FDH), in aggregates with gold-covered magnetic nanoparticles (GCMNPs) triggered by an LFMF. Two types of aggregates, "dimeric" (with the enzyme attached to several GCMNPs simultaneously), with YADH or FDH, and "monomeric" (the enzyme attached to only one GCMNP), with FDH, were synthesized. Depending on the aggregate type ("dimeric" or "monomeric"), LFMF treatment led to a decrease (down-regulation) or an increase (up-regulation) in enzyme activity. For "dimeric" aggregates, we observed 67 ± 9% and 47 ± 7% decreases in enzyme activity under LFMF exposure for YADH and FDH, respectively. Moreover, in the case of YADH, varying the enzyme or the cross-linking agent concentration led to different magnitudes of the LFMF effect, which was more significant at lower enzyme and higher cross-linking agent concentrations. Different responses to LFMF exposure depending on cofactor presence were also demonstrated. This effect might result from a varying cofactor binding efficiency to enzymes. For the "monomeric" aggregates with FDH, the LFMF treatment caused a significant increase in enzyme activity; the magnitude of this effect depended on the cofactor type: we observed up to 40% enzyme up-regulation in the case of NADP+, while almost no effect was observed in the case of NAD+. [ABSTRACT FROM AUTHOR]

In this work, a series of PEGylated manganese-zinc ferrite mixed (PEG-Mn1-xZnxFe2O4) nanoparticles with varying concentrations of zinc ions (x = 0.0, 0.25, 0.4, 0.5, 0.75, 1.0) were synthesized using a solvothermal approach to investigate their physicochemical and magnetic hyperthermia properties through a range of analytical techniques, including TEM, XRF, XRD, FTIR, VSM, and magnetic hyperthermia. The PEG-Mn1-xZnxFe2O4 nanoparticles exhibited a nearly spherical shape and diameters less than 30 nm. The particle size decreased from 27 to 11.6 nm with an increasing amount of zinc (x = 0.0–0.5). The saturation magnetization (MS) value decreased with the rising Zn content, ranging from 77.8 to 30.7 emu/g. The addition of zinc led to a reduction in the specific absorption rate (SAR) of the material. This decrease in the SAR parameter was associated with a decline in the intrinsic loss power (ILP) value, varying from 0.264 nH m2/kg for MnFe2O4 to 0.037 nH m2/kg for ZnFe2O4. Consequently, these PEG-Mn1-xZnxFe2O4 nanoparticles exhibit potential as candidates for magnetic fluid hyperthermia applications. [ABSTRACT FROM AUTHOR]

It has been observed that polyvalent metal ions can mediate the adsorption of DNA on polydopamine (PDA) surfaces. Exploiting this, we used two divalent metal ions (Mg2+ or Ca2+) to promote the adsorption of fluorescence-labelled ochratoxin A (OTA) aptamers on PDA-coated magnetic nanoparticles (Fe3O4@PDA). Based on the different adsorption affinities of free aptamers and OTA-bound aptamers, a facile assay method was established for OTA detection. The aptamers adsorbed on Fe3O4@PDA were removed via simple magnetic separation, and the remaining aptamers in the supernatant exhibited a positive correlation with the OTA concentration. The concentrations of Mg2+ and Ca2+ were finely tuned to attain the optimal adsorption affinity and sensitivity for OTA detection. In addition, other factors, including the Fe3O4@PDA dosage, pH, mixing order, and incubation time, were studied. Finally, under optimized conditions, a detection limit (3σ/s) of 1.26 ng/mL was achieved for OTA. Real samples of spiked red wine were analysed with this aptamer-based method. This is the first report of regulating aptamer adsorption on the PDA surface with polyvalent metal ions for OTA detection. By changing the aptamers, the method can be easily extended to other target analytes. [ABSTRACT FROM AUTHOR]

This study explored the effectiveness of nasal administration in delivering magnetic nanoparticles into the brain for magnetic particle imaging of target regions. Successful delivery of iron oxide nanoparticles, which serve as contrast agents, to specific sites within the brain is crucial for achieving magnetic particle imaging. Nasal administration has gained attention as a method to bypass the blood-brain barrier and directly deliver therapeutics to the brain. In this study, we investigated surface modification techniques for administering magnetic nanoparticles into the nasal cavity, and provided experimental validation through in vivo studies. By compositing magnetic nanoparticles with gold nanoparticles, we enabled additional surface modification via Au S bonds without compromising their magnetic properties. The migration of the designed PEGylated magnetic nanoparticles into the brain following nasal administration was confirmed by magnetization measurements. Furthermore, we demonstrated the accumulation of these nanoparticles at specific target sites using probe molecules immobilized on the PEG terminus. Thus, the efficacy of delivering magnetic nanoparticles to the brain via nasal administration was demonstrated in this study. The findings of this research are expected to contribute significantly to the realization of magnetic particle imaging of target regions within the brain. This study investigates efficient brain delivery of magnetic nanoparticles through nasal administration for magnetic particle imaging. Successful delivery to specific brain sites was confirmed, showing potential for improved imaging in target brain regions. [Display omitted] [ABSTRACT FROM AUTHOR]

It can be observed that magnetic iron-oxide nanoparticles are increasingly used in bioassay methods. This is due to their stability in aqueous solutions, ease of functionalization, biocompatibility and very low toxicity. Here, we show that the recent discovery of the ability of magnetic nanoparticles to self-assemble into 2D structures of ordered chains may be exploited for bioassays. This would open up the possibility of controlled immobilization of proteins, enzymes, DNA or RNA and other molecular systems on spatially ordered nanostructures. In this work, fluorescein was used as an example. Also shown is the possibility of using Raman spectroscopy to analyze material accumulated on such structures. The observed formation of regularly spaced chains of magnetic nanoparticles takes place during the drying process of a thin layer of magnetic liquid placed on an appropriately prepared low-density polyethylene (LDPE) film. [ABSTRACT FROM AUTHOR]

One of the main challenges in improving the efficacy of conventional chemotherapeutic drugs is that they do not reach the cancer cells at sufficiently high doses while at the same time affecting healthy tissue and causing significant side effects and suffering in cancer patients. To overcome this deficiency, magnetic nanoparticles as transporter systems have emerged as a promising approach to achieve more specific tumour targeting. Drug-loaded magnetic nanoparticles can be directed to the target tissue by applying an external magnetic field. However, the magnetic forces exerted on the nanoparticles fall off rapidly with distance, making the tumour targeting challenging, even more so in the presence of flowing blood or interstitial fluid. We therefore present a computational model of the capturing of magnetic nanoparticles in a test setup: our model includes the flow around the tumour, the magnetic forces that guide the nanoparticles, and the transport within the tumour. We show how a model for the transport of magnetic nanoparticles in an external magnetic field can be integrated with a multiphase tumour model based on the theory of porous media. Our approach based on the underlying physical mechanisms can provide crucial insights into mechanisms that cannot be studied conclusively in experimental research alone. Such a computational model enables an efficient and systematic exploration of the nanoparticle design space, first in a controlled test setup and then in more complex in vivo scenarios. As an effective tool for minimising costly trial-and-error design methods, it expedites translation into clinical practice to improve therapeutic outcomes and limit adverse effects for cancer patients. [ABSTRACT FROM AUTHOR]

In the ever-evolving field of medical diagnostics and imaging, the development of efficient and versatile contrast agents remains pivotal. This study presents a pioneering approach to synthesize superparamagnetic magnetite nanoparticles (SM-NPs) derived from natural ore using an environmentally friendly, green chemistry approach. These SM-NPs exhibit exceptional magnetic properties, surpassing all other forms of iron oxide, making them a novel and promising multi-imaging agent for various biomedical applications. The SM-NPs were synthesized with high purity from naturally occurring magnetite, sourced from the Earth's crust. Characterization via X-ray diffraction (XRD) confirmed the cubic spinel ferrites structure of the sample, with an average particle size of 21.24 nm. Fourier-Transform Infrared Spectroscopy (FT-IR) revealed the presence of elemental functional groups, further supporting the material's suitability for biomedical use. Morphological analysis using field emission scanning electron microscopy with energy-dispersive X-ray analysis (FESEM-EDX) unveiled agglomerated spherical particles ranging in size from 60 to 80 nm. The elemental composition analysis via EDX demonstrated predominant iron (Fe) and oxygen (O) elements at concentrations of 75.55% and 20.76%, respectively. The magnetic properties of the SMNPs were assessed using a vibrating sample magnetometer (VSM), revealing a superparamagnetic behavior, as evidenced by the M-H plot. Furthermore, X-ray imaging exhibited a significant signal, even with just 40 mg of the substance, suggesting its potential as a robust contrast agent. Complementary findings from computed tomography (CT) and magnetic resonance imaging (MRI) scans demonstrated substantial absorption capabilities, even at relatively low concentrations of SM-NPs. These remarkable attributes position the green-synthesized SM-NPs as a highly versatile and efficient multi-imaging agent for various biomedical applications. This single nanomaterial can revolutionize disease diagnosis, treatment monitoring, and drug delivery within the biomedical field, offering a greener and more effective approach to medical imaging and diagnostics. [ABSTRACT FROM AUTHOR]

The work provides a study of the effects of an external uniform magnetic field on the underwater pulsed discharge burning process. The presence of a magnetic field affects the waveforms of current and voltage, resulting in a decrease in amplitude values and frequency of discharge pulses. The presence of an external magnetic field was found to affect processes of the synthesis of iron oxide powders. Different polymorphic modifications of Fe2O3 were obtained depending on the orientation of the magnetic field. The formation of larger iron oxide nanoparticles is facilitated by the magnetic field. The release of desublimation energy, accompanied by heating, encourages the increasing the degree of crystallinity of samples in the presence of a magnetic field. Shown, that the presence of an external magnetic field has significant effects on the underwater pulsed discharge process, altering the electrical properties of the discharge and influencing the synthesis of oxide nanoparticles. [ABSTRACT FROM AUTHOR]

The adsorption of malachite green (MG) from aqueous solutions was performed using a combination of magnetic chitosan nanoparticles coated with triglycine (Gly-Gly-Gly) and 2-mercaptoethylamine hydrochloride. These processes were performed sequentially using a co-precipitation method followed by coating with desired functional groups. Chitosan magnetic products and modified products were characterized by transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), thermogravimetric analysis (TGA), Energy dispersive X-ray spectroscopy (EDX), vibrating sample magnetometer (VSM), Porosimeter (BET instrument) and X-ray diffraction spectroscopy (XRD).The ideal parameters for removal efficiency tested were pH, MG concentration, sorbent dosage, time, sonication or shaking, and temperature. Characterization results of the nanoadsorbent using TEM, FE-SEM, and VSM indicated that the synthesized nanoparticles was polycrystalline and tends to aggregate due to its high super paramagnetic properties before coating with stabilizing functional groups. BET surface area of (CSMNP) was 36.5473 m2/g while the BET surface area for the modified product (CSMNPTSC + TGly + 2-MEA) was 16.0073 m2/g. In addition, EDX characterization showed that the modified nanoadsorbent was polycrystalline and had three major peak patterns (110), (201), and (210) as indicators of the crystalline formation of chitosan nonmaterial. On the other hand, SAED pattern analysis on the TEM revealed that both chitosan magnetic nanoadsorbent and its modified products were polycrystalline nanoparticles with size range of 48 and 59 nm respectively. The dynamic simulation of Malachite Green is almost complete and this was mostly predicted by secondorder pseudo model with R2 = 0.991. Results of isotherm studies showed that adsorption of MG to magnetic chitosan nanoparticles coated with triglycine (Gly-Gly-Gly) and 2-mercaptoethylamine hydrochloride was possible. Experimental adsorption process results showed that, under optimal conditions, high pH and shorter time, favours MG adsorption with approximately 99.9% MG removal efficiency. The fabricated nanoadsorbents have been found to be an effective in water purification technology. The Gibbs free energy of adsorption, a thermodynamic parameter, also showed that the reaction proceeded thermodynamically favourably and spontaneously due to the large negative value of the reaction. This affirms for the successful adsorption of MG in aqueous solutions. [ABSTRACT FROM AUTHOR]

Nanoparticles have been developed as imaging contrast agents, heat absorbers to confine energy into targeted tumors, and drug carriers in advanced cancer treatment. It is crucial to achieve a minimal concentration of drug-carrying nanostructures or to induce an optimized nanoparticle distribution in tumors. This review is focused on understanding how local or whole-body heating alters transport properties in tumors, therefore leading to enhanced nanoparticle delivery or optimized nanoparticle distributions in tumors. First, an overview of cancer treatment and the development of nanotechnology in cancer therapy is introduced. Second, the importance of particle distribution in one of the hyperthermia approaches using nanoparticles in damaging tumors is discussed. How intensive heating during nanoparticle hyperthermia alters interstitial space structure to induce nanoparticle migration in tumors is evaluated. The next section reviews major obstacles in the systemic delivery of therapeutic agents to targeted tumors due to unique features of tumor microenvironments. Experimental observations on how mild local or whole-body heating boosts systemic nanoparticle delivery to tumors are presented, and possible physiological mechanisms are explored. The end of this review provides the current challenges facing clinicians and researchers in designing effective and safe heating strategies to maximize the delivery of therapeutic agents to tumors.

The use of magnetic nanothermometry faces challenges in noninvasive thermal monitoring during hyperthermia therapy due to the impact of the biological protein corona. Herein, we present an advanced magnetic nanothermometry model that incorporates the linear and cubic susceptibility phases, ensures robustness against hydrodynamic variations, maintains concentration independence, and can adapt to diverse magnetic field intensities. In this work, we studied five types of particles with comparable core structures (single- and multi-core) and chemical compositions (carboxyl and plain) before and after incubation with bovine serum albumin. Temperature-measurement experiments were conducted spanning both room temperature and a physiological temperature range of 10 K. The results highlight the model's effectiveness, especially for single-core particles exhibiting Brownian relaxation behavior, with temperature errors controlled to within ±0.4 K. The model's predictions remained consistent irrespective of particle chemical compositions, while detecting hydrodynamic diameter changes post-incubation, indirectly highlighting protein–corona interactions. These findings enhance the application potential of magnetic nanothermometry in hyperthermia therapy, contributing to preclinical validations and insights into nanoparticle–biological interactions. [ABSTRACT FROM AUTHOR]

Magnetic nanomaterials have played a crucial role in promoting the application of nanotechnology in the biomedical field. Although conventional magnetic nanomaterials such as iron oxide nanoparticles (NPs) are used as biosensors, drug delivery vehicles, diagnostic and treatment agents for several diseases, the persistent pursuit of high‐performance technologies has prompted researchers to continuously develop new types of magnetic nanomaterials such as iron carbide NPs. Considering their potential application in biomedicine, magnetic NPs responsive to exogenous or endogenous stimuli are developed, thereby enhancing their applicability in more complex versatile scenarios. In this review, the synthesis and surface modification of magnetic NPs are focused, particularly iron carbide NPs. Subsequently, exogenous and endogenous stimuli‐responsive magnetic NP‐based theranostic platforms are introduced, particularly focusing on nanozyme‐based technologies and magnetic NP‐mediated immunotherapy, which are emerging stimuli‐responsive treatments. Finally, the challenges and perspectives of magnetic NPs to accelerate future research in this field are discussed. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles are of great interest to scientists as potential drug carriers. Therefore, it is essential to analyze the processes these nanoparticles undergo at the cellular level. The present paper demonstrates the effect of a constant and rotating magnetic field on penetration of TEMPOL-functionalized magnetite nanoparticles into yeast cells. The interactions between nanoparticles and yeast cells without and with a magnetic field were studied using electron spin resonance spectroscopy (ESR). The results showed that the ESR method can monitor the effect of a magnetic field on the magnetite nanoparticle penetration rate into the cells. [ABSTRACT FROM AUTHOR]

Circulating tumor cells (CTCs) are a crucial biomarker for early cancer diagnosis and progress of cancer metastasis. However, the extremely rare CTCs with large amounts of background leukocytes seriously restricte the purity of enriched CTCs. Herein, genetically engineered cell membrane‐coated magnetic nanoparticles with following properties are constructed: I) The leukocyte membrane camouflaged nanoparticles, which could significantly reduce nonspecific binding of homologous leukocytes and achieve high‐purity isolation of CTCs, are prepared by simple one‐step extrusion and II) the cellular membrane stably expressing single‐chain variable fragment (scFv) of anti‐epidermal growth factor receptor (EGFR) antibody could ensure the recognition of EGFR‐positive CTCs. The binding affinity of the resulting nanoparticles toward extracellular EGFR protein improved more than 100‐fold compared with natural cell membrane‐coated nanoparticles. Furthermore, compared with commercial immunomagnetic nanoparticles, the functional nanoparticles achieved a greater capture efficiency in artificial blood samples and the cell purity increased from 64.8% to 93.5%. Consequently, the authors successfully isolate high pure CTCs from 6 out of 6 cancer patients using engineered cell membrane‐coated nanoparticles. This platform exhibits a promising potential for CTC detection in clinical samples, offering an innovative method for cancer diagnosis and prognosis evaluation. [ABSTRACT FROM AUTHOR]

Introduction: Neoadjuvant therapy constitutes a valuable modality for diminishing tumor volume prior to surgical resection. Nonetheless, its application encounters limitations in the context of recurrent tumors, which manifest resistance to conventional treatments. Silver nanoparticles (AgNPs) have emerged as a promising alternative for cancer treatment owing to their cytotoxic effects. Methods: Cellular viability was assessed by Alamar blue assay in 4T1 breast cancer cell line. Silver biodistribution was detected by an inductively coupled plasma optical emission spectrometer in an in vivo mice model. For neoadjuvant evaluation, mice were randomized and treated intratumoral with AgNPs-G or intraperitoneally with doxorubicin (DOX) as a control. Recurrence was determined after 170 days by counting lung metastatic nodules (dyed with Bouin solution) with histological confirmation by H&E. Masson's stain, Ki67 immunohistochemistry, and a TUNEL assay were performed in lungs from treated mice. Results: AgNPs-G reduced 4T1 cell viability and in an ex vivo assay the AgNPs-G decreased the tumor cell viability. After intravenous administration of AgNPs-G were detected in different organs. After intratumor administration, AgNPs-G are retained. The AgNPs-G treatment significantly reduced tumor volume before its surgical resection. AgNPs-G reduced the development of lung metastatic nodules and the expression of Ki67. TUNEL assay indicated that AgNPs-G didn't induce apoptosis. Conclusions: We concluded that intratumor administration of AgNPs-G reduced tumor volume before surgical resection, alongside a reduction in lung metastatic nodules, and Ki67 expression. These findings provide valuable insights into the AgNPs-G potential for intratumor and neoadjuvant cancer therapies. However, further research is needed to explore their full potential and optimize their use in clinical settings. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examines the application of magnetic nanoparticle hyperthermia (MNH), a cancer treatment technique that utilizes magnetic particles at the scale of nanometers and a controlled magnetic field to selectively heat and destroy cancer cells. The study focuses on a specific system, the Sarah Nanotechnology System, which combines these magnetic particles and a device that generates the magnetic field. The main goal is to ensure this treatment is safe for patients. We used a combination of real-world experiments and computer simulations to test how the system affects the body's temperature, particularly aiming to avoid overheating healthy tissues. We used a virtual human model to predict temperature changes during treatment. The findings are promising for safely using this advanced technology in cancer treatment, potentially offering a new, targeted approach for patients with advanced-stage tumors. This could be a significant step forward in cancer therapy, highlighting the importance of combining experimental and computational methods in medical research. The present study focuses on the development of a methodology for evaluating the safety of MNH systems, through the numerical prediction of the induced temperature rise in superficial skin layers due to eddy currents heating under an alternating magnetic field (AMF). The methodology is supported and validated through experimental measurements of the AMF's distribution, as well as temperature data from the torsos of six patients who participated in a clinical trial study. The simulations involved a computational model of the actual coil, a computational model of the cooling system used for the cooling of the patients during treatment, and a detailed human anatomical model from the Virtual Population family. The numerical predictions exhibit strong agreement with the experimental measurements, and the deviations are below the estimated combined uncertainties, confirming the accuracy of computational modeling. This study highlights the crucial role of simulations for translational medicine and paves the way for personalized treatment planning. [ABSTRACT FROM AUTHOR]

We present FexOy composite particles prepared by pulsed laser irradiation of α-Fe2O3 nanoparticles dispersed in ethyl acetate and irradiated using a laser beam in the ultraviolet range with a wavelength of 355 nm. The sizes of particles and composition were controlled by tuning the laser parameters, such as laser fluence and irradiation time. We showed the evolution of the composition through X-ray diffraction measurements. Reactive bond molecular dynamics simulation results show bond breaking/formation during the synthesizing process. We examined the magnetic properties of the particles and showed that coercivity can be changed by the composition of particles and by increasing or decreasing particle size. The choice of systems built of iron and iron oxides made it possible to introduce the exchange bias effect into a range of magnetic properties of synthesized particles. [ABSTRACT FROM AUTHOR]

Fe3O4 magnetic nanoparticles (MNPs) have attracted tremendous attention due to their superparamagnetic properties, large specific surface area, high biocompatibility, non–toxicity, large–scale production, and recyclability. More importantly, numerous hydroxyl groups (–OH) on the surface of Fe3O4 MNPs can provide coupling sites for various modifiers, forming versatile nanocomposites for applications in the energy, biomedicine, and environmental fields. With the development of science and technology, the potential of nanotechnology in the food industry has also gradually become prominent. However, the application of composite Fe3O4 MNPs in the food industry has not been systematically summarized. Herein, this article reviews composite Fe3O4 MNPs, including their properties, modifications, and physical functions, as well as their applications in the entire food industry from production to processing, storage, and detection. This review lays a solid foundation for promoting food innovation and improving food quality and safety. [ABSTRACT FROM AUTHOR]

In this study, a novel nanocarrier based on magnetic nanoparticles was synthesized via a facile method and modified by alginate. The synthesized nanocarrier was characterized using Fourier transform infrared spectroscopy, field emission scanning electron microscopy, thermogravimetric analysis, Brunauer–Emmett–Teller, vibrating sample magnetometer, and x-ray diffraction analysis. Different factors were optimized to evaluate the adsorption of imatinib on the nanoadsorbent. Imatinib was chosen as an anti-cancer drug, and the release rate of imatinib was investigated in simulated human blood (pH = 7.4) and simulated cancer (pH = 5.6) fluids. The drug adsorption isotherms, kinetics, and thermodynamics were studied. Based on the equilibrium adsorption results, the Langmuir isotherm and the pseudo-second-order kinetic models indicated a better fit than other models. Values of the enthalpy and entropy for drug sorption on the nanoadsorbent were positive. The negative value of Gibbs free energy reveals the spontaneous and feasible adsorption of imatinib on the nanoadsorbent. [ABSTRACT FROM AUTHOR]

Silica-coated magnetic-luminescent nanocomposites, obtained from Mn0.8Fe2.2O4 and near-white emitting GdVO4:Dy3+, reported in this work for possible application in combined imaging and magnetic fluid hyperthermia. Folic acid functionalization of the nanocomposite was further achieved for enhanced tumor affinity since folate receptors are overexpressed in cancer tissues. The nanocomposite showed the cubic-tetragonal biphasic structure corresponding to the cubic Fe3O4 and tetragonal GdVO4 phases. The compositions and surface modifications were confirmed by infrared spectroscopy. The formation of agglomerated nanoparticle was observed from the transmission electron microscopy comprising of particles in the 20-nm size range. Brilliant near white emission can be seen from the nanocomposites upon excitation at 287 nm. The induction heating analysis was performed at the alternating magnetic field strengths of 2.15 × 106 kAm−1 s−1, 3.05 × 106 kAm−1 s−1, and 4.58 × 106 kAm−1 s−1. The MTT assay revealed that the nanocomposite exhibits 50% cell viability towards MDA-231 breast cancer cell line. Thus, these magnetic-luminescent nanocomposites will have potential applications for magnetic fluid hyperthermia and optical imaging. [ABSTRACT FROM AUTHOR]

We present a novel method for estimating the magnetic field that can generate the desired magnetic force to move magnetic nanoparticles in a region of interest. The magnetic field is expanded using vector spherical harmonics, and the optimal multipole moments are estimated. The multipole moments are included in quadratic form because the magnetic force is defined as the product of the magnetic field and its gradient. We transform the system of quadratic equations into a rank-one-matrix estimation problem to construct a convex numerical algorithm based on a well-established proximal operation. The proposed method was validated using numerical simulations and can be used to design magnetic force patterns that cannot be generated using a simple coil pair. [ABSTRACT FROM AUTHOR]

[Display omitted] Macrophages are known to depict two major phenotypes: classically activated macrophages (M1), associated with high production of pro-inflammatory cytokines, and alternatively activated macrophages (M2), which present an anti-inflammatory function. A precise control over M1-M2 polarization is a promising strategy in therapeutics to modulate both tissue regeneration and tumor progression processes. However, this is not a simple task as macrophages behave differently depending on the microenvironment. In agreement with this, non-consistent data have been reported regarding macrophages response to magnetic iron oxide nanoparticles (MNPs). To investigate the impact of both tissue microenvironment and MNPs properties on the obtained macrophage responses, single-core (SC) and multi-core (MC) citrate coated MNPs, are synthesized and, afterwards, loaded with a macrophage polarization trigger, IL-4. The developed MNPs are then tested in macrophages subjected to different stimuli. We demonstrate that macrophages treated with low concentrations of MNPs behave differently depending on the polarization stage independently of the concentration of iron. Moreover, we find out that MNPs size and morphology determines the effect of the IL-4 loaded MNPs on M1 macrophages, since IL-4 loaded SC MNPs favor the polarization of M1 macrophages towards M2 phenotype, while IL-4 loaded MC MNPs further stimulate the secretion of pro-inflammatory cytokines. [ABSTRACT FROM AUTHOR]

Metal nanoparticles play a crucial role in the medical industry due to its desirable properties such as antimicrobial activity, anti‐cancer property, and its application in disease diagnostics. These properties enable the nanoparticles to be used as efficient medical devices for various treatments as well as drug delivery systems. Despite all the positives, metal nanoparticles are known for causing toxicity in the living system. The toxicological effects of metal nanoparticles are due to their size, surface*e coating, and the dose administered. Therefore, it is important to study the toxic effects of these nanoparticles before they are used as medical devices for various treatments. This review focuses on the five major metal nanoparticles used in the medical field, namely; silver, gold, iron oxide, zinc oxide, and titanium dioxide nanoparticles. The non‐exhaustive review consists of an introduction to the toxicological effects of these nanoparticles, the biocompatibility, and the current and future clinical perspective on metal nanoparticles. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles have gained attention as a potential structure for therapy and diagnosing oncological diseases. The key property of the magnetic nanoparticles is the ability to respond to an external magnetic field. It is known that magnetofection causes an increase in the cellular uptake of RNA and DNA in complexes with magnetic nanoparticles in the presence of a permanent magnetic field. However, the influence of a dynamic magnetic field on the internalization of MNPs is not clear. In this work, we propose the idea that applying external low-frequency dynamic magnetic fields may decrease the cellular uptake, such as macrophages and malignant neuroblastoma. Using fluorescence microscopy and atomic emission spectroscopy, we found that oscillating magnetic fields decreased the cellular uptake of magnetic nanoparticles compared to untreated cells by up to 46%. In SH-SY5Y tumor cells and macrophage RAW264.7 cells, the absolute values of Fe per cell differed by 0.10 pg/cell and 0.33 pg/cell between treated and untreated cells, respectively. These results can be applied in the control of the cellular uptake in different areas of biomedicine. [ABSTRACT FROM AUTHOR]

Nanomedicine is a promising approach for tumor therapy but penetration is challenged by complex tumor microenvironments. The purpose of this study is to design nanoparticles and analyze their transport in two abnormal microenvironments through a 2-D simulation. Employing a Computational Fluid Dynamics (CFD) approach, tumor vascular-interstitial models were initially simulated, and the impact of nanoparticles on the velocity profile and pressure gradient within the tumor microenvironment was observed. Through meticulous mesh analysis, it was determined that optimal outcomes were achieved using a quadrilateral meshing method for pancreatic tumor and a quad/tri meshing method for hepatic tumor. Results showed an increase in vessel diameter correlated with elevated blood flow velocity, reaching a maximum of 1.40 × 10^−3 m/s with an expanding cell gap. The simulation results for pressure distribution show that as vessel diameter increases, the velocity of nanoparticles in blood increases and decreases the pressure of blood. Intriguingly, distinct fluid flow patterns in pancreatic and hepatic tumors, emphasize how microenvironmental differences, specifically cell pore size, profoundly impact therapeutic agent transport, with implications for drug delivery strategies in cancer therapy. These simulation-based insights enable researchers to anticipate nanofluid behavior in realistic settings. Future work, incorporating immune cells, will enhance the understanding of nanoparticle efficiency in cancer therapy. [ABSTRACT FROM AUTHOR]

Herein was conducted a compelling structural analysis of magnetite nanoparticles (NPs) coated with dodecyl amine (DDA), compared with uncoated magnetite, both previously synthesized by an accelerated one-pot synthesis, starting from a single iron precursor. XRD/TEM results for the obtained nanomaterial Fe3O4@DDA showed the predominance of Fe3+ cations on the most stable atomic plane of magnetite (111). Using Molecular Dynamics calculations, with the observed atomic dispositions as inputs, it was established that NPs' surface and DDA might interact by short-distance coordination, with DDA as a ligand of Fe3+ cations, or by long-distance adsorption via H-bonding. The simulations align with TEM images, revealing an amorphous contour corresponding to the organic coating arranged as a bilayer. The TGA analysis corroborated a dual mass loss profile relating to the DDA bilayer at 116 °C and 350 °C. The Fe3O4@DDA NPs' magnetic properties (saturation magnetization (Ms) and coercivity field (Hc)) were preserved. Fe3O4@DDA exhibited a reduction of 3 emu/g in Ms and an increment of 12 Oe in Hc, compared with Fe3O4 NPs, attributable to the coating inhomogeneity and the consequent anisotropy rise. Fe3O4@DDA triggered concentration-dependent cytotoxic effects on the human hepatocarcinoma cell line HepG2. At 50 µg/mL after incubation of 48 h, cell viability was 63% < , whereas at 72 h only 30% of cells were viable. At 300 µg/mL, less than 10% of HepG2 cells remained viable after 24 h of incubation. In the case of Fe3O4 NPs assessed in the same cell line, cell viability remained as high as 80% at 300 µg/mL during 72 h of incubation. Trypan blue assay suggests membrane integrity damage as the primary mechanism of HepG2 cell death. Even though the in vitro results herein presented are preliminary, they represent the first report of the cytotoxic effect of magnetite coated with a nitrogenous surfactant. [ABSTRACT FROM AUTHOR]

Magnetite nanoparticles (Fe3O4) were prepared by chemical coprecipitation method using ferric chloride (FeCl3) and heptahydrate ferrous sulfate (FeSO4·7H2O) salts employing sodium hydroxide (NaOH) as a precipitant. To determine the size, shape, and chemical makeup of the produced magnetite nanoparticles, the generated powders were examined by transmission electron microscope, scanning electron microscope, atomic force microscope, and X-ray diffractometer. It was found that the magnetite powder had made a face-centered cubic crystal structure and spherical-like particle form with particle diameters of about 30 nm. The magnetic properties of magnetite nanoparticles were evaluated using a vibrating sample magnetometer. The obtained superparamagnetic properties of the produced nanoparticles, with saturation magnetization and coercivity of 50.75 emu/g and 30.09 Oe, respectively, allow them for applications in drug delivery, MRI contrast agent, catalysis, degradation of antibiotics, antibacterial activity, removal of heavy metals and organic dyes, etc. [ABSTRACT FROM AUTHOR]

Magnetic–plasmonic nanoparticles (NPs) have attracted great interest in many fields because they can exhibit more physical and chemical properties than individual magnetic or plasmonic NPs. In this work, we synthesized Au- or Ag-decorated Fe3O4 nanoparticles coated with PEI (Fe3O4-PEI-M (M = Au or Ag) NPs) using a simple method. The influences of the plasmonic metal NPs' (Au or Ag) coating density on the magnetic and plasmonic properties of the Fe3O4-PEI-M (M = Au or Ag) NPs were investigated, and the density of the plasmonic metal NPs coated on the Fe3O4 NPs surfaces could be adjusted by controlling the polyethyleneimine (PEI) concentration. It showed that the Fe3O4-PEI-M (M = Au or Ag) NPs exhibited both magnetic and plasmonic properties. When the PEI concentration increased from 5 to 35 mg/mL, the coating density of the Au or Ag NPs on the Fe3O4 NPs surfaces increased, the corresponding magnetic intensity became weaker, and the plasmonic intensity was stronger. At the same time, the plasmonic resonance peak of the Fe3O4-PEI-M (M = Au or Ag) NPs was red shifted. Therefore, there was an optimal coverage of the plasmonic metal NPs on the Fe3O4 NPs surfaces to balance the magnetic and plasmonic properties when the PEI concentration was between 15 and 25 mg/mL. This result can guide the application of the Fe3O4-M (M = Au or Ag) NPs in the biomedical field. [ABSTRACT FROM AUTHOR]

Cancer is still the leading cause of death in the world despite the developing research and treatment opportunities. Failure of these treatments is generally associated with cancer stem cells (CSCs), which cause metastasis and are defined by their resistance to radio- and chemotherapy. Although known stem cell isolation methods are not sufficient for CSC isolation, they also bring a burden in terms of cost. The aim of this study is to develop a high-efficiency, low-cost, specific method for cancer stem cell isolation with magnetic functional nanoparticles. This study, unlike the stem cell isolation techniques (MACS, FACS) used today, was aimed to isolate cancer stem cells (separation of CD133+ cells) with nanoparticles with specific affinity and modification properties. For this purpose, affinity-based magnetic nanoparticles were synthesized and characterized by providing surface activity and chemical reactivity, as well as making surface modifications necessary for both lectin affinity and metal affinity interactions. In the other part of the study, synthesized and characterized functional polymeric magnetic nanoparticles were used for the isolation of CSC from the human osteosarcoma cancer cell line (SAOS-2) with a cancer stem cell subpopulation bearing the CD133 surface marker. The success and efficiency of separation after stem cell isolation were evaluated via the MACS and FACS methods. As a result, when the His-graft-mg-p(HEMA) nanoparticle was used at a concentration of 0.1 µg/mL for 106 and 108 cells, superior separation efficiency to commercial microbeads was obtained. [ABSTRACT FROM AUTHOR]

Four samples containing magnetic iron oxide nanoparticles (MIONs) of various sizes are prepared employing a simple low-temperature method of oxidative precipitation from FeCl2∙4H2O–NaOH–NaNO3 aqueous solution. For the preparation of two samples, the usual oxidation-precipitation synthesis protocol is modified by using ethylenediaminetetraacetic acid (EDTA) chelating agent as a stabilizer of the Fe2+ ions in a solution, which results in the partial capping of the prepared MIONs with EDTA molecules. Three out of four samples are subjected to citric acid (CA) functionalization in the post synthesis protocol. Structural and magnetic properties of the synthesized MIONs are assessed using various experimental techniques (XRD, TEM, Fourier transform infrared, dynamic light scattering, Mössbauer, and SQUID). The average size of spherical-like MIONs is tuned from 7 nm to 38 nm by changing the synthesis protocol. Their room temperature saturation magnetization, M s, is in the range of 43 to 91 emu g−1. Magnetic heating ability, expressed via specific absorption rate value, which ranges from 139 to 390 W/gFe, is discussed in relation to their structural and magnetic properties and the possible energy dissipation mechanisms involved. The best heating performance is exhibited by the sample decorated with EDTA and with a bimodal size distribution with average particle sizes of 14 and 37 nm and M s = 87 emu g−1. Though this sample contains particles prone to form aggregates, capping with EDTA provides good colloidal stability of this sample, thus preserving the magnetic heating ability. It is demonstrated that two samples, consisting of 7 nm-sized CA- or 14 nm-sized EDTA/CA-functionalized superparamagnetic MIONs, with a similar hydrodynamic radius, heat in a very similar way in the relatively fast oscillating alternating current magnetic field, f = 577 kHz. [ABSTRACT FROM AUTHOR]

The magnetite Fe3O4 nanoparticles have a broad range of applications due to the combination of specific magnetic and electrical properties. It is important to develop synthesis approaches where magnetite nanoparticles can be obtained from cheap precursors in large quantities rapidly. Herein, we report a straightforward process for synthesizing magnetite from Fe(III) chloride precursor. NaBH4-assisted precipitation of ferric chloride provides stoichiometric Fe3O4 nanoparticles within 1 minute. The obtained particles exhibit superparamagnetic behavior with saturation magnetization of as high as 55.4 emu/g. The simple addition of surfactant cetrimonium bromide to the synthesis mixture allows to reduce crystallite sizes and enhance the magnetic properties even further. [ABSTRACT FROM AUTHOR]

In this study, the characterization and magnetic properties of CoFe2O4 nanoparticles synthesized by co‐precipitation method were investigated. The calcined products obtained were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐ray (EDAX), Fourier transformed infrared (FTIR) spectroscopy, and vibrating sample magnetometer. Crystallite size and phase composition were analyzed by X‐ray diffraction. Crystallite size and phase composition were analyzed by X‐ray diffraction. The average crystallite size of CoFe2O4 nanoparticles increased in the range of 15.85–32.14 nm with an increase in temperature from 500 to 700°C. It was observed that spherical CoFe2O4 nanoparticles were produced. Synthesis of CoFe2O4 nanoparticles was confirmed using XRD, SEM‐EDAX, and FTIR analyses. The effect of crystallite size, calcination temperature, and lattice parameter on saturation magnetization, remanent magnetization, coercivity, and magnetocrystalline anisotropy were investigated by vibrating sample magnetometer. As the crystallite size value increased, magnetocrystalline anisotropy also increased. [ABSTRACT FROM AUTHOR]

There has been few research on the affect and distribution of different shapes of nanoparticles inside an organism during extraction and drug targeting. In order to obtain the distribution of magnetic nanoparticles with different morphology and size in vivo, a general method of Re-188 labeled Magnetic Core–Shell Nanoparticles (MNPs) Materials was developed. Based on the prepared magnetic particles with three different morphologies and sizes, including 230 nm spherical Fe3O4@SiO2 particles (S-230), 100 nm spherical Fe3O4@SiO2 particles (S-100) and peanut shaped Fe3O4@SiO2 particles (P-180, the length of the short axis is about 100 nm and the length of the long axis is about 180 nm), the aminated MNPs were labeled with radionuclide Re-188 through the coupling of diethylenetriamine pentaacetic anhydride. The nuclide Re-188 was labeled to investigate their distribution behavior in mice. Most of the small-size particles S-100 can be separated from the capture of the endothelial reticular system and removed by renal metabolism. Most of the larger particles, S-230 and P-180, will be captured by the endothelial reticular system, and the nanoparticles P-180 with large aspect ratio are easier to be captured by the tissue in the spleen and enter the cells through endocytosis. [ABSTRACT FROM AUTHOR]

This study was conducted to synthesize magnetic wood through the ex situ impregnation method of magnetite nanoparticles and analyze its physical properties and characterization. The process was initiated with the synthesis of magnetite nanoparticles by the co-precipitation method and the nano-magnetite was successfully synthesized with a particle distribution of 17–233 nm at an average size of 75 nm. Furthermore, the impregnation solution consisted of three different levels of magnetite nanoparticles dispersed in furfuryl alcohol, untreated and furfurylated wood for comparison. Sengon wood (Falcataria moluccana Miq.) was also used due to its low physical properties. The impregnation process was conducted by immersing the samples in the solution at a vacuum of −0.5 bar for 30 min, followed by a pressure of 1 bar for 2 h. There was also an improvement in the physical properties, such as weight percent gain, bulking effect, anti-swelling efficiency and density, while the water uptake continued to decrease. Additionally, magnetite nanoparticles appeared in wood microstructure image, supported by the result of ferrum content in chemical element analysis. The results showed that chemical change analysis proved the presence of Fe–O functional group cross-linked with wood polymer. The diffractogram also reported the appearance of magnetite nanoparticles peak and a decrease in crystallinity due to an increase in the concentration. Based on the analysis, sengon wood was classified as a superparamagnetic material with soft magnetic characteristics and the optimum treatment was furfurylated-magnetite 12.5% wood. [ABSTRACT FROM AUTHOR]

The article utilizes the fractional bioheat model in spherical coordinates to explain the transfer of heat in living tissues during magnetic hyperthermia treatment for tumors. Maintaining therapeutic temperature is crucial in magnetic fluid hyperthermia, which requires accurate estimations of power dissipation to determine the appropriate number of magnetic particles required for treatment. To address this problem, a hybrid numerical approach that combines Laplace transforms, change of variables, and modified discretization techniques is proposed in this paper. The study investigates the impact of the fractional parameter and differences in thermophysical properties between diseased and healthy tissue. The numerical temperature results are presented in a graph, and their validity is demonstrated by comparing them with previous literature. [ABSTRACT FROM AUTHOR]

In the separation and determination of trace amounts of drugs in aqueous samples, there is a major challenge in synthesizing highly efficient, cost‐effective, and easy‐to‐use adsorbents based on natural polymers, which are also biocompatible and biodegradable. In the proposed method, magnetite nanoparticles (Fe3O4) on chitosan (as the carrier) modified with β‐cyclodextrin (BCD) were used as a suitable adsorbent for the pre‐concentration and solid‐phase extraction of trace amounts of Amitriptyline HCl (hydrochloride). Ultraviolet spectrophotometer (λ = 236 nm) was the main instrument used for analyte detection and quantification. Moreover, X‐ray diffraction, Fourier transform infrared spectroscopy, Field Emission Scanning Electron Microscopy, and Energy‐Dispersive X‐ray were used for the identification and characterization of the structure and morphology of the adsorbent and to establish the formation of the synthesized magnetic nanosorbents, as well as to confirm the analyte binding to the adsorbent. Experimental variables affecting the extraction/pre‐concentration and determination of the analyte were investigated and optimized; pH of the sample solution, the amount of NaCl salt (in terms of ionic strength of the solution), the amount of adsorbent, temperature, adsorption time, and volume of the eluent (methanol) were the optimized parameters. Finally, the method was successfully applied for the determination of spiked Amitriptyline hydrochloride (HCl) in tap water and human urine samples. Also, High‐Performance Liquid Chromatography was performed on the aqueous samples to compare the proposed method with the USP (the United States Pharmacopeia) standard method of Amitriptyline HCl assay and after performing a t‐test (confidence level of 95%), no significant difference was observed between the two methods. High accuracy and precision (RSD = 3.91%), High analysis speed, few limitations, low expenses, pure extracted analyte, and low waste were the advantages of this method. This method was also compatible with many existing device methods. Under the optimized experimental conditions, the calibration graph was linear in the range of 0.183 to 50 mg.L−1 with a correlation coefficient of 0.996. RSD of the method was 3.91%, the limit of detection was 37.8 µg.L−1, the maximum sorption capacity of the adsorbent for Amitriptyline hydrochloride was 306.525 mg.g−1 and the preconcentration factor was 3.61. Eventually, the proposed method was compared to other methods that have been performed for the determination of Amitriptyline hydrochloride. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) have been widely investigated as effective drug carriers for targeted tumor therapy. However, the successful application of this technology in the human body requires reliable imaging support. Magnetoacoustic Concentration Tomography of Magnetic Nanoparticles with Magnetic Induction (MACT-MI) is an electromagnetic-ultrasonic coupling imaging technique that holds great promise in improving imaging resolution and providing unique advantages for tumor monitoring and treatment. To evaluate the imaging feasibility of MACT-MI technology for targeted therapy of breast tumors, this study establishes a realistic breast model and takes into account the distribution of magnetic particles within the actual breast tissue environment. A concentration gradient model is introduced, and the finite element method is employed to solve the electromagnetic and sound fields. In addressing the research objective, the forward problem is investigated by analyzing the magnetic force and sound pressure distribution for various tumor sizes and locations, different breast tissues, and both benign and malignant tumors. The results obtained indicate that the magnetoacoustic signal emitted by magnetic particles facilitates accurate mapping of the size and location information of magnetic particles enveloping breast tumors, as well as distinguishing between benign and malignant tumors. [ABSTRACT FROM AUTHOR]

The aim of the present work was to examine the effect of polyethylene glycol (PEG)-coated superparamagnetic iron oxide (SPIO) nanoparticles carrying Pik3cb short hairpin RNA (shRNA) in the prevention of restenosis with the aid of ultrasound and a magnetic field. SPIO is a type of contrast agent used in medical imaging to enhance the visibility of specific tissues or organs. It consists of tiny iron oxide nanoparticles that can be targeted to specific areas of interest in the body. PEG-coated SPIO nanoparticles carrying Pik3cb shRNA (SPIO-shPik3cb) were prepared, and the particle size and zeta potential of PEG-coated SPIO nanoparticles with and without Pik3cb shRNA were examined. After a right common artery balloon-injured rat model was established, the rats were randomly divided into four groups, and the injured arteries were transfected with SPIO-shPik3cb, saline, SPIO-shcontrol and naked shRNA Pik3cb. During the treatment, each group was placed under a magnetic field and was transfected with the aid of ultrasound. Rats were sacrificed, and the tissue was harvested for analysis after 14 days. The results suggested that the mean particle size and zeta potential of SPIO-shPik3cbs were 151.45 ± 11 nm and 10 mV, respectively. SPIO-shPik3cb showed higher transfection efficiency and significantly inhibited the intimal thickening compared with naked Pik3cb shRNA in vascular smooth muscle cells (VSMCs) (* P  < 0.05). Moreover, SPIO-shPik3cb could also significantly downregulate the expression of pAkt protein compared with naked Pik3cb shRNA. According to the results, SPIO-shPik3cb can remarkably inhibit the intimal thickening under a combination of magnetic field exposure and ultrasound. [ABSTRACT FROM AUTHOR]

Silica-coated Iron oxide (Fe3O4@SiO2-NP) and silica (SiO2-NP) nanoparticles were prepared and derivatized with a Eu(III) complex to yield magneto-fluorescent (Fe3O4@SiO2-NP:C2) and fluorescent (SiO2-NP:C2) nanomaterials that could work as possible biosensors. The Fe3O4-NP core is inactive, although it contains an important property, magnetism, allowing particles to be directed to where they are needed. The Fe3O4@SiO2-NP:C2 and SiO2-NP:C2 (without magnetism) acted as fluorescent probes by means of an anchored europium (Eu) complex, which was used as fluorescence promoter, holding condensed aromatic ring as neutral ligands working as antenna – phenanthroline – that enhanced the fluorescence. The results showed that the cytotoxicity of the samples was almost inexistent, while fluorescent character was maintained unaltered in cellular medium for all the studied materials. This work provides new understandings through these nanomaterials for their potential application in imaging, representing a less toxic, more economically viable and sustainable solution, compared to existing ones. [ABSTRACT FROM AUTHOR]