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Understanding the internal magnetization structure of an individual ferromagnetic nanoparticle (MNP) is crucial for deciphering its magnetic characteristics. Unfortunately, while certain techniques can measure the magnetic properties of an individual MNP, they fall short of accurately detecting the internal magnetization structure. In this work, micromagnetic simulations were employed to construct the internal magnetization structure of an individual CoFe2O4 (CFO) nanopyramid, and the energy jump behavior during the magnetization process was successfully explained, with simulation results aligning with dynamic cantilever magnetometry (DCM) experimental outcomes. Subsequently, the external stray field of the nanopyramid was simulated, and the stray field gradient map revealed distinct bright and dark regions corresponding to the reverse and forward saturation magnetizations of the CFO nanopyramid. This result is possible to be verified by magnetic force microscopy (MFM) measurements of individual CFO nanopyramids. The confidence in the accuracy of the simulated internal magnetization structure was significantly enhanced by independently verifying the micromagnetic simulation results through DCM and MFM experiments. Our work proposes a convenient and cost-effective method for studying the internal magnetization structure of individual MNPs. [ABSTRACT FROM AUTHOR]

We report the experimental characterization and finite element modeling of magnetic fluid hyperthermia (MFH) in tissue-like media using tetramethyl ammonium hydroxide coated superparamagnetic iron oxide magnetic nanoparticles (MNPs) of size ∼19.6 ± 1.2 nm, prepared using a co-precipitation technique. MFH properties are probed for the MNPs in ∼1 wt. % agar, resembling the tumor and surrounding normal tissues. The field-induced temperature rise (ΔT) is experimentally measured in real-time utilizing an infrared camera. A finite element model (FEM) is utilized to simulate the spatiotemporal variations in the thermal profiles, which are found to be in good agreement with the experimental data. FEM-based parametric studies reveal that the thermal conductivity of the medium is the most significant parameter influencing the thermal profiles. The spatiotemporal variations in the thermal profiles are numerically studied for seven different tissues, and the obtained results indicate the highest ΔT for the breast tissue in the tumor and the surrounding regions, which is due to the lowest volumetric specific heat and the highest thermal conductivity of the breast tissue, respectively. Numerical studies on the thermal profiles for sub-surface tumors with parametrically varying depths indicate a strong exponential correlation between the surface and tumor temperature, where the regression coefficients are found to be correlated with the thermo-physical properties of the tissues. The obtained findings are beneficial for developing a simplistic and easily deployable framework for a priori generation of the thermal profiles for various tissues during MFH, which is useful for appropriate planning and parameter selection for MFH-based therapy. [ABSTRACT FROM AUTHOR]

Cancer is a global issue and hence various efforts are being made. Iron oxide is considered a significant biochemical agent in the biomedical arena for cancer treatment. Marine macroalgae-mediated iron oxides especially, magnetite (Fe3O4) nanoparticles (NPs) are a prospective alternative to diagnose and treat cancer owing to their fluorescent and magnetic properties. We intend to appraise the usability of the aqueous extract of Rosenvingea intricata (R. intricata) in Fe3O4 NPs synthesis and to study their cytotoxic effects against human hepatocarcinoma (Hep3B) and pancreatic (PANC1) cancer cells. In the present study, R. intricata were collected from the coastal region of South Andaman, India. Aqueous extracts of R. intricata were utilized to synthesize Fe3O4 NPs via the co-precipitation method. Phycosynthesized Fe3O4 NPs exhibited wide peak at 400–600 nm from ultraviolet–visible diffused reflectance spectroscopic analysis which validated the formation of NPs. Band edge emission peak at 660 nm in fluorescent spectra confirmed the quantum confinement in Fe3O4 NPs. Fourier transform infrared spectroscopy confirmed the role of R. intricata as a capping and reducing agent with functional groups such as O–H, C–H, C=O, N=O, C=C, C–O, C–N, and C–S arising from amino acids, polysaccharides, aliphatic hydrocarbons, esters, amides, lignins, alkanes, aliphatic amines, and sulfates. Physicochemical properties such as crystallite size (14.36 nm), hydrodynamic size (84.6 nm), irregular morphology, elemental composition, particle size (125 nm), crystallinity, and saturation magnetization (0.90007 emu/g) were obtained from x-ray diffractometer, dynamic light scattering, scanning electron microscopy, energy dispersive x-ray spectrometer, high-resolution transmission electron microscopy, selected area electron diffraction and vibrating sample magnetometer techniques, respectively. The cell viability showed dose-dependent cytotoxic effects and enhanced the apoptosis against Hep3B and PANC1 cancer cells. R. intricata extract capped Fe3O4 NPs could be the most appropriate and effective nanomaterial for cancer treatment and management. [ABSTRACT FROM AUTHOR]

Halloysite nanotubes (HNTs) have a layered structure of clay silicate minerals and a tubular shape, which is suitable for the uniform loading of small substrates and drug molecules. The inner diameter of HNTs with an acidic solvent is selectively etched to increase the loading capacity of magnetic iron–platinum (FePt) nanoparticles. The FePt nanoparticles and etched HNTs (eHNT) are then composited by vacuum decompression. The resulting product is named FePt@eHNT and is used as a contrast agent for T2‐weighted magnetic resonance imaging. According to a comprehensive analysis of the material and its magnetic properties, by adding different proportions of HNTs before and after modification, the saturation magnetization can reach 23.769 emu g−1, which is higher than that of the composite materials studied in previous studies. This is because the tubular structure promotes the orderly displacement of the FePt nanoparticles under three‐dimensional space constraints and the uniform effect of the magnetic field. In addition, the magnetothermal effect of the composite material is observed and its potential as an imaging agent is investigated. In this study, the enhancement of its ferromagnetism and its potential to become a multifunctional composite material for applications in drug delivery, magnetic hyperthermia, and bioimaging is demonstrated. [ABSTRACT FROM AUTHOR]

AbstractThe need of the hour with respect to cancer treatment is a targeted approach with minimal or nil ramifications. Apropos, magnetic fluid hyperthermia (MFH) is emerging as a potential therapeutic strategy with anticipated reduced side effects for solid tumors. MFH causes cytotoxicity due to the heat generated owing to Hysteresis, Neel, and Brownian relaxation losses once magnetic nanoparticles (MNPs) carrying cancer cells are placed under an alternating magnetic field. With respect to MFH, iron oxide-based MNPs have been most extensively studied to date compared to other metal oxides with magnetic properties. The effectiveness of MFH relies on the composition, coating, size, physical and biocompatible properties of the MNPs. Pure iron oxide and doped iron oxide MNPs have been utilized to study their effects on cancer cell killing through MFH. This review evaluates the biocompatibility of pure and doped iron oxide MNPs and their subsequent hyperthermic effect for effectively killing cancer cells in vitro and in vivo. [ABSTRACT FROM AUTHOR]

This paper presents mathematical responses for the dual-phase-lag (DPL) hypothesis, which accounts for nonequilibrium heat transfer during magnetic nanoparticle hyperthermia in tumor. To get this precision, volume averaging is used for the local instantaneous energy formulation for tissues and blood. This study proposes a hybrid numerical strategy to solve this problem by combining change of variables, improved discretization techniques, and Laplace transforms. Using the Arrhenius formulas, the range of denatured proteins is used to assess the degree of heat damages to the tumor and healthy tissues. The impacts of porosity, the blood perfusion and metabolism on the temperature and the thermal injuries are studied. The numerical estimations of temperature and the resulting of thermal injuries are shown on a graph, and a comparison with earlier research establishes the results’ validity. [ABSTRACT FROM AUTHOR]

Background: Magnetic fluid hyperthermia (MFH) represents a promising therapeutic strategy in cancer utilizing the heating capabilities of magnetic nanoparticles when exposed to an alternating magnetic field (AMF). Because the efficacy and safety of MFH treatments depends on numerous intrinsic and extrinsic factors, therefore, the proper MFH setups should focus on thermal energy dosed into the cancer cells. Methods: In this study, we performed MFH experiments using human lung cancer A549 cells (in vitro) and NUDE Balb/c mice bearing human lung (A549) cancer (in vivo). In these two experimental models, the heat was induced by magnesium-doped iron(III) oxide nanoparticles coated with mPEG-silane (Mg0.1-γ-Fe2O3(mPEG-silane)0.5) when exposed to an AMF. Results: We observed that the lung cancer cells treated with Mg0.1-γ-Fe2O3(mPEG-silane)0.5 (0.25 mg·mL−1) and magnetized for 30 min at 14.4 kA·m−1 yielded a satisfactory outcome in reducing the cell viability up to ca. 21% (in vitro). The activation energy calculated for this field strength was estimated for 349 kJ·mol−1. Both volumetric measurements and tumor mass assessments confirmed by magnetic resonance imaging (MRI) showed a superior thermal effect in mice bearing human lung cancer injected intratumorally with Mg0.1-γ-Fe2O3(mPEG-silane)0.5 nanoparticles (3 mg·mL−1) and subjected to an AMF (18.3 kA·m−1) for 30 min four times at weekly intervals. Research demonstrated that mice undergoing MFH exhibited a marked suppression of tumor growth (V = 169 ± 94 mm3; p < 0.05) in comparison to the control group of untreated mice. The CEM43 (cumulative number of equivalent minutes at 43 °C) value for these treatments were estimated for ca. 9.6 min with the specific absorption rate (SAR) level ranging from 100 to 150 W·g−1. Conclusions: The as-obtained results, both cytotoxic and those related to energy calculations and SAR, may contribute to the advancement of thermal therapies, concurrently indicating that the proposed magnetic fluid hyperthermia holds a great potential for further testing in the context of medical applications. [ABSTRACT FROM AUTHOR]

Vascular cell overgrowth and lumen size reduction in pulmonary vein stenosis (PVS) can result in elevated PV pressure, pulmonary hypertension, cardiac failure, and death. Administration of chemotherapies such as rapamycin have shown promise by inhibiting the vascular cell proliferation; yet clinical success is limited due to complications such as restenosis and off‐target effects. The lack of in vitro models to recapitulate the complex pathophysiology of PVS has hindered the identification of disease mechanisms and therapies. This study integrated 3D bioprinting, functional nanoparticles, and perfusion bioreactors to develop a novel in vitro model of PVS. Bioprinted bifurcated PV constructs are seeded with endothelial cells (ECs) and perfused, demonstrating the formation of a uniform and viable endothelium. Computational modeling identified the bifurcation point at high risk of EC overgrowth. Application of an external magnetic field enabled targeting of the rapamycin‐loaded superparamagnetic iron oxide nanoparticles at the bifurcation site, leading to a significant reduction in EC proliferation with no adverse side effects. These results establish a 3D bioprinted in vitro model to study PV homeostasis and diseases, offering the potential for increased throughput, tunability, and patient specificity, to test new or more effective therapies for PVS and other vascular diseases. [ABSTRACT FROM AUTHOR]

AbstractThis study investigates the flow of an incompressible electroosmotic hybrid nanofluid through a micro-channel. The hybrid nanofluid consists of paramagnetic (Ta) and ferrimagnetic (Fe3O4) nanoparticles suspended in ethylene glycol. The Darcy model is applied to the porous media in the momentum equation, and its effects are also considered in the temperature equation, accounting for frictional and Joule heating effects. The micro-channel is influenced by both pressure and magnetic flux. The study derives an exact solution for the proposed model and evaluates key engineering parameters, such as the heat transfer rate. The findings show that a higher particle volume fraction reduces the velocity distribution, while an increased Darcy parameter decreases the rate of heat transfer. Additionally, the heat transfer rate diminishes with increasing Darcy parameter and electric flux. Notably, the ferrimagnetic nanofluid exhibits better thermal conductivity than the paramagnetic nanofluid. [ABSTRACT FROM AUTHOR]

Emerging as a revolutionary strategy to fabricate dynamic three dimesional (3D) structures, 4D printing (4DP) mainly refers to printed materials capable of changing form over time when exposed to a predetermined stimulus. Nevertheless, the 4D concept can be extended beyond shape‐morphing, by including also changes in the properties and/or functionalities of printed materials over time. To this end, this work explores the 4DP of multifunctional nanocomposites that can adapt to different application scenarios exploiting the stimuli‐activable properties of two functional nanofillers embedded into the polymeric matrix. In particular, a photocurable system loaded with both Fe3O4 nanoparticles (NPs) and AgNO3, as precursors for the in situ photo‐induced generation of Ag NPs, is used for the digital light processing of magnetic nanocomposites with integrated electrical and antibacterial functions. The composition of formulations is designed to both optimize their printability and maximize the magneto‐responsiveness and the electrical conductivity and/or antibacterial activity of the printed objects, given by Fe3O4 and Ag NPs, respectively. Finally, it is shown that the functional responses of the nanocomposites can be activated individually or in combination, which may be of particular interest for the fabrication of smart multifunctional devices with potential applications ranging from soft electronics to biomedicine. [ABSTRACT FROM AUTHOR]

Hyperthermia therapy refers to the elevating of a region in the body for therapeutic purposes. Different techniques have been applied for hyperthermia therapy including laser, microwave, radiofrequency, ultrasonic, and magnetic nanoparticles and the latter have received great attention in recent years. Magnetic hyperthermia in cancer therapy aims to increase the temperature of the body tissue by locally delivering heat from the magnetic nanoparticles to cancer cells with the aid of an external alternating magnetic field to kill the cancerous cells or prevent their further growth. This review introduces magnetic hyperthermia with magnetic nanoparticles. It includes the mechanism of the operation and magnetism behind the magnetic hyperthermia phenomenon. Different synthesis methods and surface modification to enhance the biocompatibility, water solubility, and stability of the nanoparticles in physiological environments have been discussed. Recent research on versatile types of magnetic nanoparticles with their ability to increase the local temperature has been addressed. [ABSTRACT FROM AUTHOR]

One of the most effective parameters in the thermal treatment of liver cancer by microwave heating method is the changes in the input power to the antenna. This study aims to numerically investigate the effects of the change in the input power to the microwave antenna in the presence of magnetic nanoparticles using the finite element method in liver tumors. Also, the importance of the type of nanoparticles, treatment time and side effects were investigated. According to the results, after the injection of maghemite nanoparticles, the purification time is 7.35 s at a power of 10 W and reaches 6.1 s when the power is increased to 100 W. Also, the ratio of the destroyed healthy volume of the tissue to the tumor volume is less than 20% in the mentioned powers, and the treatment can be considered independent of the power. After the injection of magnetite and FccFePt nanoparticles at a power of 10 W, the treatment time was calculated as 176 s and 295 s, respectively, and with the increase of the input power, the reduction of the treatment time was observed. So that the treatment time was reduced to 58 s and 74 s, respectively, at 100 W. In terms of side effects, for the mentioned nanoparticles, 4.89 and 8.93 times the volume of the tumor with a power of 10 W and when the power reaches 100 W, 4.05 and 5.6 times the volume of the tumor is destroyed from the healthy tissue, respectively. However, the lowest amount of healthy tissue destruction in these two nanofluids occurs at moderate powers—60 W and 50 W, respectively—so the dependence of treatment time and side effects on input power was observed. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles have been widely used in various fields of study. Due to the increasing use of these nanoparticles, it is important to develop sensitive methods for measuring these nanoparticles in real samples. In this research, a method was developed to measure magnetite nanoparticles using microfluidics science and paired emitter-detector diode-based photometry. The basis work of the designed system is based on the magnetic preconcentration of nanoparticles inside the microchip, dissolution by acid, and creation of a signal through the formation of an iron-thiocyanate complex. The validation results of the method showed that the linear range of the method is from 1.0 to 6.0 ppm with appropriate accuracy (recovery percentages: 104.0% and 95.6%) and precision (coefficient of variation: 0.17% and 0.15%), which is satisfactory for measuring trace amounts of magnetic nanoparticles. The limits of detection and quantification were obtained as 0.3 and 0.9 ppm, respectively. Compared to previously reported methods, the developed method provides higher sensitivity and simpler instrumentation of lower analysis cost by the use of a microfluidic chip for magnetic preconcentration of magnetic nanoparticles, washing, dissolution, and photometric determination. [ABSTRACT FROM AUTHOR]

The effects of modified γ-Fe2O3 magnetic nanoparticles having various sizes at different mass fractions on the stability of heavy oil-in-water emulsions were compared. The zeta potential, wettability, oil-water interfacial tension, apparent viscosity, and oil droplet distribution of the emulsions were measured. The optimal size of the γ-Fe2O3(-COOH) magnetic nanoparticles was 2–3 μm, and this resulted in the lowest water-separation rate (23.72% at 4 hours), greatest electrostatic repulsion, weakest hydrophilic effect, lowest interfacial tension, greatest migration resistance, and smallest and most uniform oil droplet distribution. In addition, the stability of the emulsions increased and then decreased as the mass fraction of γ-Fe2O3 (-COOH) magnetic nanoparticles increased because of the increased electrostatic repulsion and decreased migration resistance. This in-depth analysis of the effect of modified magnetic nanoparticle size on the stability of oil-in-water emulsions provides comprehensive theoretical support for achieving viscosity and resistance reduction in an environmentally friendly manner. [ABSTRACT FROM AUTHOR]

Hysteresis loss (P) of magnetic nanoparticles (MNPs) under alternating current excitation has been used to induce hyperthermia in cancer cells. We theoretically optimized the excitation field amplitude Hac and frequency f required to maximize P, while the product C = Hacf did not exceed a threshold value to avoid side effects in biomedical applications. We obtained analytical expressions for the optimum values of Hac and f as functions of C and MNP parameters. Almost the same P could be obtained for MNPs with magnetic core diameters dc ranging over 20–40 nm if Hac and f were optimized according to the dc value. A numerical example was a P of ∼0.4 kW/g Fe for immobilized MNPs under C = 2 × 109 A/(ms). We also examined the dependences of P on MNP parameters under the optimum excitation field. A large saturation magnetization was essential for a large P. The degradation of P caused by the dc distribution in a practical (realistic) sample was examined, and the conditions that reduce degradation were determined. There was a strong agreement among these properties between the analyses and numerical simulations. Finally, we showed how much P increased for suspended MNPs relative to that for immobilized MNPs. Overall, these results will be useful for the development of high-performance hyperthermia systems. [ABSTRACT FROM AUTHOR]

Protein-based nanoparticles have garnered significant attention in theranostic applications due to their superior biocompatibility, exceptional biodegradability and ease of functionality. Compared to other nanocarriers, protein-based nanoparticles offer additional advantages, including biofunctionality and precise molecular recognition abilities, which make them highly effective in navigating complex biological environments. Moreover, proteins can serve as powerful tools with self-assembling structures and reagents that enhance cell penetration. And their derivation from abundant renewable sources and ability to degrade into harmless amino acids further enhance their suitability for biomedical applications. However, protein-based nanoparticles have so far not realized their full potential. In this review, we summarize recent advances in the use of protein nanoparticles in tumor diagnosis and treatment and outline typical methods for preparing protein nanoparticles. The review of protein nanoparticles may provide useful new insights into the development of biomaterial fabrication. [Display omitted] • The nano-platforms for theranostics by utilizing protein nanoparticles are reviewed. • Protein nanoparticles-based theranostics has good and tunable imaging and therapeutic modalities • Current defects and prospects of protein nanoparticles are also discussed. [ABSTRACT FROM AUTHOR]

Sorption of doxorubicin (Dox) on Fe3O4 magnetic nanoparticles coated with iron and silicon glycerolates (ISG-MNPs) was studied. The Dox sorption experiments were carried out in water at different concentrations of ISG-MNPs and Dox. The loading efficiency was assessed by UV spectroscopy. It was demonstrated that at an ISG-MNPs concentration of 0.2 wt.%, an increase in the Dox: ISG-MNPs ratio (from 0.20 to 1.55 w/w) leads to a slow increase in the drug loading capacity (LC) from about 3 to 5%; in this case, the loading efficiency (LE) abruptly decreases from 43 to 6%. A decrease in the ISG-MNPs concentration from 1.0 to 0.5 wt.% (at 0.3 wt.% Dox) leads to an increase in LC from 5.0 to 6.7%. In vitro experiments demonstrated dose-dependent cytotoxicity of the synthesized nanomaterial against human rhabdosarcoma (RD) cells, viz., the statistically significant toxicity of Dox-loaded ISG-MNPs was evident for a nanoconjugate solution with a concentration of 10 µg mL−1, and the cell survival in solutions with a concentration of 100 µg mL−1 was 57%. [ABSTRACT FROM AUTHOR]

Heating magnetic nanoparticles (MNPs) with alternating magnetic fields (AMFs) have applications in biomedical research and cancer therapy. Accurate measurement of the heating efficiency or specific loss power (SLP) generated by the MNPs is essential to assess response(s) in biological systems. Efforts to develop standardized equipment and to harmonize results obtained from various MNP samples and AMF systems have met with little success. Without a standardized magnetic nanoparticle or calorimeter device, objective comparisons of estimated thermal output among laboratories remain a challenge. In addition, the most widely used adiabatic initial slope model fails to account for thermal losses, which are unavoidable. We propose a non-adiabatic method to analyze MNP heating efficiency derived from the Box–Lucas equation, wherein the sample is subjected to several short duration heating pulses. SLP is then estimated from an arithmetic average of the Box–Lucas fitted coefficients obtained from each pulse. Heating experiments were conducted with two identical samples that were placed within vessels having different thermal insulation using the same AMF parameters. Though the samples generated different temperature curves, the pulsed Box–Lucas method produced nearly equivalent SLP estimates. Further, the pulsed test enabled analysis of the heat transfer coefficient providing quantitative measures of sample heat loss throughout the test, with robust statistical confidence. We anticipate this new methodology will aid efforts to standardize measurements of MNP heating efficiency, enabling direct comparison among varied systems. [ABSTRACT FROM AUTHOR]

In this investigation, we synthesized nano-sized perovskite LSMO and Cu-doped LSMCx materials using the sol–gel method, exhibiting appropriate Curie temperatures and magnetic attributes conducive to the application of self-controlled hyperthermia. Centrifugal separation has been used to reduce particle size distribution and thus analyze magnetic properties dependent on mean particle size. Structural analysis was conducted using X-ray Powder Diffraction. The composition was determined through X-ray Photoelectron Spectroscopy, while topographical features were scrutinized employing Scanning Electron Microscopy. Magnetic properties were evaluated employing a Vibrating Sample Magnetometer, and the magneto-thermal characteristics were delineated using an Alternating Magnetic Field hyperthermia system. Notably, this study marks the pioneering identification of La1−xSrxMnO3 as a viable material candidate for auto-regulated hyperthermia, based on its magnetization range (5–20 emu/g) and Curie temperature span (287–357 K) that are changing with the mean particle size. Through comprehensive analysis, we thoroughly investigated its hyperthermia attributes, thereby contributing significant insights to the existing literature. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) have found extensive application in the biomedical domain due to their enhanced biocompatibility, minimal toxicity, and strong magnetic responsiveness. MNPs exhibit great potential as nanomaterials in various biomedical applications, including disease detection and cancer therapy. Typically, MNPs consist of a magnetic core surrounded by surface modification coatings, such as inorganic materials, organic molecules, and polymers, forming a nucleoshell structure that mitigates nanoparticle agglomeration and enhances targeting capabilities. Consequently, MNPs exhibit magnetic responsiveness in vivo for transportation and therapeutic effects, such as enhancing medical imaging resolution and localized heating at the site of injury. MNPs are utilized for specimen purification through targeted binding and magnetic separation in vitro, thereby optimizing efficiency and expediting the process. This review delves into the distinctive functional characteristics of MNPs as well as the diverse bioactive molecules employed in their surface coatings and their corresponding functionalities. Additionally, the advancement of MNPs in various applications is outlined. Additionally, we discuss the advancements of magnetic nanoparticles in medical imaging, disease treatment, and in vitro assays, and we anticipate the future development prospects and obstacles in this field. The objective is to furnish readers with a thorough comprehension of the recent practical utilization of MNPs in biomedical disciplines. [ABSTRACT FROM AUTHOR]

Despite the recognized potential of nanoparticles, only a few formulations have progressed to clinical trials, and an even smaller number have been approved by the regulatory authorities and marketed. Virus-like particles (VLPs) have emerged as promising alternatives to conventional nanoparticles due to their safety, biocompatibility, immunogenicity, structural stability, scalability, and versatility. Furthermore, VLPs can be surface-functionalized with small molecules to improve circulation half-life and target specificity. Through the functionalization and coating of VLPs, it is possible to optimize the response properties to a given stimulus, such as heat, pH, an alternating magnetic field, or even enzymes. Surface functionalization can also modulate other properties, such as biocompatibility, stability, and specificity, deeming VLPs as potential vaccine candidates or delivery systems. This review aims to address the different types of surface functionalization of VLPs, highlighting the more recent cutting-edge technologies that have been explored for the design of tailored VLPs, their importance, and their consequent applicability in the medical field. [ABSTRACT FROM AUTHOR]

Immobilization of enzymes is a very attractive technique to develop efficient and cost-effective bioprocesses. In present investigation, immobilization of partially purified α-galactosidase from Penicillium aculeatum APS1 (APS1αgal) was carried out on chitosan coated magnetic nanoparticles, Fe3O4. Immobilization conditions such as enzyme concentration, amount of chitosan coated magnetic nanoparticles (CMNP), pH and time for immobilization were optimised and maximum immobilization yield of 45 ± 2% and activity yield of 47 ± 3% were achieved. Immobilized particles were characterised by thermal analysis and Fourier transform infrared spectroscopy (FT-IR). The surface morphology of particles was studied by scanning electron microscopy (SEM). Moreover, biochemical properties of free and immobilized enzymes were compared. Thermostability and storage stability of APS1αgal were found to be improved after immobilization. Reusability of immobilized APS1αgal was assessed and it was found to retain 65% activity after 12 consecutive cycles. Further experiments were conducted to assess the ability of immobilized APS1αgal for removal of raffinose family oligosaccharides (RFO) in soymilk. During batch hydrolysis, about 80% removal of RFO was achieved. Hydrolysis of RFO was confirmed by TLC analysis. Immobilized APS1αgal was able to carry out hydrolysis of RFO up to 45% even after 7 cycles. Overall, results of this study show the potential of immobilized APS1αgal for efficient removal of non-digestible RFO in soymilk. [ABSTRACT FROM AUTHOR]

The current research article has investigated the synthesis and characterization of novel iron nanoparticles (INPs) from neem and betel leaves extract combination using response surface methodology–central composite design and coated with chitosan–curcumin (CCINPs) as a biocompatible and contrast agent for magnetic resonance imaging (MRI). The coating of INPs with chitosan and curcumin (CCINPs) was carried out using a simple, easy, chemical‐free ultrasonication method and characteristics were confirmed by UV–visible (Vis) spectrophotometer (UV–Vis), Fourier‐transform infrared spectroscopy, X‐ray diffraction, scanning electron microscope, atomic force microscopy, and vibrating sample magnetometer. The biocompatibility of the particles was ensured by conducting hemolytic and cell viability assays. The nanoparticle was found to be nonhemolytic (<5%) up to 150 μg/mL for both INPs and CCINPs. The cell viability was stable (peripheral blood mononuclear cells‐PBMCs) till 48 h at 150 μg/mL of INPs and CCINPs. Both the test results produced were found to be biocompatible and additionally, an in vitro MRI study of INPs and CCINPs demonstrated the efficiency of the nanoparticle as a negative contrast agent with enhanced contrast nature in CCINPs. Thus, overall results indicate that the green synthesized chemical‐free novel CCINPs could be a potential candidate for a wide range of applications such as MRI, drug delivery, and in magnetic fluid hyperthermia. [ABSTRACT FROM AUTHOR]

Cancer cells have higher heat sensitivity compared to normal cells; therefore, hyperthermia is a promising approach for cancer therapy because of its ability to selectively kill cancer cells by heating them. However, the specific and rapid heating of tumor tissues remains challenging. This study investigated the potential of magnetic nanoparticles (MNPs) modified with tumor-homing peptides (THPs), specifically PL1 and PL3, for tumor-specific magnetic hyperthermia therapy. The synthesis of THP-modified MNPs involved the attachment of PL1 and PL3 peptides to the surface of the MNPs, which facilitated enhanced tumor cell binding and internalization. Cell specificity studies revealed an increased uptake of PL1- and PL3-MNPs by tumor cells compared to unmodified MNPs, indicating their potential for targeted delivery. In vitro hyperthermia experiments demonstrated the efficacy of PL3-MNPs in inducing tumor cell death when exposed to an alternating magnetic field (AMF). Even without exposure to an AMF, an additional ferroptotic pathway was suggested to be mediated by the nanoparticles. Thus, this study suggests that THP-modified MNPs, particularly PL3-MNPs, hold promise as a targeted approach for tumor-specific magnetic hyperthermia therapy. [ABSTRACT FROM AUTHOR]

Among brain tumors, glioblastoma (GBM) is very challenging to treat as chemotherapeutic drugs can only penetrate the brain to a limited extent due to the blood–brain barrier (BBB). Nanoparticles can be an attractive solution for the treatment of GBM as they can transport drugs across the BBB into the tumor. In this study, normal and GBM organoids comprising six brain cell types were developed and applied to study the uptake, BBB penetration, distribution, and efficacy of fluorescent, ultrasmall gold nanoparticles (AuTio-Dox-AF647s) conjugated with doxorubicin (Dox) and AlexaFluor-647-cadaverine (AF647) by confocal laser scanning microscopy (CLSM), using a mixture of dissolved doxorubicin and fluorescent AF647 molecules as a control. It was shown that the nanoparticles could easily penetrate the BBB and were found in normal and GBM organoids, while the dissolved Dox and AF647 molecules alone were unable to penetrate the BBB. Flow cytometry showed a reduction in glioblastoma cells after treatment with AuTio-Dox nanoparticles, as well as a higher uptake of these nanoparticles by GBM cells in the GBM model compared to astrocytes in the normal cell organoids. In summary, our results show that ultrasmall gold nanoparticles can serve as suitable carriers for the delivery of drugs into organoids to study BBB function. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles attached to hydrophilic polymer brushes containing immobilized Fe3+ ions were synthesized and used as a new strategy for phosphopeptide enrichment from digested tryptic proteins. To test the performance of nanoparticles in phosphopeptide enrichment, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used. Magnetic nanoparticles with the following features such as high adsorption capacity (about 360 mg/g), easy control and transfer by external magnetic field (high magnetic saturation, about 50 emu/g), excellent phosphopeptide recovery (93.4%) and no shadow effect (due to their non-porous structure), were synthesized. It has been shown that the presence of other proteins in high concentrations does not affect on the performance of nanoparticles. Furthermore, the lowest concentration of digested β-casein phosphopeptides detectable by nanoparticles was determined to be approximately 0.5 fmol µL− 1. The function of synthesized nanoparticles to enrich phosphopeptides in complex biological samples was also demonstrated by isolating four endogenous phosphopeptides from human serum. [ABSTRACT FROM AUTHOR]

Nanoparticles composed of inorganic boron-containing compounds represent a promising candidate as 10B carriers for BNCT. This study focuses on the synthesis, characterization, and assessment of the biological activity of composite nanomaterials based on boron carbide (B4C). Boron carbide is a compelling alternative to borated molecules due to its high volumetric B content, prolonged retention in biological systems, and low toxicity. These attributes lead to a substantial accumulation of B in tissues, eliminating the need for isotopically enriched compounds. In our approach, B4C nanoparticles were included in composite nanostructures with ultrasmall superparamagnetic nanoparticles (SPIONs), coated with poly (acrylic acid), and further functionalized with the fluorophore DiI. The successful internalization of these nanoparticles in HeLa cells was confirmed, and a significant uptake of 10B was observed. Micro-distribution studies were conducted using intracellular neutron autoradiography, providing valuable insights into the spatial distribution of the nanoparticles within cells. These findings strongly indicate that the developed nanomaterials hold significant promise as effective carriers for 10B in BNCT, showcasing their potential for advancing cancer treatment methodologies. [ABSTRACT FROM AUTHOR]

Currently, one of the main causes of death in the world is cancer; therefore, it is urgent to obtain a precocious diagnosis, as well as boost research and development of new potential treatments, which should be more efficient and much less invasive for the patient. Magnetic hyperthermia (MH) is an emerging cancer therapy using nanoparticles, which has proved to be effective when combined with chemotherapy, radiotherapy and/or surgery, or even by itself, depending on the type and location of the tumor's cells. This article presents the results obtained by using a previously developed economic homemade hyperthermia device with different types of magnetite nanoparticles, with sizes ranging between 12 ± 5 and 36 ± 11 nm and presenting different shapes (spherical and cubic particles). These magnetic nanoparticles (MNPs) were synthesized by three different methods (co-precipitation, solvothermal and hydrothermal processes), with their final form being naked, or possessing different kinds of covering layers (polyethylene glycol (PEG) or citric acid (CA)). The parameters used to characterize the heating by magnetic hyperthermia, namely the Specific Absorption Rate (SAR) and the intrinsic loss power (ILP), have been obtained by two different methods. Among other results, these experiments allowed for the determination of which synthesized MNPs showed the best performance concerning hyperthermia. From the results, it may be concluded that, as expected, the shape of MNPs is an important factor, as well as the time that the MNPs can remain suspended in solution (which is directly related to the concentration and covering layer of the MNPs). The MNPs that gave the best results in terms of the SAR were the cubic particles covered with PEG, while in terms of total heating the spherical particles covered with citric acid proved to be better. [ABSTRACT FROM AUTHOR]

Driving immobilized, single-domain magnetic nanoparticles at high frequency by square wave fields instead of sinusoidal waveforms leads to qualitative and quantitative improvements in their performance both as point-like heat sources for magnetic hyperthermia and as sensing elements in frequency-resolved techniques such as magnetic particle imaging and magnetic particle spectroscopy. The time evolution and the frequency spectrum of the cyclic magnetization of magnetite nanoparticles with random easy axes are obtained by means of a rate-equation method able to describe time-dependent effects for the particle sizes and frequencies of interest in most applications to biomedicine. In the presence of a high-frequency square-wave field, the rate equations are shown to admit an analytical solution and the periodic magnetization can be therefore described with accuracy, allowing one to single out effects which take place on different timescales. Magnetic hysteresis effects arising from the specific features of the square-wave driving field results in a breakthrough improvement of both the magnetic power released as heat to an environment in magnetic hyperthermia treatments and the magnitude of the third harmonic of the frequency spectrum of the magnetization, which plays a central role in magnetic particle imaging. [ABSTRACT FROM AUTHOR]

Background: Radiation nanomedicines are nanoparticles labeled with radionuclides that emit α- or β-particles or Auger electrons for cancer treatment. We describe here our 15 years scientific journey studying locally-administered radiation nanomedicines for cancer treatment. We further present a view of the radiation nanomedicine landscape by reviewing research reported by other groups. Main body: Gold nanoparticles were studied initially for radiosensitization of breast cancer to X-radiation therapy. These nanoparticles were labeled with 111In to assess their biodistribution after intratumoural vs. intravenous injection. Intravenous injection was limited by high liver and spleen uptake and low tumour uptake, while intratumoural injection provided high tumour uptake but low normal tissue uptake. Further, [111In]In-labeled gold nanoparticles modified with trastuzumab and injected iintratumourally exhibited strong tumour growth inhibition in mice with subcutaneous HER2-positive human breast cancer xenografts. In subsequent studies, strong tumour growth inhibition in mice was achieved without normal tissue toxicity in mice with human breast cancer xenografts injected intratumourally with gold nanoparticles labeled with β-particle emitting 177Lu and modified with panitumumab or trastuzumab to specifically bind EGFR or HER2, respectively. A nanoparticle depot (nanodepot) was designed to incorporate and deliver radiolabeled gold nanoparticles to tumours using brachytherapy needle insertion techniques. Treatment of mice with s.c. 4T1 murine mammary carcinoma tumours with a nanodepot incorporating [90Y]Y-labeled gold nanoparticles inserted into one tumour arrested tumour growth and caused an abscopal growth-inhibitory effect on a distant second tumour. Convection-enhanced delivery of [177Lu]Lu-AuNPs to orthotopic human glioblastoma multiforme (GBM) tumours in mice arrested tumour growth without normal tissue toxicity. Other groups have explored radiation nanomedicines for cancer treatment in preclinical animal tumour xenograft models using gold nanoparticles, liposomes, block copolymer micelles, dendrimers, carbon nanotubes, cellulose nanocrystals or iron oxide nanoparticles. These nanoparticles were labeled with radionuclides emitting Auger electrons (111In, 99mTc, 125I, 103Pd, 193mPt, 195mPt), β-particles (177Lu, 186Re, 188Re, 90Y, 198Au, 131I) or α-particles (225Ac, 213Bi, 212Pb, 211At, 223Ra). These studies employed intravenous or intratumoural injection or convection enhanced delivery. Local administration of these radiation nanomedicines was most effective and minimized normal tissue toxicity. Conclusions: Radiation nanomedicines have shown great promise for treating cancer in preclinical studies. Local intratumoural administration avoids sequestration by the liver and spleen and is most effective for treating tumours, while minimizing normal tissue toxicity. [ABSTRACT FROM AUTHOR]

Ferromagnetic metallic cobalt and nickel nanoparticles were synthesized by intramolecular metal-hydrazine ligand oxidation reduction reaction in basic media and the solid state. Nickel nanoparticles Ni1 and Ni2 are obtained from two complexes, Ni(N2H4)2(C2O4) and Ni(N2H4)2(HCO2)2, respectively. X-ray powder diffraction (XRD) and energy-dispersive X-ray (EDX) data show pure fcc crystal structures of nanoparticles. Scanning electron microscopy (SEM) images revealed both Ni1 and Ni2 nanoparticles have agglomerated sphere morphologies. The crystallite size estimated by using the Scherer method for Ni1 and Ni2 were 18.7 and 6.2 nm. Vibrating sample magnetometer (VSM) data show the coercivity of metallic nickel samples Ni1 and Ni2 are 50 and 153 Oe, respectively. Both nanoparticles cause an increase in the temperature of water under applied alternative magnetic field and showed specific loss power (SLP) of 70 W/g and 104.8 W/g, respectively. The same method is used in preparation of cobalt nanoparticles from two complexes, Co(N2H4)2(C2O4) and Co(N2H4)2(HCO2)2. XRD analysis data show both nanoparticles have hcp crystal structure. SEM images show nanosheet structure with sheet thickness of 10 to 30 nm. Coercivity of Co1 and Co2 nanoparticles obtained by VSM and Hc are 182 and 171 Oe, respectively. In spite of high coercivity in both Co1 and Co2 nanoparticles, the magnetic hyperthermia heating effects are not observed in practice and specific loss power (SLP) is zero. [ABSTRACT FROM AUTHOR]

An exciting prospect in the field of magnetic fluid hyperthermia (MFH) has been the integration of noble rare earth elements (Eu) with biopolymers (chitosan/dextran) that have optimum structures to tune specific effects on magnetic nanoparticles (NPs). However, the heating efficiency of MNPs is primarily influenced by their magnetization, size distribution, magnetic anisotropy, dipolar interaction, amplitude, and frequency of the applied field, the MNPs with high heating efficiency are still challenging. In this study, a comprehensive experimental analysis has been conducted on single-domain magnetic nanoparticles (SDMNPs) for evaluating effective anisotropy, assessing the impact of particle-intrinsic factors and experimental conditions on self-heating efficiency in both noninteracting and interacting systems, with a particular focus on the dipolar interaction effect. The study successfully reconciles conflicting findings on the interaction effects in the agglomeration and less agglomerated arrangements for MFH applications. The results suggest that effective control of dipolar interactions can be achieved by encapsulating Chitosan/Dextran in the synthesized MNPs. The lower dipolar interactions successfully tune the self-heating efficiency and hold promise as potential candidates for MFH applications. [ABSTRACT FROM AUTHOR]

Magnetotactic bacteria produce magnetite nanoparticles called magnetosomes at ambient conditions via a protein‐stabilized transient amorphous precursor to obtain precise control over particle size and morphology. In a bioinspired approach, such biomineralization processes are emulated, mimicking proteins involved in magnetosome formation using the positively charged analog poly‐L‐arginine. While the additive is expensive, it remains elusive whether the change in magnetite formation mechanism arises solely from the polymer's cationic nature. This study uses different mass‐produced and sustainably sourced polycations to induce the biomineralization‐reminiscent formation of magnetite nanoparticles. These findings present how to achieve control over nanoparticle size (from 10 to 159 nm) and morphology (compact and sub‐structured) as well as magnetic properties (superparamagnetic, stable‐single‐domain, vortex state) at ambient temperature and pressure using these additives. Furthermore, the formation of large nanoparticles with the addition of poly(diallyldimethylammonium chloride) (PDADMAC) at low alkalinity highlights how magnetotactic bacteria may produce magnetite nanoparticles under similar conditions. Confirming the polycations' ability to electrostatic stabilize amorphous ferrihydrite, it is anticipated that parametric in vitro studies on polymer properties will provide valuable insights into magnetite biomineralization and aid in rationally designing magnetic nanomaterials. [ABSTRACT FROM AUTHOR]

A novel platform on which anti-prostate specific membrane antigen (PSMA) antibodies were immobilized on the core–shell structure of iron oxide (Fe3O4)/6-phosphonohexanoic acid (6Pha) nanoparticles was developed for the specific detection of PSMA. The Fe3O4@SiO2@6Pha nanoparticles were selected as an immune sensing platform, and external magnetic force provided separation of the target PSMA antigen in biological samples. The core–shell Fe3O4@SiO2@6Pha nanoparticles conjugated with anti-PSMA antibodies were utilized for PSMA concentration measurement. The analysis strategy was based on the direct binding of anti-PSMA antibodies to the target PSMA antigens. Different electrochemical analysis approaches were utilized to characterize the biosensing system. The differences in impedimetric signals before and after interaction with PSMA antigens were associated directly with the PSMA concentration. Under optimized conditions, the linear range of 7.5–1250 pg mL−1, the detection limit of 2.21 pg mL−1, and the quantification limit of 7.36 pg mL−1 were obtained. The applicability of the immunosensor was tested on diluted human serum samples, and satisfactory results were obtained. The results illustrate that a reliable, robust, selective, and simple detection strategy was developed for further clinical diagnosis. [ABSTRACT FROM AUTHOR]

High cost and low operational stability are the most important challenges limiting the possible use of laccase in the removal of textile dyes. To overcome these challenges, in this study, polyvinylpyrrolidone (PVP)-coated magnetic nanoparticles (MNPs) were produced and characterized. To our knowledge, this is the first study to explore the feasibility of immobilizing a Trametes trogii laccase enzyme on Fe3O4/PVP MNPs. The characterization of samples and the successful immobilization of laccase were verified by characterization methods. Besides, the biochemical properties and stability of the Fe3O4/PVP/Lac were evaluated in terms of optimum pH, optimum temperature, thermostability, thermodynamic and kinetic parameters, storage stability, operational stability, and decolorization efficiency of two different textile dyes. The optimum activities were recorded at pH 2.5 °C and 30 °C. The Fe3O4/PVP/Lac displayed remarkable thermal stability and activation energy for denaturation, enthalpy, Gibbs free energy, and entropy results confirmed the enhanced stability of Fe3O4/PVP/Lac against high temperatures. Meanwhile, the Fe3O4/PVP/Lac retained about 58% of its original activity after seven consecutive reuses, while it retained up to 25% of its original activity after 28 d of storage at room temperature. Km and Vmax for the Fe3O4/PVP/Lac were calculated to be 126 µM and 211 µmol/min, respectively. Finally, after 8 and 6 cycles of repeated use, the Fe3O4/PVP/Lac still decolorized 32.34% and 32.23% of Remazol Brilliant Blue R (RBBR) and Indigo Carmine (IC), respectively. As envisioned, this study suggests a promising way to solve the problems of high price and poor operational stability of the enzyme during biocatalytic decolorization of textile dyes in wastewaters. [ABSTRACT FROM AUTHOR]

The heat transport that takes place in living tissue during magnetic tumor hyperthermia is described in this study using the nonlocal bioheat model in spherical coordinates. In magnetic fluid hyperthermia, it is crucial to regulate the therapeutic temperature. This paper suggests a hybrid numerical approach that employs the Laplace transforms, change of variables, and modified discretization techniques, coupled with nonlocal hyperbolic shape function, to tackle the present problem. This study investigates the impacts of nonlocal parameter and the disparity in thermophysical properties between diseased and healthy tissue. A graph is displayed to represent the numerical temperature results. The validity of the numerical findings is demonstrated by comparing them with the results reported in previous literature. [ABSTRACT FROM AUTHOR]

The synthesis of magnetic nanoparticles enclosed in zeolitic imidazolate frameworks (MNPs@ZIF-8) was successful carried out at ambient temperature and atmospheric pressure. The synthesis procedure was selected because it is uncomplicated and does not call for the use of any sophisticated pieces of apparatus throughout its execution. The Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) images were investigated to characterize the materials. The analysis of the data allowed MNPs@ZIF-8 to evolve into a highly crystalline phase with particles ranging in size from 50 to 100 nanometers. This was made feasible by the fact that the phase could be created. It was explored whether or not MNPs@ZIF-8 was effective as a nanocarrier for the delivery of natural medicines like crocin. It was demonstrated to be very biocompatible and had an IC50 value of > 1000 μg/mL, which is the concentration at which half of the maximum inhibitory effect is produced. The IC50 value for crocin-loaded MNPs-ZIF-8 was 419 ± 0 μg/mL, which was roughly half of the IC50 value for pure crocin, which was 716 ± 160 μg/mL. [ABSTRACT FROM AUTHOR]

Objective(s): Colorectal cancer is the second deadly cancer for men and women worldwide. Depending on the pathological attributes of the tumor, there are numerous therapeutic options for colorectal cancer treatment. Chemotherapy is one of the main methods, however, due to the low solubility and short half-life of chemotherapy drugs, this treatment method has limitations. 5-Fu and curcumin are important drugs for the treatment of colorectal cancer. One of the primary resolutions is the application of bioanalytical techniques, which involve the utilization of chemotherapy agents in conjunction with nanoparticles, thereby facilitating the directed transportation of the therapeutic substance to malignant cells. Materials and Methods: In this study, Polycaprolactone-Polyethylene glycol-Hyaluronic acid (PCL-PEGHA) copolymers and magnetic nanoparticle iron-cobalt (FeCo) were synthesized to deliver Curcumin (CU), 5-Fluorouracil (5-Fu) and the combination to HCT116 colorectal cancer cells. To control the release of CU and 5-FU and in vivo tumor targeting, PCL-PEG-HA/FeCo were synthesized and then characterized for the morphological characteristics, shape, and magnetic properties of the nanoparticles, drug retention efficiency, and release pattern in two acidic and neutral environments. Results: Our results demonstrated that the release profile of CU and 5-FU from the nanoparticles in acidic conditions was more than the drug release in neutral conditions. In acidic conditions, due to faster degradation of nanoparticles, drugs are released faster. Moreover, these nanoparticles have high biocompatibility and potential in transporting CU and 5-FU drugs to HCT116 cells. The IC50 of co-delivery of CU and 5-FU was 65.42 mg/L, while, the IC50 value of drugs coated with nanoparticles (PCL-PEG-HA/FeCo/5-FU/Curcumin) was 72.26. Otherwise, utilizing nanoparticles can increase the amount of apoptosis compared to control and free 5-Fu and Curcumin. Conclusion: In conclusion, PCL-PEG-HA/FeCo/5-FU/Curcumin nanoparticles can be an efficient solution in targeted drug delivery to colorectal cancer cells and reducing the side effects of these drugs on normal cells. [ABSTRACT FROM AUTHOR]

In this investigation, specimens of magnetic nanoparticles (MNPs) consisting of Fe2O3, Fe3O4, and CoFe2O4 were synthesized in a powdered state through the co-precipitation technique. X-ray diffraction was employed for the purpose of characterizing the dimensions of the sample, yielding the following measurements: t = 64, 10, and 13 nm, respectively. Subsequently, a series of suspensions (S1, S5, S10, S15, and S20) were prepared by introducing varying amounts (x = 1, 5, 10, 15, and 20 mg) of magnetic nanoparticles into 1 ml of distilled water. A low-frequency induction heater was employed to investigate the thermal characteristics of the aforementioned MNPs. The experimental findings indicate that as the concentration of MNPs in the suspension increases, there is a corresponding decrease in the maximum temperature (Tmax) measured in degrees Celsius, the heating rate (∆T/∆t) measured in degrees Celsius per second, and the specific absorption rate measured in watts per gram. Furthermore, the conducted investigation has elucidated that these MNPs exhibit commendable thermal characteristics, thereby signifying their potential utility in the realm of magnetic hyperthermia treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] The adsorption of proteins onto the surface of nanoparticle (NP) leads to the formation of the so-called "protein corona" as consisting both loosely and tightly bound proteins. It is well established that the biological identity of NPs that may be acquired after exposure to a biological matrix is mostly provided by the components of the hard corona as the pristine surface is generally less accessible for binding. For that reason, the isolation and the characterisation of the NP-corona complexes and identification of the associated biomolecules can help in understanding its biological behaviour. Established methods for the isolation of the NP-HC complexes are time-demanding and can lead to different results based on the isolation method applied. Herein, we have developed a fast and simple method using ferromagnetic beads isolated from commercial MACS column and used for the isolation of superparamagnetic NP following exposure to different types of biological milieu. We first demonstrated the ability to easily isolate superparamagnetic iron oxide NPs (IONPs) from different concentrations of human blood plasma, and also tested the method on the corona isolation using more complex biological matrices, such as culture medium containing pulmonary mucus where the ordinary corona methods cannot be applied. Our developed method showed less than 20% difference in plasma corona composition when compared with centrifugation. It also showed effective isolation of NP-HC complexes from mucus-containing culture media upon comparing with centrifugation and MACS columns, which failed to wash out the unbound proteins. Our study was supported with a full characterisation profile including dynamic light scattering, nanoparticle tracking analysis, analytical disk centrifuge, and zeta potentials. The biomolecules/ proteins composing the HC were separated by vertical gel electrophoresis and subsequently analysed by liquid chromatography-tandem mass spectrometry. In addition to our achievements in comparing different isolation methods to separate IONPs with corona from human plasma, this is the first study that provides a complete characterisation profile of particle protein corona after exposure in vitro to pulmonary mucus-containing culture media. [ABSTRACT FROM AUTHOR]

A magnetocaloric effect (MCE) with sizable isothermal entropy change (ΔS) maintained over a broad range of temperatures above the blocking temperature is reported for a rare earth-free superparamagnetic nanoparticle system comprising of Fe–TiN heterostructure. Superparamagnetic iron (Fe) particles were embedded in a titanium nitride (TiN) thin film matrix in a TiN/Fe/TiN multilayered pattern using a pulsed laser deposition method. High angle annular dark-field images in conjunction with dispersive energy analysis, recorded using scanning transmission electron microscopy, show a clear presence of alternating layers of Fe and TiN with a distinct atomic number contrast between Fe particles and TiN. Quantitative information about the isothermal entropy change (ΔS) and the magnetocaloric effect in the multilayer Fe–TiN system has been obtained by applying Maxwell relation to the magnetization vs temperature data at various fields. With the absence of a dynamic magnetic hysteresis above the blocking temperature, the negative ΔS as high as 4.18 × 103 J/Km3 (normal or forward MCE) is obtained at 3 T at 300 K. [ABSTRACT FROM AUTHOR]

In this paper, we present the results of a study of the properties of silver and copper nanoparticle (NP) ensembles and Fe3O4:Gd:B composites, which are promising for their potential uses in biomedicine. Magnetic resonance is applied as the main method of analysis. The magnetic properties of the NPs are found to be highly sensitive to the nanoparticle size, which enables finding the size distributions of metal NPs, using magnetic measurements. The dependence of the magnetic properties of lyophilized ensembles of Ag and Cu NPs on the interaction with molecular oxygen is revealed. The composites magnetic system Fe3O4:Gd:B is a key component of a promising method for neutron-capture therapy. The magnetic properties of this system, which are the result of differences in the g-factors of its components, are described in detail. As a consequence, the dependence of the resulting g-factor on the ratio of the components is established. [ABSTRACT FROM AUTHOR]

Objectives Demonstrate the potential application of a novel, endoscope-like device to guide and focus an alternating magnetic field (AMF) for treating deep-seated cancers via magnetic nanoparticle hyperthermia (MNPH).Methods AMF delivery, MNP activation, and eddy current distribution characteristics are investigated through experimental studies in phantoms and computational simulations using a full 3-dimensional human model. The 3D simulations compare the novel device to traditional AMF designs, including a MagForce-like, two-coil system (used clinically) and a single surface-coil system.Results The results demonstrate that this approach can deliver the same magnetic field strength at the prostate’s centroid as traditional AMF designs, while reducing eddy current heating by 2 to 6 times. At the same level of normal tissue heating, this method provides 5.0 times, 1.5 times, and 0.92 times the magnetic field strength to the nearest, centroid, and farthest regions of the prostate, respectively.Conclusions These results demonstrate proof-of-concept for an endoscopic magnetic field guiding and focusing system capable of delivering clinically relevant AMF from a distance. This innovative approach offers a promising alternative to conventional field delivery methods by directing AMF through the body, concentrating it in the tumor region, reducing eddy currents in surrounding healthy tissue, and avoiding exposure of nearby metallic implants.

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]