Use Of Magnetic Nanoparticles Research Articles

Cellulase Immobilization on Nanostructured Supports for Biomass Waste Processing.

Nanobiocatalysts, i.e., enzymes immobilized on nanostructured supports, received considerable attention because they are potential remedies to overcome shortcomings of traditional biocatalysts, such as low efficiency of mass transfer, instability during catalytic reactions, and possible deactivation. In this short review, we will analyze major aspects of immobilization of cellulase-an enzyme for cellulosic biomass waste processing-on nanostructured supports. Such supports provide high surface areas, increased enzyme loading, and a beneficial environment to enhance cellulase performance and its stability, leading to nanobiocatalysts for obtaining biofuels and value-added chemicals. Here, we will discuss such nanostructured supports as carbon nanotubes, polymer nanoparticles (NPs), nanohydrogels, nanofibers, silica NPs, hierarchical porous materials, magnetic NPs and their nanohybrids, based on publications of the last five years. The use of magnetic NPs is especially favorable due to easy separation and the nanobiocatalyst recovery for a repeated use. This review will discuss methods for cellulase immobilization, morphology of nanostructured supports, multienzyme systems as well as factors influencing the enzyme activity to achieve the highest conversion of cellulosic biowaste into fermentable sugars. We believe this review will allow for an enhanced understanding of such nanobiocatalysts and processes, allowing for the best solutions to major problems of sustainable biorefinery.

Use of magnetic nanoparticles and inductive heating as means to reduce wait on cement time

Use of magnetic nanoparticles and inductive heating as means to reduce wait on cement time

Magnetic Nanoparticles: An Overview for Biomedical Applications

The use of magnetic nanoparticles has greatly expanded for numerous biomedical applications over the past two decades due to their high surface area, size-dependent superparamagnetic properties, precision tunability, and easy surface modification. Magnetic nanoparticles can be engineered and manipulated with other nanoparticles and functional compounds to form multi-modal systems useful in theragnosis. However, superior biocompatibility, high loading efficacy, regulated drug release, and in vitro and in vivo stability are necessary for the efficient incorporation of these nanoparticles into physiological systems. In recent years, considerable advancements have been made and reported both in synthesis and application, given the broad range of biomedical-related prospective uses of magnetic nanoparticles. Here, in this review, we have highlighted some essential works, specifically related to the application of magnetic nanoparticles in drug delivery, magnetic hyperthermia, magnetic resonance imaging, magnetic particle imaging, biosensors, and tissue engineering.

12012 fundamental mechanisms behind nanotechnology applications in oil and gas: Emerging nano-EOR processes

As the important role of enhanced oil recovery (EOR) in meeting the world’s energy requirement is growing, use of nanoparticles in lieu of, or in combination with, the existing EOR agents to expand EOR’s applicable range is receiving significant attention. Two of the most actively investigated applications are: 1) wettability alteration by addition of nanoparticles into the waterflood injection water, and 2) use of nanoparticle-stabilized Pickering foams and emulsions mainly for EOR process mobility control. As comprehensive reviews are recently available on these topics, two other emerging nanoparticle applications are critically reviewed here: 1) nanoparticle addition for enhanced polymer flooding, and 2) use of magnetic nanoparticles for oil displacement control. Three and five proposed mechanisms of these two applications are critically reviewed, respectively. The most recent progresses are covered, and the challenges and possible future works are discussed.

Theranostic Applications of an Ultra-Sensitive T1 and T2 Magnetic Resonance Contrast Agent Based on Cobalt Ferrite Spinel Nanoparticles.

Simple SummaryMagnetic nanoparticles (MNPs) represent an important class of nanomaterials that has been actively employed in multiple technological applications. The MNPs and their based composites have been intensively developed for magnetic resonance imaging, targeted drug delivery, magnetic hyperthermia, and other applications. Magnetic Resonance Imaging (MRI) has a prominent position among clinical imaging modalities as it allows for high spatial resolution and tissue specificity without harmful ionizing radiation. The aim of the study was the demonstration of the potential use of magnetic nanoparticles based on cobalt ferrite spinel as advanced MRI contrast agents that are capable of both T1-weighted positive and T2-weighted negative contrast enhancements in vitro and in vivo. Furthermore, in the present study, we combined novel physical, chemical, and biomedical approaches to develop a multifunctional MRI-detectable drug delivery system that was an efficient T1- and T2-weighted MRI contrast agent and a nanocarrier for targeted drug delivery in vivo.Nano-dimensional materials have become a focus of multiple clinical applications due to their unique physicochemical properties. Magnetic nanoparticles represent an important class of nanomaterials that are widely studied for use as magnetic resonance (MR) contrast and drug delivery agents, especially as they can be detected and manipulated remotely. Using magnetic cobalt ferrite spinel (MCFS) nanoparticles, this study was aimed at developing a multifunctional drug delivery platform with MRI capability for use in cancer treatment. We found that MCFS nanoparticles demonstrated outstanding properties for contrast MRI (r1 = 22.1 s–1mM–1 and r2 = 499 s–1mM–1) that enabled high-resolution T1- and T2-weighted MRI-based signal detection. Furthermore, MCFS nanoparticles were used for the development of a multifunctional targeted drug delivery platform for cancer treatment that is concurrently empowered with the MR contrast properties. Their therapeutic effect in systemic chemotherapy and unique MRI double-contrast properties were confirmed in vivo using a breast cancer mouse tumor model. Our study thus provides an empirical basis for the development of a novel multimodal composite drug delivery system for anticancer therapy combined with noninvasive MRI capability.

Robust system for the regenerative capture of aqueous pollutants with continuously synthesized and functionalized magnetic nanoparticles

Nowadays, the design of efficient technologies for the detection and separation of environmental pollutants from aqueous solutions continues to be a challenge to the industrial sector. The present work proposes a robust microfluidic system for the continuous, rapid and effective testing of selective capture agents of aqueous pollutants based on the use of magnetic nanoparticles, MNPs. These are found of special interest due to their high specific surface area, easy functionalization and superparamagnetic behavior. In this work, MNPs with an average diameter of 8.8 ± 1.3 nm and amino-functionalization were obtained following a novel continuous synthesis that facilitated the control of the particles properties. The microfluidic capture of Cr(VI) from aqueous solutions was assessed as representative case study; followed by the successful regeneration of loaded MNPs. The obtained results prove the advantages of the proposed system: i) continuous synthesis of functionalized MNPs with rigorous size control, ii) selective and fast capture of the target compound depending on the particle’s functionalization and large surface area, respectively, ii) continuous operation that facilitates process scale-up, iii) easy regeneration of the functional materials, and iv) magnetic separation of MNPs from fluid media if needed. Furthermore, the calculated Cr(VI) maximum uptake is higher than obtained values for non-functionalized MNPs and is in the range of previously reported data for ion exchange resins, with the additional advantages already mentioned. Thus, this work constitutes a step forward in the methodological design of advanced systems with detection or separation purposes and can be extended to a wide variety of pollutants.

Magnetoimpedance Biosensors and Real-Time Healthcare Monitors: Progress, Opportunities, and Challenges.

A small DC magnetic field can induce an enormous response in the impedance of a soft magnetic conductor in various forms of wire, ribbon, and thin film. Also known as the giant magnetoimpedance (GMI) effect, this phenomenon forms the basis for the development of high-performance magnetic biosensors with magnetic field sensitivity down to the picoTesla regime at room temperature. Over the past decade, some state-of-the-art prototypes have become available for trial tests due to continuous efforts to improve the sensitivity of GMI biosensors for the ultrasensitive detection of biological entities and biomagnetic field detection of human activities through the use of magnetic nanoparticles as biomarkers. In this review, we highlight recent advances in the development of GMI biosensors and review medical devices for applications in biomedical diagnostics and healthcare monitoring, including real-time monitoring of respiratory motion in COVID-19 patients at various stages. We also discuss exciting research opportunities and existing challenges that will stimulate further study into ultrasensitive magnetic biosensors and healthcare monitors based on the GMI effect.

Multifunctional magnetic nanoparticles for MRI-guided co-delivery of erlotinib and L-asparaginase to ovarian cancer

The use of magnetic nanoparticles (MNPs) in biomedical applications has been wildly opted due to their unique properties. Here, we designed MNPs loaded with erlotinib (ERL/SPION-Val-PEG) and conjugated them with anti-mucin16 (MUC16) aptamer to introduce new image-guided nanoparticles (NPs) for targeted drug delivery as well as non-invasive magnetic resonance imaging (MRI) contrast agents. Also, the combination of our nanosystem (NS) along with L-Asparaginase (L-ASPN) led to synergistic effects in terms of reducing cell viability in ovarian cancer cells, which could suggest a novel combination therapy. The mean size of our NS was about 63.4 ± 3.4 nm evaluated by DLS analysis and its morphology was confirmed using TEM. Moreover, the functional groups, as well as magnetic properties of our NS, were examined by FT-IR and VSM tests, respectively. The loading efficacy of erlotinib on MNPs was about 80% and its release reached 70.85% over 7 days in the pH value of 5.4. The MR images and flow cytometry results revealed that the cellular uptake of ERL/SPION-Val-PEG-MUC16 NPs in cells with MUC16 overexpression was considerably higher than unarmed NPs. In addition, T2-weight MR images of ovarian cancer-bearing mice indicated significant signal intensity changes at the tumour site 4 h after intravenous injection compared to the non-target MNPs. Our data suggest ERL/SPION-Val-PEG NPs as an image-guided co-drug delivery system for ovarian cancer.

Magnetic/flow controlled continuous size fractionation of magnetic nanoparticles using simulated moving bed chromatography.

The use of magnetic nanoparticles shows a steadily increasing technical importance. Particularly in medical technology disciplines such as cancer treatment, the potential of these special particles is increasing rapidly. Magnetic nanoparticles are particles with a submicron size, and consist mostly of magnetite-containing composites. An important quality parameter of such particles is a particle size distribution as narrow as possible, which can only be obtained to a certain degree by synthesis. Apart from ultracentrifugation, there are so far only methods on an analytical scale to narrow the size distribution as a post-processing step. We present a method based on magnetic chromatography, by which high separation efficiencies at yields of up to 99.9% are achieved. The novel technique is based on a competition between the magnetic interaction of the nanoparticles and the separation matrix, as well as the hydrodynamic forces. Furthermore, the method is extended using a continuous mode, namely simulated moving bed chromatography, to obtain potent space-time yields of up to 2.94g/(L*h). For those reasons, this novel continuous magnetic chromatography method offers high potential for large-scale refinement of magnetic nanoparticles while fulfilling sophisticated quality criteria for high-technology applications.

Folic Acid-Adorned Curcumin-Loaded Iron Oxide Nanoparticles for Cervical Cancer.

Cancer is a deadly disease that has long plagued humans and has become more prevalent in recent years. The common treatment modalities for this disease have always faced many problems and complications, and this has led to the discovery of strategies for cancer diagnosis and treatment. The use of magnetic nanoparticles in the past two decades has had a significant impact on this. One of the objectives of the present study is to introduce the special properties of these nanoparticles and how they are structured to load and transport drugs to tumors. In this study, iron oxide (Fe3O4) nanoparticles with 6 nm sizes were coated with hyperbranched polyglycerol (HPG) and folic acid (FA). The functionalized nanoparticles (10–20 nm) were less likely to aggregate compared to non-functionalized nanoparticles. HPG@Fe3O4 and FA@HPG@Fe3O4 nanoparticles were compared in drug loading procedures with curcumin. HPG@Fe3O4 and FA@HPG@Fe3O4 nanoparticles’ maximal drug-loading capacities were determined to be 82 and 88%, respectively. HeLa cells and mouse L929 fibroblasts treated with nanoparticles took up more FA@HPG@Fe3O4 nanoparticles than HPG@Fe3O4 nanoparticles. The FA@HPG@Fe3O4 nanoparticles produced in the current investigation have potential as anticancer drug delivery systems. For the purpose of diagnosis, incubation of HeLa cells with nanoparticles decreased MRI signal enhancement’s percentage and the largest alteration was observed after incubation with FA@HPG@Fe3O4 nanoparticles.

Magnetic Nanoparticles in Medicine: Progress, Problems, and Advances

The review presents an analysis of the current state of research related to the design, development, and practical application of methods for biomedical radioelectronics and nanomedicine, including the use of magnetic nanoparticles. The important role of rational scientific physical approaches and experimental methods in the design of efficient and safe magnetic nanoparticle-based agents for therapy, controlled targeted drug delivery, and diagnostics, including spatial imaging, is emphasized. Examples of successful practical application of magnetic nanoparticles in medicine based on these methods are given, and an analysis of the main problems and prospects of this area of science is conducted.

Magnetic Fields and Cancer: Epidemiology, Cellular Biology, and Theranostics.

Humans are exposed to a complex mix of man-made electric and magnetic fields (MFs) at many different frequencies, at home and at work. Epidemiological studies indicate that there is a positive relationship between residential/domestic and occupational exposure to extremely low frequency electromagnetic fields and some types of cancer, although some other studies indicate no relationship. In this review, after an introduction on the MF definition and a description of natural/anthropogenic sources, the epidemiology of residential/domestic and occupational exposure to MFs and cancer is reviewed, with reference to leukemia, brain, and breast cancer. The in vivo and in vitro effects of MFs on cancer are reviewed considering both human and animal cells, with particular reference to the involvement of reactive oxygen species (ROS). MF application on cancer diagnostic and therapy (theranostic) are also reviewed by describing the use of different magnetic resonance imaging (MRI) applications for the detection of several cancers. Finally, the use of magnetic nanoparticles is described in terms of treatment of cancer by nanomedical applications for the precise delivery of anticancer drugs, nanosurgery by magnetomechanic methods, and selective killing of cancer cells by magnetic hyperthermia. The supplementary tables provide quantitative data and methodologies in epidemiological and cell biology studies. Although scientists do not generally agree that there is a cause-effect relationship between exposure to MF and cancer, MFs might not be the direct cause of cancer but may contribute to produce ROS and generate oxidative stress, which could trigger or enhance the expression of oncogenes.

Magnetic Nanoparticle-Mediated Heating for Biomedical Applications.

Magnetic nanoparticles, especially superparamagnetic nanoparticles (SPIONs), have attracted tremendous attention for various biomedical applications. Facile synthesis and functionalization together with easy control of the size and shape of SPIONS to customize their unique properties, have made it possible to develop different types of SPIONs tailored for diverse functions/applications. More recently, considerable attention has been paid to the thermal effect of SPIONs for the treatment of diseases like cancer and for nanowarming of cryopreserved/banked cells, tissues, and organs. In this mini-review, recent advances on the magnetic heating effect of SPIONs for magnetothermal therapy and enhancement of cryopreservation of cells, tissues, and organs, are discussed, together with the non-magnetic heating effect (i.e., high Intensity focused ultrasound or HIFU-activated heating) of SPIONs for cancer therapy. Furthermore, challenges facing the use of magnetic nanoparticles in these biomedical applications are presented.

Determination of effective assay parameters on the activity of magnetite cross-linked invertase aggregates by personal glucose meter

The invertase enzyme has been immobilized onto various support materials to enhance operational stability, shelf life, and reusability compared to free ones. Among the immobilization methods, carrier-free immobilization, such as cross-linked enzyme aggregates (CLEAs), attracts attention. However, recovery of the CLEAs from the reaction environment by centrifugation or filtration is a great challenge. The use of magnetic nanoparticles (Fe3O4) can overcome these separation limitations of the aggregates. For this aim, in this study, the surface of magnetite nanoparticles was functionalized with a significant number of free amino groups through silanization reaction. After precipitation of these aggregates and then cross-linking to the functionalized structure, the resulting magnetite cross-linked invertase aggregates (MCLIAs) were obtained, having different enzyme and glutaraldehyde concentrations. Magnetic nanoparticles were characterized by SEM, VSM, and FTIR analysis. The assay parameters, both constructional and experimental ones on the activity of MCLIAs, were practically determined by a personal glucose meter (PGM). The results indicate that magnetite nanoparticles with superparamagnetic behaviour were successfully functionalized with amino groups. The activity results demonstrated that experimental parameters were more effective than constructional parameters. MCLIAs also exhibited maximum activity at pH 5. Furthermore, 30-min incubation time and 35 °C were the best activity assay conditions.

Improved Suzuki\u2013Miyaura reaction conversion efficiency using magnetic nanoparticles and inductive heating

The use of magnetic nanoparticles in C–C coupling reactions enables the facile recovery of the catalyst under environmentally friendly conditions. Herein, the synthesis of Pd/Fe@Fe3O4 nanoparticles by the reduction of Pd2+ and oxidation of Fe on the surface of preformed Fe@Fe3O4 is reported. The nanoparticles were characterized using a variety of analytical techniques (transmission electron microscopy, Mössbauer spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction) to determine their size, structure, and chemical composition. The catalytic efficiency of these nanoparticles in classical Suzuki–Miyaura coupling reactions was investigated. The nanoparticles achieved high catalytic activity with the application of local heating by an alternating magnetic field. An investigation was conducted at identical temperatures to compare global heating with the application of an external magnetic field; magnetic heating demonstrated excellent substrate conversion in lesser time and at a lower temperature. The catalyst could also be recycled and reused three times, with ~ 30% decrease in the substrate conversion, which is most likely due to the agglomeration of the Pd nanoparticles or poisoning of the Pd catalyst. This approach, which takes advantage of the catalytic activity and magnetic susceptibility of magnetic nanoparticles, can be applied to several organic transformations to improve their efficiency.Graphical abstract

An integrated magneto-opto-fluidic biosensor for rapid on-chip assay of respiratory viruses of livestock.

Respiratory disease is one of the most important causes of economic loss in swine production. In the USA, porcine reproductive and respiratory syndrome virus (PRRSV) and influenza A virus (IAV) are currently the top two primary viruses causing swine respiratory diseases. The commonly used PCR-based virus detection methods require virus extraction, nucleic acid purification, and detection, which are relatively time-consuming and expensive. This work reports an integrated magneto-opto-fluidic (iMOF) platform, in which antibody functionalized magnetic nanoparticles (MNPs) can enable efficient enrichment of multiple swine respiratory viruses and a photonic crystal (PC) biosensor can transduce the amount of captured MNP-virus nanoparticles to the change of their reflection signatures. Owing to the high refractive index of Fe2O3 MNPs, the use of MNPs can significantly enhance the PC sensor output. The proof-of-concept validation involves using antibody-functionalized MNPs to recognize IAV and PRRSV and transferring the formed MNP-virus conjugates onto the surface of the PC biosensors to quantify these viruses. The iMOF platform offers a high sensitivity of 3.5 TCID50 mL-1 and 5.9 TCID50 mL-1 for detecting IAV and PRRSV, respectively, and a rapid turnaround within one hour, including the MNP-virus conjugation, enrichment, and detection. The on-chip virus platform has a great potential for in-field surveillance of viral infections.

Magnetic properties of textured ferrocomposite consisting of immobilized superparamagnetic nanoparticles.

Wide use of magnetic nanoparticles in modern technologies and biomedical applications requires reliable theoretical models capable of predicting physical properties. Solidification of a ferroparticle suspension under the action of permanent magnetic field allows us to obtain a ferrocomposite, characterized by some orientational texture of the nanoparticle easy magnetization axes. The static magnetic response of this ferrocomposite differs from that of the parent magnetic suspension due to "freezing" of nanoparticle translational and rotational degrees of freedom. Here the superparamagnetic fluctuations of the nanoparticle magnetic moments play a key role in the formation of the ferrocomposite magnetic response depending on the degree of orientational ordering, obtained during synthesis of a ferrocomposite. With the help of statistical mechanics we calculate the magnetization and the initial magnetic susceptibility of the textured ferrocomposite for various temperatures and magnetic field strengths. The easy axis texturing leads to a significant increase of the magnetic properties, and the effect intensifies with the growth of nanoparticle magnetocrystalline anisotropy. Theoretical predictions are supported by Monte Carlo simulations. The obtained results evidence that the texturing of a ferroparticle suspension and transforming it into a textured ferrocomposite are a real way to enhance the magnetic response of these magnetic soft materials.

Magnetic nanoparticles: A novel adjunct for dentistry

Magneticnanoparticles(MNPs), a type of nanocarriers have attracted attention in the area of drug delivery with wide diagnostic and therapeutic applications mainly due its unique physicochemical properties and its ability to function at both molecular and cellular level.The other property of MNPs that have contributed to its popularization is target specific cellular action that reduces the systemic cytotoxicity of the compound. Hence in recent years nanoparticles and magnetic forces are used in dentistry to deliver medications to prevent and treat dental diseases. The MNPs based therapies are very effective against bacterial and fungal pathogens which are resistant to conventional antibiotic therapy. In the area of esthetic dentistry the concept of MNPs has improved the dental material translucency and wear resistance. The use of MNPs in various form of dental drug delivery system has reduced the incidence of dental caries formation and endodontic and periodontal pathologies. The addition of MNPs in dental composite material and dental adhesive has inhibited the biofilm formation. In this chapter, bird’s eye focus on the applications of magnetic nanoparticles in dentistry, its biocompatibility and safety is summarized.

Magnetic nanoparticles coated with carboxylate-terminated carbosilane dendrons as a reusable and green approach to extract/purify proteins

Extraction/purification of proteins, at both analytical and industrial levels, is a limiting step that usually requires the use of organic solvents and involves tedious work and a high cost. This work proposes a more sustainable alternative based on the use of magnetic nanoparticles (MNPs) coated with carboxylate-terminated carbosilane dendrons. MNPs coated with first- and second-generation carbosilane dendrons and bare MNPs were employed for the extraction of proteins with different molecular weights and charges. Interaction of proteins with MNPs significantly varied with the pH, the protein, and the dendron generation (different sizes and number of charges in the periphery). Optimal dendron:protein molar ratios and suitable conditions for disrupting interactions after protein extraction were also researched. Second-generation dendron-coated MNPs showed 100% retention capability for all proteins when using acidic conditions. They were reused without losing magnetism or interaction capacity after a disruption of protein-dendron interactions with 0.2% SDS at 100 °C for 10 min. The capacity of dendron-coated MNPs was successfully applied to the recovery/purification of proteins from two food by-products, olive seeds and cheese whey.Graphical abstract

Fabrication of chitosan-coated mixed spinel ferrite integrated with graphene oxide (GO) for magnetic extraction of viral RNA for potential detection of SARS-CoV-2.

Genetic variants of the COVID-19 causative virus have been arising and circulating globally. In many countries, especially in developing ones with a huge population, vaccination has become one of the major challenges. SARS-CoV-2 variants’ fast transmission rate has an upsurge in the COVID cases, leading to more stress on health systems. In the current COVID-19 scenario, there is the requirement of more adequate diagnostic approaches to check the COVID-19 spread. Out of many diagnostic approaches, a magnetic nanoparticle-based reverse transcription polymerase chain reaction could be nontrivial. The use of magnetic nanoparticles is to separate nucleic acid of SARS-CoV-2 from the patient samples and apply for SARS-CoV-2 detection in an easy and more effective way. Herein, the magnetic nanoparticles are synthesized using the solgel autocombustion methods and then successfully coated with biopolymer (chitosan) using ultrasonication. Chitosan-coated nanoparticles are successfully integrated into the graphene oxide sheets to introduce carboxyl groups. Crystallite size calculation, morphological and magnetic studies of synthesized magnetic nanoparticles, and multifunctional magnetic nanoparticles are done using XRD, SEM, TEM, and VSM, respectively. Besides, the potentiality of the fabricated nanocomposites in RNA extraction protocol is also discussed with schematic representation.