Magnetic Nanoparticles in Biology and Medicine: Past, Present, and Future Trends

Starch-Coated Magnetic Iron Oxide Nanoparticles for Affinity Purification of Recombinant Proteins

Starch-coated magnetic iron oxide nanoparticles have been synthesized by a simple, fast, and cost-effective co-precipitation method with cornstarch as a stabilizing agent. The structural and magnetic characteristics of the synthesized material have been studied by transmission electron microscopy, Mössbauer spectroscopy, and vibrating sample magnetometry. The nature of bonds between ferrihydrite nanoparticles and a starch shell has been examined by Fourier transform infrared spectroscopy. The data on the magnetic response of the prepared composite particles have been obtained by magnetic measurements. The determined magnetic characteristics make the synthesized material a good candidate for use in magnetic separation. Starch-coated magnetic iron oxide nanoparticles have been tested as an affinity sorbent for one-step purification of several recombinant proteins (cardiac troponin I, survivin, and melanoma inhibitory activity protein) bearing the maltose-binding protein as an auxiliary fragment. It has been shown that, due to the highly specific binding of this fragment to the starch shell, the target fusion protein is selectively immobilized on magnetic nanoparticles and eluted with the maltose solution. The excellent efficiency of column-free purification, high binding capacity of the sorbent (100–500 µg of a recombinant protein per milligram of starch-coated magnetic iron oxide nanoparticles), and reusability of the obtained material have been demonstrated.

Recent advances in the application of magnetic bio-polymers as catalysts in multicomponent reactions

Magnetic nanoparticles have attracted significant attention due to their high surface area and superparamagnetic properties. Bio-polymers composed of polysaccharides including alginate, cellulose, glucose, dextrin, chitosan, and starch can be immobilized on magnetic nanoparticles. Bio-polymers can be obtained from natural sources, such as plants, tunicates, algae, and bacteria. Bio-polymers obtained from natural sources have attracted attention due to their various properties including efficient functional groups, non-toxicity, low cost, availability, and biocompatibility. According to the targets of "green chemistry", the application of bio-polymers is effective in reducing pollution. Furthermore, they are excellent agents for the functionalization of magnetic nanoparticles to yield nanomagnetic bio-polymers, which can be applied as recoverable and eco-friendly catalysts in multicomponent reactions.

Parallel Multichannel Assessment of Rotationally Manipulated Magnetic Nanoparticles

Background

Rotational manipulation of chains or clusters of magnetic nanoparticles (MNPs) offers a means for directed translation and payload delivery that should be explored for clinical use. Multiple MNP types are available, yet few studies have performed side-by-side comparisons to evaluate characteristics such as velocity, movement at a distance, and capacity for drug conveyance or dispersion.

Purpose

Our goal was to design, build, and study an electric device allowing simultaneous, multichannel testing (e.g., racing) of MNPs in response to a rotating magnetic field. We would then select the "best" MNP and use it with optimized device settings, to transport an unbound therapeutic agent.

Methods

A magnetomotive system was constructed, with a Helmholtz pair of coils on either side of a single perpendicular coil, on top of which was placed an acrylic tray having multiple parallel lanes. Five different MNPs were tested: graphene-coated cobalt MNPs (TurboBeads™), nickel nanorods, gold-iron alloy MNPs, gold-coated Fe3O4 MNPs, and uncoated Fe3O4 MNPs. Velocities were determined in response to varying magnetic field frequencies (5-200 Hz) and heights (0-18 cm). Velocities were normalized to account for minor lane differences. Doxorubicin was chosen as the therapeutic agent, assayed using a CLARIOstar Plus microplate reader.

Results

The MMS generated a maximal MNP velocity of 0.9 cm/s. All MNPs encountered a "critical" frequency at 20-30 Hz. Nickel nanorods had the optimal response based on tray height and were then shown to enable unbound doxorubicin dispersion along 10.5 cm in <30 sec.

Conclusion

A rotating magnetic field can be conveniently generated using a three-coil electromagnetic device, and used to induce rotational and translational movement of MNP aggregates over mesoscale distances. The responses of various MNPs can be compared side-by-side using multichannel acrylic trays to assess suitability for drug delivery, highlighting their potential for further in vivo applications.

Long-Term Clearance and Biodistribution of Magnetic Nanoparticles Assessed by AC Biosusceptometry

Once administered in an organism, the physiological parameters of magnetic nanoparticles (MNPs) must be addressed, as well as their possible interactions and retention and elimination profiles. Alternating current biosusceptometry (ACB) is a biomagnetic detection system used to detect and quantify MNPs. The aims of this study were to evaluate the biodistribution and clearance of MNPs profiles through long-time in vivo analysis and determine the elimination time carried out by the association between the ACB system and MnFe₂O₄ nanoparticles. The liver, lung, spleen, kidneys, and heart and a blood sample were collected for biodistribution analysis and, for elimination analysis, and over 60 days. During the period analyzed, the animal’s feces were also collectedd. It was possible to notice a higher uptake by the liver and the spleen due to their characteristics of retention and uptake. In 60 days, we observed an absence of MNPs in the spleen and a significant decay in the liver. We also determined the MNPs’ half-life through the liver and the spleen elimination. The data indicated a concentration decay profile over the 60 days, which suggests that, in addition to elimination via feces, there is an endogenous mechanism of metabolization or possible agglomeration of MNPs, resulting in loss of ACB signal intensity.

Preparation of NiFe2O4@MIL-101(Fe)/GO as a novel nanocarrier and investigation of its antimicrobial properties

In this research, we have investigated a novel magnetic nanocomposite including NiFe2O4@MIL-101(Fe)/GO for the delivery of the antibiotic tetracycline (TC). Moreover, the antibacterial activity of NiFe2O4@MIL-101(Fe)/GO, NiFe2O4@MIL-101(Fe)/GO/TC and pure TC was evaluated by agar well diffusion and minimum inhibitory concentration (MIC) methods on both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. In addition, the cytotoxicity of NiFe2O4@MIL-101(Fe)/GO/TC on HeLa cells was determined by an MTT assay which showed good results. The structure of the prepared nanocarrier was investigated by various spectroscopic techniques such as Fourier-transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Brunauer-Emmett-Teller (BET), and thermal gravimetric analysis (TGA). The results of this study showed that 98% of the TC was loaded on the synthesized nanocomposite. Drug release occurred at pH: 7.4 (phosphate buffer saline) and pH: 5.0 (acetate buffer) within 3 days, resulting in 77% and 85% release of the drug, respectively.

An update on the applications and characteristics of magnetic iron oxide nanoparticles for drug delivery

INTRODUCTION

In the field of drug delivery, controlling the release of therapeutic substances at localized targets has become a primary focus of medical research, especially in the field of cancer treatment. Magnetic nanoparticles are one of the most promising drug carriers thanks to their biocompatibility and (super)paramagnetic properties. These properties allow for the combination between imaging modalities and specific release of drugs at target sites using either local stimulus (i.e. pH, conjugation of biomarkers, …) or external stimulus (i.e. external magnetic field).

AREAS COVERED

This review provides an update on recent advances with the development of targeted drug delivery systems based on magnetic nanoparticles (MNPs). This overview focuses on active targeting strategies and systems combining both imaging and therapeutic modalities (i.e. theranostics). If most of the examples concern the particular case of cancer therapy, the possibility of using MNPs for other medical applications is also discussed.

EXPERT OPINION

The development of clinically relevant drug delivery systems based on magnetic nanoparticles is driven by advantages stemming from their remarkable properties (i.e. easy preparation, facile chemical functionalization, biocompatibility, low toxicity and superior magnetic responsiveness). This literature review shows that drug carriers based on magnetic nanoparticles can be efficiently used for the controlled release of drug at targeted locations mediated by various stimuli. Advances in the field should lead to the implementation of such systems into clinical trials, especially systems enabling drug tracking in the body.

The Yin and Yang of epigenetics in the field of nanoparticles

Nanoparticles (NPs) have become a very exciting research avenue, with multitudinous applications in various fields, including the biomedical one, whereby they have been gaining considerable interest as drug carriers able to increase bioavailability, therapeutic efficiency and specificity of drugs. Epigenetics, a complex network of molecular mechanisms involved in gene expression regulation, play a key role in mediating the effect of environmental factors on organisms and in the etiology of several diseases (e.g., cancers, neurological disorders and cardiovascular diseases). For many of these diseases, epigenetic therapies have been proposed, whose application is however limited by the toxicity of epigenetic drugs. In this review, we will analyze two aspects of epigenetics in the field of NPs: the first is the role that epigenetics play in mediating nanotoxicity, and the second is the possibility of using NPs for delivery of "epi-drugs" to overcome their limitations. We aim to stimulate discussion among specialists, specifically on the potential contribution of epigenetics to the field of NPs, and to inspire newcomers to this exciting technology.

Improving Antibacterial Efficiency of Curcumin in Magnetic Polymeric Nanocomposites

In recent years, resistance to chemical antibiotics, as well as their side effects, has caused a necessity to utilize natural substances and herbal components with antibacterial effects. Curcumin, the major substance of Curcuma longa’s rhizome, was used as an antibacterial agent since ancient times. This work aimed to formulate a novel nanocomposite for the delivery of curcumin to overcome orthodox drugs resistance against bacteria and improve its efficacy. To fabricate targeting nanocomposites, first, Fe3O4 nanoparticles were synthesized followed by coating the obtained nanoparticles using sodium alginate containing curcumin. A 2 by 3 factorial design was tailored to predict the optimum formulation of nanocomposites. Characterization of nanocomposites including particle size, polydispersity index (PDI), zeta potential, entrapment efficiency, and drug loading was performed. The optimum formulation was analyzed by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier-transformed infrared spectroscopy (FT-IR), and in vitro release study at different pHs. Finally, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of samples against seven common bacteria were determined. Results showed that the optimized formulation contained 400 nm particles with the PDI and zeta potentials of 0.4 and − 58 mV, respectively. The optimized formulation with 70% entrapment efficiency reduced the MIC value 2 to 4 times in comparison with pure curcumin. Results also showed that polymer and drug concentrations can significantly affect entrapment efficiency. In conclusion, the current investigation demonstrated that this magnetic nanocomposite can be applied for the delivery of curcumin.

Graphical abstract

Serum Albumin for Magnetic Nanoparticles Coating

Magnetic nanoparticles (MNPs) have great potential in biochemistry and medical science. In particular, iron oxide nanoparticles have demonstrated a promising effect in various biomedical applications due to their high magnetic properties, large surface area, stability, and easy functionalization. However, colloidal stability, biocompatibility, and potential toxicity of MNPs in physiological environments are crucial for their in vivo application. In this context, many research articles focused on the possible procedures for MNPs coating to improve their physic-chemical and biological properties. This review highlights one viable fabrication strategy of biocompatible iron oxide nanoparticles using human serum albumin (HSA). HSA is mainly a transport protein with many functions in various fundamental processes. As it is one of the most abundant plasma proteins, not a single drug in the blood passes without its strength test. It influences the stability, pharmacokinetics, and biodistribution of different drug-delivery systems by binding or forming its protein corona on the surface. The development of albumin-based drug carriers is gaining increasing importance in the targeted delivery of cancer therapy. Considering this, HSA is a highly potential candidate for nanoparticles coating and theranostics area and can provide biocompatibility, prolonged blood circulation, and possibly resolve the drug-resistance cancer problem.

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.

Drug Delivery Systems and Strategies to Overcome the Barriers of Brain

The transport of drugs to the central nervous system is the most challenging task for conventional drug delivery systems. Reduced permeability of drugs through the blood-brain barrier is a major hurdle in delivering drugs to the brain. Hence, various strategies for improving drug delivery through the blood-brain barrier are currently being explored. Novel drug delivery systems (NDDS) offer several advantages, including high chemical and biological stability, suitability for both hydrophobic and hydrophilic drugs, and can be administered through different routes. Furthermore, the conjugation of suitable ligands with these carriers tend to potentiate targeting to the endothelium of the brain and could facilitate the internalization of drugs through endocytosis. Further, the intranasal route has also shown potential, as a promising alternate route, for the delivery of drugs to the brain. This can deliver the drugs directly to the brain through the olfactory pathway. In recent years, several advancements have been made to target and overcome the barriers of the brain. This article deals with a detailed overview of the diverse strategies and delivery systems to overcome the barriers of the brain for effective delivery of drugs.

Biocompatible Nanomaterials as an Emerging Technology in Reproductive Health; a Focus on the Male

A growing body of research has confirmed that nanoparticle (NP) systems can enhance delivery of therapeutic and imaging agents as well as prevent potentially damaging systemic exposure to these agents by modifying the kinetics of their release. With a wide choice of NP materials possessing different properties and surface modification options with unique targeting agents, bespoke nanosystems have been developed for applications varying from cancer therapeutics and genetic modification to cell imaging. Although there remain many challenges for the clinical application of nanoparticles, including toxicity within the reproductive system, some of these may be overcome with the recent development of biodegradable nanoparticles that offer increased biocompatibility. In recognition of this potential, this review seeks to present recent NP research with a focus on the exciting possibilities posed by the application of biocompatible nanomaterials within the fields of male reproductive medicine, health, and research.

Biogenic Synthesis of Iron Oxide Nanoparticles Using Enterococcus faecalis: Adsorption of Hexavalent Chromium from Aqueous Solution and In Vitro Cytotoxicity Analysis

The biological synthesis of nanoparticles is emerging as a potential method for nanoparticle synthesis due to its non-toxicity and simplicity. In the present study, a bacterium resistant to heavy metals was isolated from a metal-contaminated site and we aimed to report the synthesis of Fe3O4 nanoparticles via co-precipitation using bacterial exopolysaccharides (EPS) derived from Enterococcus faecalis_RMSN6 strains. A three-variable Box-Behnken design was used for determining the optimal conditions of the Fe3O4 NPs synthesis process. The synthesized Fe3O4 NPs were thoroughly characterized through multiple analytical techniques such as XRD, UV-Visible spectroscopy, FTIR spectroscopy and finally SEM analysis to understand the surface morphology. Fe3O4 NPs were then probed for the Cr(VI) ion adsorption studies. The important parameters such as optimization of initial concentration of Cr(VI) ions, effects of contact time, pH of the solution and contact time on quantity of Cr(VI) adsorbed were studied in detail. The maximum adsorption capacity of the nanoparticles was found to be 98.03 mg/g. The nanoparticles could retain up to 73% of their efficiency of chromium removal for up to 5 cycles. Additionally, prepared Fe3O4 NPs in the concentration were subjected to cytotoxicity studies using an MTT assay. The investigations using Fe3O4 NPs displayed a substantial dose-dependent effect on the A594 cells. The research elucidates that the Fe3O4 NPs synthesized from EPS of E. faecalis_RMSN6 can be used for the removal of heavy metal contaminants from wastewater.

Particulate Air Pollution and Risk of Neuropsychiatric Outcomes. What We Breathe, Swallow, and Put on Our Skin Matters

We appraise newly accumulated evidence of the impact of particle pollution on the brain, the portals of entry, the neural damage mechanisms, and ultimately the neurological and psychiatric outcomes statistically associated with exposures. PM pollution comes from natural and anthropogenic sources such as fossil fuel combustion, engineered nanoparticles (NP ≤ 100 nm), wildfires, and wood burning. We are all constantly exposed during normal daily activities to some level of particle pollution of various sizes-PM_2.5 (≤2.5 µm), ultrafine PM (UFP ≤ 100 nm), or NPs. Inhalation, ingestion, and dermal absorption are key portals of entry. Selected literature provides context for the US Environmental Protection Agency (US EPA) ambient air quality standards, the conclusions of an Independent Particulate Matter Review Panel, the importance of internal combustion emissions, and evidence suggesting UFPs/NPs cross biological barriers and reach the brain. NPs produce oxidative stress and neuroinflammation, neurovascular unit, mitochondrial, endoplasmic reticulum and DNA damage, protein aggregation and misfolding, and other effects. Exposure to ambient PM_2.5 concentrations at or below current US standards can increase the risk for TIAs, ischemic and hemorrhagic stroke, cognitive deficits, dementia, and Alzheimer's and Parkinson's diseases. Residing in a highly polluted megacity is associated with Alzheimer neuropathology hallmarks in 99.5% of residents between 11 months and ≤40 y. PD risk and aggravation are linked to air pollution and exposure to diesel exhaust increases ALS risk. Overall, the literature supports that particle pollution contributes to targeted neurological and psychiatric outcomes and highlights the complexity of the pathophysiologic mechanisms and the marked differences in pollution profiles inducing neural damage. Factors such as emission source intensity, genetics, nutrition, comorbidities, and others also play a role. PM_2.5 is a threat for neurological and psychiatric diseases. Thus, future research should address specifically the potential role of UFPs/NPs in inducing neural damage.

Genotoxic Potential of Nanoparticles: Structural and Functional Modifications in DNA

The rapid advancement of nanotechnology enhances the production of different nanoparticles that meet the demand of various fields like biomedical sciences, industrial, material sciences and biotechnology, etc. This technological development increases the chances of nanoparticles exposure to human beings, which can threaten their health. It is well known that various cellular processes (transcription, translation, and replication during cell proliferation, cell cycle, cell differentiation) in which genetic materials (DNA and RNA) are involved play a vital role to maintain any structural and functional modification into it. When nanoparticles come into the vicinity of the cellular system, chances of uptake become high due to their small size. This cellular uptake of nanoparticles enhances its interaction with DNA, leading to structural and functional modification (DNA damage/repair, DNA methylation) into the DNA. These modifications exhibit adverse effects on the cellular system, consequently showing its inadvertent effect on human health. Therefore, in the present study, an attempt has been made to elucidate the genotoxic mechanism of nanoparticles in the context of structural and functional modifications of DNA.

Dynamic Susceptibility of Ferrofluids: The Numerical Algorithm for the Inverse Problem of Magnetic Granulometry

The size-dependent properties of magnetic nanoparticles (MNP) are the major characteristics, determining MNP application in modern technologies and bio-medical techniques. Direct measurements of the nanosized particles, involved in intensive Brownian motion, are very complicated; so the correct mathematical methods for the experimental data processing enable to successfully predict the properties of MNP suspensions. In the present paper, we describe the fast numerical algorithm allowing to get the distribution over the relaxation time of MNP magnetic moments in ferrofluids. The algorithm is based on numerical fitting of the experimentally measured frequency spectra of the initial dynamic magnetic susceptibility. The efficiency of the algorithm in the solution of the inverse problem of magnetic granulometry is substantiated by the computer experiments for mono- and bi-fractional ferrofluids.

The Direct Effect of Magnetic Tape® on Pain and Lower-Extremity Blood Flow in Subjects with Low-Back Pain: A Randomized Clinical Trial

Low-back pain has a high impact on the world population, and solutions are in demand. The behavior of specific physiological processes has been modified using magnetic fields, whether for pain relief, bone consolidation, or improvement of vascularization. The use of tape with magnetic properties could help in these cases. A double-blind randomized clinical trial was designed to use Magnetic Tape® versus placebo Kinesio tape. Blood flow variables were evaluated using pulsed power Doppler ultrasound. Resistance index, pulsatility index, systolic velocity, and diastolic velocity were measured. The pressure pain threshold was measured using algometry in 22 subjects. The results reveal significant differences between the groups for the pulsation index variable (8.06 [5.16, 20.16] in Magnetic Tape® versus 5.50 [4.56, 6.64] in Kinesio tape) and lower (0.98 [0.92, 1.02] for Magnetic Tape® versus 0.99 [0.95, 1.01] for Kinesio tape) in the resistance index variable. The pressure pain threshold variable presented significant differences at multiple levels. The application of Magnetic Tape® causes immediate effects on blood flow and pain and could be a technique of choice for pain modulation. Further studies would be necessary.