Magnetic iron oxide nanoparticles for drug delivery: applications and characteristics

Advances in the therapeutic delivery and applications of functionalized Pluronics: A critical review

Pluronic (PEO-PPO-PEO) block copolymers can form nano-sized micelles with a structure composed of a hydrophobic PPO core and hydrophilic PEO shell layer. Pluronics are U.S. Food and Drug Administration approved polymers, which are widely used for solubilization of drugs and their delivery, gene/therapeutic delivery, diagnostics, and tissue engineering applications due to their non-ionic properties, non-toxicity, micelle forming ability, excellent biocompatibility and biodegradability. Although Pluronics have been employed as drug carrier systems for several decades, numerous issues such as rapid dissolution, shorter residence time in biological media, fast clearance and weak mechanical strength have hindered their efficacy. Pluronics have been functionalized with pH-sensitive, biological-responsive moieties, antibodies, aptamers, folic acid, drugs, different nanoparticles, and photo/thermo-responsive hydrogels. These functionalization strategies enable Pluronics to act as stimuli responsive and targeted drug delivery vehicles. Moreover, Pluronics have emerged in nano-emulsion formulations and have been utilized to improve the properties of cubosomes, dendrimers and nano-sheets, including their biocompatibility and aqueous solubility. Functionalization of Pluronics results in the significant improvement of target specificity, loading capacity, biocompatibility of nanoparticles and stimuli responsive hydrogels for the promising delivery of a range of drugs. Therefore, this review presents an overview of all advancements (from the last 15 years) in functionalized Pluronics, providing a valuable tool for industry and academia in order to optimize their use in drug or therapeutic delivery, in addition to several other biomedical applications.

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.

Current Treatments and New Possible Complementary Therapies for Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is one of the deadliest gynaecological malignancies. The late diagnosis is frequent due to the absence of specific symptomatology and the molecular complexity of the disease, which includes a high angiogenesis potential. The first-line treatment is based on optimal debulking surgery following chemotherapy with platinum/gemcitabine and taxane compounds. During the last years, anti-angiogenic therapy and poly adenosine diphosphate-ribose polymerases (PARP)-inhibitors were introduced in therapeutic schemes. Several studies have shown that these drugs increase the progression-free survival and overall survival of patients with ovarian cancer, but the identification of patients who have the greatest benefits is still under investigation. In the present review, we discuss about the molecular characteristics of the disease, the recent evidence of approved treatments and the new possible complementary approaches, focusing on drug repurposing, non-coding RNAs, and nanomedicine as a new method for drug delivery.

Aminopropylimidazole as an Advantageous Coating in the Synthesis of Functionalized Magnetite Nanoparticles

Implementing new methods to prepare magnetite nanoparticles with a covered or uncovered surface has been, and still is, a significant challenge. In this work, we describe a very clear and effortless way for the preparation of magnetite nanoparticles using two types of bases, namely: 1-(3-aminopropyl)imidazole and sodium hydroxide. Fourier transform infrared spectroscopy (FTIR) served as a tool for the structural investigation of the as-prepared magnetite nanoparticles. The morphology of the samples was investigated using Transmission Electron Microscopy (TEM). Comprehensive high-resolution X-ray photoelectron spectroscopy investigations (XPS) were applied as an effective tool for analyzing the composition of the various types of magnetic nanoparticles. Further polymer linkage was accomplished with poly(benzofuran-co-arylacetic acid) on the amino-functionalized surface of aminopropylimidazole-containing magnetic nanoparticles. The findings are promising for biomedicine, catalysis, and nanotechnology applications.

Recent development for biomedical applications of magnetic nanoparticles

In recent decades, the use of engineered nanoparticles has been increasing in various sectors, including biomedicine, diagnosis, water treatment, and environmental remediation leading to significant public concerns. Among these nanoparticles, magnetic nanoparticles (MNPs) have gained many attentions in medicine, pharmacology, drug delivery system, molecular imaging, and bio-sensing due to their various properties. In addition, various studies have reviewed MNPs main applications in the biomedical engineering area with intense progress and recent achievements. Nanoparticles, especially the magnetic nanoparticles, have recently been confirmed with excellent antiviral activity against different viruses, including SARS-CoV-2(Covid-19) and their recent development against Covid-19 also has also been discussed. This review aims to highlight the recent development of the magnetic nanoparticles and their biomedical applications such as diagnosis of diseases, molecular imaging, hyperthermia, bio-sensing, gene therapy, drug delivery and the diagnosis of Covid-19.

Nanoparticle Systems for Cancer Phototherapy: An Overview

Photodynamic therapy (PDT) and photothermal therapy (PTT) are photo-mediated treatments with different mechanisms of action that can be addressed for cancer treatment. Both phototherapies are highly successful and barely or non-invasive types of treatment that have gained attention in the past few years. The death of cancer cells because of the application of these therapies is caused by the formation of reactive oxygen species, that leads to oxidative stress for the case of photodynamic therapy and the generation of heat for the case of photothermal therapies. The advancement of nanotechnology allowed significant benefit to these therapies using nanoparticles, allowing both tuning of the process and an increase of effectiveness. The encapsulation of drugs, development of the most different organic and inorganic nanoparticles as well as the possibility of surfaces' functionalization are some strategies used to combine phototherapy and nanotechnology, with the aim of an effective treatment with minimal side effects. This article presents an overview on the use of nanostructures in association with phototherapy, in the view of cancer treatment.

Latest trends on photodynamic disinfection of Gram-negative bacteria: photosensitizer's structure and delivery systems

Antimicrobial resistance is threatening to overshadow last century's medical advances. Etiological agents of previously eradicated infectious diseases are now resurgent as multidrug-resistant strains, especially for Gram-negative strains. Finding new therapeutic solutions is a real challenge for our society. In this framework, Photodynamic Antimicrobial ChemoTherapy relies on the generation of toxic reactive oxygen species in the presence of light, oxygen, and a photosensitizer molecule. The use of reactive oxygen species is common for disinfection processes, using chemical agents, such as chlorine and hydrogen peroxide, and as they do not have a specific molecular target, it decreases the potential of tolerance to the antimicrobial treatment. However, light-driven generated reactive species result in an interesting alternative, as reactive species generation can be easily tuned with light irradiation and several PSs are known for their low environmental impact. Over the past few years, this topic has been thoroughly studied, exploring strategies based on single-molecule PSs (tetrapyrrolic compounds, dipyrrinate derivatives, metal complexes, etc.) or on conjunction with delivery systems. The present work describes some of the most relevant advances of the last 6 years, focusing on photosensitizers design, formulation, and potentiation, aiming for the disinfection of Gram-negative bacteria.

Nanoparticle-Guided Brain Drug Delivery: Expanding the Therapeutic Approach to Neurodegenerative Diseases

Neurodegenerative diseases (NDs) represent a heterogeneous group of aging-related disorders featured by progressive impairment of motor and/or cognitive functions, often accompanied by psychiatric disorders. NDs are denoted as 'protein misfolding' diseases or proteinopathies, and are classified according to their known genetic mechanisms and/or the main protein involved in disease onset and progression. Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD) are included under this nosographic umbrella, sharing histopathologically salient features, including deposition of insoluble proteins, activation of glial cells, loss of neuronal cells and synaptic connectivity. To date, there are no effective cures or disease-modifying therapies for these NDs. Several compounds have not shown efficacy in clinical trials, since they generally fail to cross the blood-brain barrier (BBB), a tightly packed layer of endothelial cells that greatly limits the brain internalization of endogenous substances. By engineering materials of a size usually within 1-100 nm, nanotechnology offers an alternative approach for promising and innovative therapeutic solutions in NDs. Nanoparticles can cross the BBB and release active molecules at target sites in the brain, minimizing side effects. This review focuses on the state-of-the-art of nanoengineered delivery systems for brain targeting in the treatment of AD, PD and HD.

Immobilization of L-asparaginase on magnetic nanoparticles: Kinetics and functional characterization and applications

L-asparaginase shows great potential as a food enzyme to reduce acrylamide formation in fried and baked products. But for food applications, enzymes must be stable at high temperatures and have higher catalytic efficiency. These desirable characteristics are conferred by the immobilization of enzymes on a suitable matrix. The present study aimed to immobilize the L-asparaginase enzyme on magnetic nanoparticles to reduce acrylamide content in the food system. Immobilized preparations were characterized using SEM, TEM, FTIR, UV-spectrometry, and XRD diffraction analyses. These nanoparticles enhanced the thermal stability of the enzyme up to four-fold at 70 °C compared to the free enzyme. Kinetic parameters exhibited an increase in V_max, K_m, and catalytic efficiency by ~ 38% than the free counterpart. The immobilized preparations were reusable for up to five cycles. Moreover, their application in the pre-treatment coupled with blanching of potato chips led to a significant reduction (greater than 95%) of acrylamide formation.

Synthesis of Pore-Size-Tunable Mesoporous Silica Nanoparticles by Simultaneous Sol-Gel and Radical Polymerization to Enhance Silibinin Dissolution

BACKGROUND

Silibinin (SBN), a major active constituent of milk thistle seeds, exhibits numerous pharmacological activities. However, its oral bioavailability is low due to poor water solubility. This study aimed to develop a new synthetic approach for tuning the pore characteristics of mesoporous silica nanoparticles (MSNs) intended for the oral delivery of SBN. In addition, the effects of the pore diameter of MSNs on the loading capacity and the release profile of SBN were investigated.

METHODS

The present study was performed at Shiraz University of Medical Sciences, Shiraz, Iran, in 2019. This synthesis method shares the features of the simultaneous free-radical polymerization of methyl methacrylate and the sol-gel reaction of the silica precursor at the n-heptane/water interface. SBN was loaded onto MSNs, the in vitro release was determined, and the radical scavenging activities were compared between various pH values using the analysis of variance.

RESULTS

According to the Brunauer-Emmett-Teller protocol, the pore sizes were well-tuned in the range of 2 to 7 nm with a large specific surface area (600-1200 m²/g). Dynamic light scattering results showed that different volume ratios of n-heptane/water resulted in different sizes, ranging from 25 to 100 nm. Interestingly, high SBN loading (13% w/w) and the sustained release of the total drug over 12 hours were achieved in the phosphate buffer (pH=6.8). Moreover, the antioxidant activity of SBN was well preserved in acidic gastric pH.

CONCLUSION

Well-tuned pores of MSNs provided a proper substrate, and thus, enhanced SBN loading and oral dissolution and preserved its antioxidant activity. Nevertheless, further in vitro and in vivo investigations are needed.

2D Quantitative Imaging of Magnetic Nanoparticles by an AC Biosusceptometry Based Scanning Approach and Inverse Problem

The use of magnetic nanoparticles (MNPs) in biomedical applications requires the quantitative knowledge of their quantitative distribution within the body. AC Biosusceptometry (ACB) is a biomagnetic technique recently employed to detect MNPs in vivo by measuring the MNPs response when exposed to an alternate magnetic field. The ACB technique presents some interesting characteristics: non-invasiveness, low operational cost, high portability, and no need for magnetic shielding. ACB conventional methods until now provided only qualitative information about the MNPs’ mapping in small animals. We present a theoretical model and experimentally demonstrate the feasibility of ACB reconstructing 2D quantitative images of MNPs’ distributions. We employed an ACB single-channel scanning approach, measuring at 361 sensor positions, to reconstruct MNPs’ spatial distributions. For this, we established a discrete forward problem and solved the ACB system’s inverse problem. Thus, we were able to determine the positions and quantities of MNPs in a field of view of 5×5×1 cm3 with good precision and accuracy. The results show the ACB system’s capabilities to reconstruct the quantitative spatial distribution of MNPs with a spatial resolution better than 1 cm, and a sensitivity of 1.17 mg of MNPs fixed in gypsum. These results show the system’s potential for biomedical application of MNPs in several studies, for example, electrochemical-functionalized MNPs for cancer cell targeting, quantitative sensing, and possibly in vivo imaging.

Co-modification with MSC membrane and PDA prevents Fe3O4-induced pulmonary toxicity in mice via AMPK-ULK1 axis

Fe₃O₄ nanoparticles are widely used in the diagnosis and treatment of diseases due to their superparamagnetism, but their toxicity in vivo, which can result in apoptosis or autophagy, cannot be ignored. It has been reported that polydopamine (PDA) modification can reduce the toxicity of Fe₃O₄ and increase its biocompatibility. However, more research is warranted to further improve the modification method. We therefore developed a new method to coat Fe₃O₄@PDA nanoparticles with the mesenchymal stem cell membrane (MSCM) and evaluated the toxicity of the modified particles in the lungs of mice. We found that the MSCM modification significantly reduced lung injury induced by Fe₃O₄ particles in mice. Compared with Fe₃O₄@PDA nanoparticles, co-modification with MSCM and PDA significantly reduced autophagy and apoptosis in mouse lung tissue, and reduced activation of autophagy mediated by the AMPK-ULK1 pathway axis. Thus, co-modification with MSCM and PDA prevents Fe₃O₄-induced pulmonary toxicity in mice by inhibiting autophagy, apoptosis, and oxidative stress.

Layered Double Hydroxides as a Drug Delivery Vehicle for S-Allyl-Mercapto-Cysteine (SAMC)

The intercalations of anionic molecules and drugs in layered double hydroxides (LDHs) have been intensively investigated in recent years. Due to their properties, such as versatility in chemical composition, good biocompatibility, high density and protection of loaded drugs, LDHs seem very promising nanosized systems for drug delivery. In this work, we report the intercalation of S-allyl-mercapto-cysteine (SAMC), which is a component of garlic that is well-known for its anti-tumor properties, inside ZnAl-LDH (hereafter LDH) nanostructured crystals. In order to investigate the efficacy of the intercalation and drug delivery of SAMC, the intercalated compounds were characterized using X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The increase in the interlayer distance of LDH from 8.9 Å, typical of the nitrate phase, to 13.9 Å indicated the intercalation of SAMC, which was also confirmed using FT-IR spectra. Indeed, compared to that of the pristine LDH precursor, the spectrum of LDH-SAMC was richly structured in the fingerprint region below 1300 cm−1, whose peaks corresponded to those of the functional groups in the SAMC molecular anion. The LDH-SAMC empirical formula, obtained from UV-Vis spectrophotometry and thermogravimetric analysis, was [Zn0.67Al0.33(OH)2]SAMC0.15(NO3)0.18·0.6H2O. The morphology of the sample was investigated using SEM: LDH-SAMC exhibited a more irregular size and shape of the flake-like crystals in comparison with the pristine LDH, with a reduction in the average crystallite size from 3 µm to about 2 µm. In vitro drug release studies were performed in a phosphate buffer solution at pH 7.2 and 37 °C and were analyzed using UV-Vis spectrophotometry. The SAMC release from LDH-SAMC was initially characterized by a burst effect in the first four hours, during which, 32% of the SAMC is released. Subsequently, the release percentage increased at a slower rate until 42% after 48 h; then it stabilized at 43% and remained constant for the remaining period of the investigation. The LDH-SAMC complex that was developed in this study showed the improved efficacy of the action of SAMC in reducing the invasive capacity of a human hepatoma cell line.

Layer-by-Layer Fabrication of Hydrogel Microsystems for Controlled Drug Delivery From Untethered Microrobots

Targeted drug delivery from untethered microrobots is a topic of major interest in current biomedical research. The possibility to load smart materials able to administer active principles on remotely in vivo guidable microdevices constitutes one of the most attractive opportunities to overcome the drawbacks of classical untargeted delivery methodologies. Hydrogels, in particular, are ideal candidates as drug-carrying materials due to their biocompatibility, low cost, and ease of manufacturing. On the other hand, these polymers suffer from poor control over release rate and overall released amount. Starting from these premises, the present article demonstrates the possibility to tune the release of hydrogels applied on magnetically steerable microrobots by fabricating microsystems via layer-by-layer self-assembly. By doing this, the diffusion of chemicals from the hydrogel layers to the external environment can be optimized and the phenomenon of burst release can be strongly limited. The microrobotic platforms employed to transport the hydrogel active material are fabricated by employing 3D printing in combination with wet metallization and present a gold layer on their surface to enhance biocompatibility. The maneuverability of microdevices coated with both thin and thick multilayers is investigated, individuating optimized parameters for efficient actuation.

Advances in Magnetic Nanoparticles Engineering for Biomedical Applications-A Review

Magnetic iron oxide nanoparticles (MNPs) have been developed and applied for a broad range of biomedical applications, such as diagnostic imaging, magnetic fluid hyperthermia, targeted drug delivery, gene therapy and tissue repair. As one key element, reproducible synthesis routes of MNPs are capable of controlling and adjusting structure, size, shape and magnetic properties are mandatory. In this review, we discuss advanced methods for engineering and utilizing MNPs, such as continuous synthesis approaches using microtechnologies and the biosynthesis of magnetosomes, biotechnological synthesized iron oxide nanoparticles from bacteria. We compare the technologies and resulting MNPs with conventional synthetic routes. Prominent biomedical applications of the MNPs such as diagnostic imaging, magnetic fluid hyperthermia, targeted drug delivery and magnetic actuation in micro/nanorobots will be presented.

Striking Back against Fungal Infections: The Utilization of Nanosystems for Antifungal Strategies

Fungal infections have become a major health concern, given that invasive infections by Candida, Cryptococcus, and Aspergillus species have led to millions of mortalities. Conventional antifungal drugs including polyenes, echinocandins, azoles, allylamins, and antimetabolites have been used for decades, but their limitations include off-target toxicity, drug-resistance, poor water solubility, low bioavailability, and weak tissue penetration, which cannot be ignored. These drawbacks have led to the emergence of novel antifungal therapies. In this review, we discuss the nanosystems that are currently utilized for drug delivery and the application of antifungal therapies.

Iron Oxide Nanoparticles in Regenerative Medicine and Tissue Engineering

In recent years, many promising nanotechnological approaches to biomedical research have been developed in order to increase implementation of regenerative medicine and tissue engineering in clinical practice. In the meantime, the use of nanomaterials for the regeneration of diseased or injured tissues is considered advantageous in most areas of medicine. In particular, for the treatment of cardiovascular, osteochondral and neurological defects, but also for the recovery of functions of other organs such as kidney, liver, pancreas, bladder, urethra and for wound healing, nanomaterials are increasingly being developed that serve as scaffolds, mimic the extracellular matrix and promote adhesion or differentiation of cells. This review focuses on the latest developments in regenerative medicine, in which iron oxide nanoparticles (IONPs) play a crucial role for tissue engineering and cell therapy. IONPs are not only enabling the use of non-invasive observation methods to monitor the therapy, but can also accelerate and enhance regeneration, either thanks to their inherent magnetic properties or by functionalization with bioactive or therapeutic compounds, such as drugs, enzymes and growth factors. In addition, the presence of magnetic fields can direct IONP-labeled cells specifically to the site of action or induce cell differentiation into a specific cell type through mechanotransduction.

Preparation of Titanium Oxide-Based Nanoparticles Modified with D-(+)-Mannose and Investigation of their Properties As A Potential Drug Carrier

Titanium oxide nanoparticles modified with D-(+)-mannose were obtained. In the process of their formation, they were conjugated with an active substance (tadalafil). The physicochemical properties of the obtained products were assessed, and the size and electrokinetic potential were determined using a dynamic light scattering technique. X-ray diffractometry was applied in order to define the crystalline properties, and Fourier-transform infrared spectroscopy was used to confirm the formation of the desired products. It was possible to obtain TiO2 coated with D-(+)-mannose. The average size of nanoparticles was between 230 and 268 nm. The release of the active substance from the product over a time period of three hours was assessed against the reference material, which was not modified by D-(+)-mannose. The results indicate that covering titanium oxide nanoparticles with the modifying substance favours a slower rate of release for the active substance, which is the desired effect from a pharmacological point of view. The releasing of active substance from modified products was even 68% slower than that from the reference product. These modified titanium oxides are promising materials that may have found an application as drug carriers.

Graphic Abstract

Anti-Cancer Nanopowders and MAPLE-Fabricated Thin Films Based on SPIONs Surface Modified with Paclitaxel Loaded β-Cyclodextrin

Globally, cancer is the second most common cause of death, and Europe accounts for almost 25% of the global cancer burden, although its people make up only 10% of the world’s population. Conventional systemically administered anti-cancer drugs come with important drawbacks such as inefficiency due to poor bioavailability and improper biodistribution, severe side effects associated with low therapeutic indices, and the development of multidrug resistance. Therefore, smart nano-engineered targeted drug-delivery systems with tailored pharmacokinetics and biodistribution which can selectively deliver anti-cancer agents directly to the tumor site are the solution to most difficulties encountered with conventional therapeutic tools. Here, we report on the synthesis, physicochemical characterization, and in vitro evaluation of biocompatibility and anti-tumor activity of novel magnetically targetable SPIONs based on magnetite (Fe₃O₄) nanoparticles’ surface modified with β-cyclodextrin (CD) and paclitaxel (PTX)–guest–host inclusion complexes (Fe₃O₄@β-CD/PTX). Both pristine Fe₃O₄@β-CD nanopowders and PTX-loaded thin films fabricated by MAPLE technique were investigated. Pristine Fe₃O₄@β-CD and Fe₃O₄@β-CD/PTX thin films were physicochemically characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermal analysis, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The biocompatibility of bare magnetic nanocomposite thin films was evaluated by MTT cell viability assay on a normal 3T3 osteoblast cell line culture and by measuring the level of NO in the culture medium. No significant modifications, neither in cell viability nor in NO level, could be observed, thereby demonstrating the excellent biocompatibility of the SPIONs thin films. Inverted phase-contrast microscopy showed no evident adverse effect on the morphology of normal osteoblasts. On the other hand, Fe₃O₄@β-CD/PTX films decreased the cell viability of the MG-63 osteosarcoma cell line by 85%, demonstrating excellent anti-tumor activity. The obtained results recommend these magnetic hybrid films as promising candidates for future delivery, and hyperthermia applications in cancer treatment.

Green biosynthesis, characterization, and cytotoxic effect of magnetic iron nanoparticles using Brassica Oleracea var capitata sub var rubra (red cabbage) aqueous peel extract

The green method of nanoparticle synthesis, which is an environment and living-friendly method, is an updated subject that has appeared as an alternative to conventional methods such as physical and chemical synthesis. In this presented study, the green synthesis of magnetic iron oxide nanoparticles (IONPs) from iron (III) chloride by using Brassica oleracea var. capitata sub.var. rubra aqueous peel extract has been reported. The prepared IONPs were characterized with fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-VIS), zeta potential, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The cytotoxic effects of IONPs on MCF-7 breast cancer cell line were studied by MTT assay, and migrative effect of its were carried out by the wound healing assay. It was found that the mean particle size of IONPs was 675 ± 25 nm, and the polydispersity index was 0.265 PDI. It was also determined that these nanoparticles had an anti-proliferative impact on the MCF-7 breast cancer cell line depending on the dosage. Characterization results support the successful synthesis of nanoparticles, and the dose-dependent cytotoxic effects of nanoparticles on MCF-7 cells also make it a potential chemotherapeutic agent for breast cancer treatment.

Toxicity of Nanoparticles in Biomedical Application: Nanotoxicology

Nanoparticles are of great importance in development and research because of their application in industries and biomedicine. The development of nanoparticles requires proper knowledge of their fabrication, interaction, release, distribution, target, compatibility, and functions. This review presents a comprehensive update on nanoparticles' toxic effects, the factors underlying their toxicity, and the mechanisms by which toxicity is induced. Recent studies have found that nanoparticles may cause serious health effects when exposed to the body through ingestion, inhalation, and skin contact without caution. The extent to which toxicity is induced depends on some properties, including the nature and size of the nanoparticle, the surface area, shape, aspect ratio, surface coating, crystallinity, dissolution, and agglomeration. In all, the general mechanisms by which it causes toxicity lie on its capability to initiate the formation of reactive species, cytotoxicity, genotoxicity, and neurotoxicity, among others.

Magnetic nanoparticles (Fe3O4 NPs) fabricated composite microgels and their applications in different fields

This article encircles the research progress of Fe3O4 NPs loaded composite microgel particles. Preparation methodologies, properties and applications of Fe3O4 NPs loaded composite microgel particles are elaborated here. The effect of different factors on the stability and tunable properties of Fe3O4 NPs loaded composite microgel particles was also investigated in detail. These composite particles have exceptional magnetic properties that make them demanding composite nano-formulation in different fields. Applications of these composite microgel particles in different fields as micro-reactor, drug delivery vehicles, and in adsorption and catalysis have also been elaborated in detail. These composite microgel particles can easily be recovered from the reaction mixture by applying an external magnet due to the presence of fabricated Fe3O4 NPs.

Nanotechnology-Based Strategies to Overcome Current Barriers in Gene Delivery

Nanomaterials are currently being developed for the specific cell/tissue/organ delivery of genetic material. Nanomaterials are considered as non-viral vectors for gene therapy use. However, there are several requirements for developing a device small enough to become an efficient gene-delivery tool. Considering that the non-viral vectors tested so far show very low efficiency of gene delivery, there is a need to develop nanotechnology-based strategies to overcome current barriers in gene delivery. Selected nanostructures can incorporate several genetic materials, such as plasmid DNA, mRNA, and siRNA. In the field of nanotechnologies, there are still some limitations yet to be resolved for their use as gene delivery systems, such as potential toxicity and low transfection efficiency. Undeniably, novel properties at the nanoscale are essential to overcome these limitations. In this paper, we will explore the latest advances in nanotechnology in the gene delivery field.

Magnetic systems for cancer immunotherapy

Immunotherapy is a rapidly developing area of cancer treatment due to its higher specificity and potential for greater efficacy than traditional therapies. Immune cell modulation through the administration of drugs, proteins, and cells can enhance antitumoral responses through pathways that may be otherwise inhibited in the presence of immunosuppressive tumors. Magnetic systems offer several advantages for improving the performance of immunotherapies, including increased spatiotemporal control over transport, release, and dosing of immunomodulatory drugs within the body, resulting in reduced off-target effects and improved efficacy. Compared to alternative methods for stimulating drug release such as light and pH, magnetic systems enable several distinct methods for programming immune responses. First, we discuss how magnetic hyperthermia can stimulate immune cells and trigger thermoresponsive drug release. Second, we summarize how magnetically targeted delivery of drug carriers can increase the accumulation of drugs in target sites. Third, we review how biomaterials can undergo magnetically driven structural changes to enable remote release of encapsulated drugs. Fourth, we describe the use of magnetic particles for targeted interactions with cellular receptors for promoting antitumor activity. Finally, we discuss translational considerations of these systems, such as toxicity, clinical compatibility, and future opportunities for improving cancer treatment.

The Role of Exosomes and Their Cargos in the Mechanism, Diagnosis, and Treatment of Atrial Fibrillation

Atrial fibrillation (AF) is the most common persistent arrhythmia, but the mechanism of AF has not been fully elucidated, and existing approaches to diagnosis and treatment face limitations. Recently, exosomes have attracted considerable interest in AF research due to their high stability, specificity and cell-targeting ability. The aim of this review is to summarize recent literature, analyze the advantages and limitations of exosomes, and to provide new ideas for their use in understanding the mechanism and improving the diagnosis and treatment of AF.

Synthesis and characterization of magnetic nanocomposite for in vitro evaluation of irinotecan using human cell lines

In this study, magnetic O-carboxymethyl chitosan (MOCC) nanocomposite was synthesized and characterized as a drug delivery system for loading the anticancer drug irinotecan (CPT-11). To increase the drug loading capacity, MOCC was synthesized by linking the carboxyl group functionally to chitosan. Also, several critical factors such as concentration, the dose of MOCC, and contact time for optimum drug loading condition were investigated. The loading capacity of CPT-11 onto MOCC was calculated as 5.6 mg/g, and the loaded drug concentration was calculated as 0.04787 mM at pH value of 5. Besides, the cytotoxic properties of MOCC, CPT- 11 loaded MOCC (MOCC-CPT-11), and free CPT-11 were studied on glioblastoma multiforme cell lines, including U87 and U373. According to the results, the MOCC-CPT-11 showed at least as toxic effect as free CPT-11 even at very low concentrations, while the MOCC showed slight toxicity (cell viability of 96% to 78%) on U373 cell lines at all concentrations and for 24 h and 48 h incubation times. Moreover, the results showed that the MOCC indicated significant toxicity in increasing concentrations and incubation times, and the MOCC-CPT-11 is as toxic as free CPT-11 on U87 cells at all concentrations and incubation times.

Interactions of Chemically Synthesized Ferrihydrite Nanoparticles with Human Serum Transferrin: Insights from Fluorescence Spectroscopic Studies

Human serum transferrin (HST) is a glycoprotein involved in iron transport that may be a candidate for functionalized nanoparticles to bind and target cancer cells. In this study, the effects of the simple and doped with cobalt (Co) and copper (Cu) ferrihydrite nanoparticles (Fh-NPs, Cu-Fh-NPs, and Co-Fh-NPs) were studied by spectroscopic and molecular approaches. Fluorescence spectroscopy revealed a static quenching mechanism for all three types of Fh-NPs. All Fh-NPs interacted with HST with low affinity, and the binding was driven by hydrogen bonding and van der Waals forces for simple Fh-NPs and by hydrophobic interactions for Cu-Fh-NPs and Co-Fh-NPs binding, respectively. Of all samples, simple Fh-NPs bound the most to the HST binding site. Fluorescence resonance energy transfer (FRET) allowed the efficient determination of the energy transfer between HST and NPs and the distance at which the transfer takes place and confirmed the mechanism of quenching. The denaturation of the HST is an endothermic process, both in the case of apo HST and HST in the presence of the three types of Fh-NPs. Molecular docking studies revealed that Fh binds with a low affinity to HST (K_a = 9.17 × 10³ M⁻¹) in accord with the fluorescence results, where the interaction between simple Fh-NPs and HST was described by a binding constant of 9.54 × 10³ M⁻¹.

Effect of Different Physical Cross-Linkers on Drug Release from Hydrogel Layers Coated on Magnetically Steerable 3D-Printed Microdevices

In the last few decades, the introduction of microrobotics has drastically changed the way medicine will be approached in the future. The development of untethered steerable microdevices able to operate in vivo inside the human body allows a high localization of the therapeutical action, thus limiting invasiveness and possible medical complications. This approach results are particularly useful in drug delivery, where it is highly beneficial to administer the drug of choice exclusively to the target organ to avoid overdosage and side effects. In this context, drug releasing layers can be loaded on magnetically moveable platforms that can be guided toward the target organ to perform highly targeted release. In the present paper, we evaluate the possible application of alginate hydrogel layers on moveable platforms manufactured by coupling additive manufacturing with wet metallization. Such alginate layers are reticulated using three different physical crosslinkers: Ca, Zn or Mn. Their effect on drug release kinetics and on device functionality is evaluated. In the case of alginate reticulated using Mn, the strongly pH dependent behavior of the resulting hydrogel is evaluated as a possible way to introduce a triggered release functionality on the devices.

Iron Oxide Nanoparticles in Bioimaging - An Immune Perspective

Iron oxide nanoparticles (IONPs) bear big hopes in nanomedicine due to their (potential) applications in tumor therapy, drug delivery or bioimaging. However, as foreign entities, such particles may be recognized by the immune system and, thus, lead to inflammation, hypersensitivity or anaphylactic shock. In addition, an overload with iron is known to cause oxidative stress. In this short review, we summarize the biological effects of such particles with a major focus on IONP-formulations used for bioimaging purposes and their effects on the human immune system. We conclude that especially the characteristics of the particles (size, shape, surface charge, coating, etc.) as well as the presence of bystander substances, such as bacterial endotoxin are important factors determining the resulting biological and immunological effects of IONPs. Further studies are needed in order to establish clear structure-activity relationships.

The Use of Iron Oxide Nanoparticles to Reprogram Macrophage Responses and the Immunological Tumor Microenvironment

The synthesis and functionalization of iron oxide nanoparticles (IONPs) is versatile, which has enhanced the interest in studying them as theranostic agents over recent years. As IONPs begin to be used for different biomedical applications, it is important to know how they affect the immune system and its different cell types, especially their interaction with the macrophages that are involved in their clearance. How immune cells respond to therapeutic interventions can condition the systemic and local tissue response, and hence, the final therapeutic outcome. Thus, it is fundamental to understand the effects that IONPs have on the immune response, especially in cancer immunotherapy. The biological effects of IONPs may be the result of intrinsic features of their iron oxide core, inducing reactive oxygen species (ROS) and modulating intracellular redox and iron metabolism. Alternatively, their effects are driven by the nanoparticle coating, for example, through cell membrane receptor engagement. Indeed, exploiting these properties of IONPs could lead to the development of innovative therapies. In this review, after a presentation of the elements that make up the tumor immunological microenvironment, we will review and discuss what is currently known about the immunomodulatory mechanisms triggered by IONPs, mainly focusing on macrophage polarization and reprogramming. Consequently, we will discuss the implications of these findings in the context of plausible therapeutic scenarios for cancer immunotherapy.

The Effect of pH and Viscosity on Magnetophoretic Separation of Iron Oxide Nanoparticles

Magnetic nanoparticles (MNPs) are used for magnetophoresis-based separation processes in various biomedical and engineering applications. Essential requirements are the colloidal stability of the MNPs and the ability to be separated even in low magnetic field gradients. Bare iron oxide nanoparticles (BIONs) with a diameter of 9.2 nm are synthesized via coprecipitation, exhibiting a high saturation magnetization of 70.84 Am2 kg−1 and no remanence. In our study, zeta potential, dynamic light scattering (DLS), and sedimentation analysis show that the aggregation behavior of BIONs is influenced by pH and viscosity. Small aggregate clusters are formed with either low or high pH values or increased viscosity. Regarding magnetophoresis-based separation, a higher viscosity leads to lower magnetophoretic velocities, similar to how small aggregates do. Additionally, cooperative magnetophoresis, the joint motion of strongly interacting particles, affects the separation of the BIONs, too. Our study emphasizes the effect of pH and viscosity on the physicochemical characteristics of MNPs, resulting in different aggregation behavior. Particularly, for high viscous working media in downstream processing and medicine, respectively, the viscosity should be taken into account, as it will affect particle migration.

Application of iron/barium ferrite/carbon-coated iron nanocrystal composites in transcatheter arterial chemoembolization of hepatocellular carcinoma

Transcatheter arterial chemoembolization (TACE) has been widely used in clinical practice as a first-line treatment for unresectable hepatocellular carcinoma (HCC). However, the current therapeuticeffect of TACE is far from satisfactory and thus requires further improvement. TACE combined with multifunctional magnetic particles may be a promising approach for the treatment of HCC. In this study, we designed a new magnetic drug carrier system consisting of micron-sized iron powder, barium ferrite (BaFe₁₂O₁₉), and carbon-coated iron nanocrystals (CCINs). CCINs possess properties, such as high drug loading and sustained release. BaFe₁₂O₁₉ could attract both CCINs and iron powder to form larger clusters after magnetization. Altogether, the triple therapeutic effects of chemotherapeutic enhancement, embolization, and thermal ablation could be realized herein. Further experiments indicate that the system has a high drug-loading capacity, good controlled-release effect, and no significant cytotoxicity. Under the action of a medium-frequency magnetic induction device, the magnetic induction temperature could reach 43 °C in one min while the maximum temperature of 70.8 °C could be reached in 2.5 h. Overall, this new carrier system displayed excellent antitumor effects in a mouse model. Our findings demonstrate the great application prospects of this system in TACE for HCC.

Cell surface nucleolin as active bait for nanomedicine in cancer therapy: a promising option

Conventional chemotherapy used against cancer is mostly limited due to their non-targeted nature, affecting normal tissue and causing undesirable toxic effects to the affected tissue. With the aim of improving these treatments both therapeutically and in terms of their safety, numerous studies are currently being carried out using nanoparticles (NPs) as a vector combining tumor targeting and carrying therapeutic tools. In this context, it appears that nucleolin, a molecule over-expressed on the surface of tumor cells, is an interesting therapeutic target. Several ligands, antagonists of nucleolin of various origins, such as AS1411, the F3 peptide and the multivalent pseudopeptide N6L have been developed and studied as therapeutic tools against cancer. Over the last ten years or so, numerous studies have been published demonstrating that these antagonists can be used as tumor targeting agents with NPs from various origins. Focusing on nucleolin ligands, the aim of this article is to review the literature recently published or under experimentation in our research team to evaluate the efficacy and future development of these tools as anti-tumor agents.

AC/DC magnetic device for safe medical use of potentially harmful magnetic nanocarriers

Continuing our previous research work on a drug delivery system based on combined AC/DC magnetic fields, we have developed a prototype AC/DC magnetic syringe device for stimulation of drug release from drug carriers, with the options of injecting/removing drug carriers. The porous Fe₃O₄ carrier, in a dose-dependent manner, causes acute oxidative damage and reduces the viability of differentiated SH-SY5Y human neuroblastoma cells, indicating the necessity for its removal once it reaches the therapeutic concentration at the target tissue. The working mechanism of the device consists of three simple steps. First, direct injection of the drug adsorbed on the surface of a carrier via a needle inserted into the targeted area. The second step is stimulation of drug release using a combination of AC magnetic field (a coil magnetised needle with AC current) and permanent magnets (DC magnetic lens outside of the body), and the third step is removal of the drug carriers from the injected area after the completion of drug release by magnetising the tip of the needle with DC current. Removing the drug carriers allows us to avoid possible acute and long term side effects of the drug carriers in the patient's body, as well as any potential response of the body to the drug carriers.

Chitosan Functionalized Magnetic Nanoparticles to Provide Neural Regeneration and Recovery after Experimental Model Induced Peripheral Nerve Injury

(1) Background: Peripheral nerve injuries have a great impact on a patient's quality of life and a generally poor outcome regarding functional recovery. Lately, studies have focused on different types of nanoparticles and various natural substances for the treatment of peripheral nerve injuries. This is the case of chitosan, a natural compound from the crustaceans' exoskeleton. The present study proposes to combine chitosan benefic properties to the nanoparticles' ability to transport different substances to specific locations and evaluate the effects of magnetic nanoparticles functionalized with chitosan (CMNPs) on peripheral nerve injuries' rehabilitation by using an in vivo experimental model. (2) Methods: CMNPs treatment was administrated daily, orally, for 21 days to rats subjected to right sciatic nerve lesion and compared to the control group (no treatment) by analyzing the sciatic functional index, pain level, body weight, serum nerve growth factor levels and histology, TEM and EDX analysis at different times during the study. (3) Results: Animals treated with CMNPs had a statistically significant functional outcome compared to the control group regarding: sciatic functional index, pain-like behavior, total body weight, which were confirmed by the histological and TEM images. (4) Conclusions: The results of the study suggest that CMNPs appear to be a promising treatment method for peripheral nerve injuries.

Development of a composite film fabricated from carboxymethyl chitosan and magnetite nanoparticles for pH-responsive bioactive agent release

Development of a biocompatible film enabling stimuli-responsive bioactive agent delivery has a high practical value for food and pharmaceutical applications. In this study, we generate a composite film, using the solution casting approach, from carboxymethyl chitosan (CMC) and magnetite nanoparticles (MNPs). The structures and properties of CMC, MNPs, and the generated film are characterized by using various characterization techniques, including Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, x-ray diffraction spectroscopy, and scanning electron microscopy. With the use of doxorubicin (DOX) as a model agent, the percentage of cumulative release of DOX from the agent-loaded film is found to be increased from 55% to 62% when the pH of the surrounding medium changes from 7.4 to 5.0. Our film warrants further development and optimization as a carrier to mediate pH-responsive bioactive agent release.

Mechanism of nanotoxicity in Chlorella vulgaris exposed to zinc and iron oxide

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Growth kinetics of C. vulgaris is influenced by NPs exposure.

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NPs exposure influence proline, carotenoid, activity of SOD, CAT and LDH.

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NPs exposure disintegrate cellular membrane.

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Zinc and iron oxide NPs are more toxic to C. vulgaris compared to bulk counterpart.

Usage of nanoparticle in various products has increased tremendously in the recent past. Toxicity of these nanoparticles can have a huge impact on aquatic ecosystem. Algae are the ideal organism of the aquatic ecosystem to understand the toxicity impact of nanoparticles. The present study focuses on the toxicity evaluation of zinc oxide (ZnO) and iron oxide (Fe₂O₃) nanoparticles towards freshwater microalgae, Chlorella vulgaris. The dose dependent growth retardation in Chlorella vulgaris is observed under ZnO and Fe₂O₃ nanoparticles and nanoform attributed more toxicity than their bulk counterparts. The IC₅₀ values of ZnO and Fe₂O₃ nanoparticles was reported at 0.258 mg L⁻¹ and 12.99 mg L^-1 whereas, for the bulk-form, it was 1.255 mgL^-1 and 17.88 mg L⁻¹, respectively. The significant decline in chlorophyll content and increase in proline content, activity of superoxide dismutase and catalase, indicated the stressful physiological state of microalgae. An increased lactate dehydrogenase level in treated samples suggested membrane disintegration by ZnO and Fe₂O₃ nanoparticles. Compound microscopy, scanning electron microscopy and transmission electron microscopy confirm cell entrapment, deposition of nanoparticles on the cell surface and disintegration of algal cell wall. Higher toxicity of nanoform in comparison to bulk chemistry is a point of concern.

Recent Developments in Nanomedicine for Pediatric Cancer

Cancer is the second biggest cause of death in children in the US. With the development of chemotherapy, there has been a substantial increase in the overall survival rate in the last 30 years. However, the overall mortality rate in children with cancer remains 25%, and many survivors experience a decline in overall quality of life and long-term adverse effects caused by treatments. Although cancer cells share common characteristics, pediatric cancers are different from adult cancers in their prevalence, mutation load, and drug response. Therefore, there is an urgent unmet need to develop therapeutic approaches specifically designed for children with cancer. Nanotechnology can potentially overcome the deficiencies of conventional methods of administering chemotherapy and ultimately improve clinical outcomes. The nanoparticle-based drug delivery systems can decrease the toxicity of therapy, provide a sustained or controlled drug release, improve the pharmacokinetic properties of loading contents, and achieve a targeted drug delivery with achievable modifications. Furthermore, therapeutic approaches based on combining nanoformulated drugs with novel immunotherapeutic agents are emerging. In this review, we discussed the recently developed nanotechnology-based strategies for treating blood and solid pediatric cancers.

Ultrasmall iron oxide nanoparticles cisplatin (IV) prodrug nanoconjugate: ICP-MS based strategies to evaluate the formation and drug delivery capabilities in single cells

Ultrasmall iron oxide nanoparticles (<10 nm) were explored here as nanotransporters of cis-diamminetetrachloroplatinum (IV) (a cisplatin prodrug) in cellular models. The coating of the particles containing reactive carboxylic acid groups enabled the formation of a stable conjugate between the prodrug and the nanoparticles using one pot reaction. The nanoconjugate was characterized by different techniques exhibiting diameters of about 6.6 ± 1.0 nm. The use of a hyphenated strategy based on high performance liquid chromatography (HPLC) coupled to inductively coupled plasma mass spectrometry (ICP-MS) permitted the quantitative evaluation of Fe and Pt in the nanoconjugate. Furthermore, the cellular uptake of the synthetic nanoconjugate was explored by single cell-ICP-MS (SC-ICP) which was used for the first time in this type of studies. The experiments in A2780 and A2780cis, sensitive and resistant ovarian cancer cell models respectively, revealed intracellular platinum concentrations of 12 fg/cell and 4 fg/cell, respectively which were 4-fold higher with respect to the uptake of cisplatin in both models. Intracellular drug release from the nanoconjugate was proved by measuring DNA platination in the same cells. In this case, levels of about 250 ng Pt/mg DNA were observed, about 5-fold higher when the nanoconjugate was used in comparison to cisplatin. Furthermore, the differences between the two lines turned to be significantly smaller than in the case of using cisplatin. The quantitative analytical tools developed here provided essential information required to fully characterize the developed nanoplatforms particularly important to overcome drug resistance.

Cellular SPION Uptake and Toxicity in Various Head and Neck Cancer Cell Lines

Superparamagnetic iron oxide nanoparticles (SPIONs) feature distinct magnetic properties that make them useful and effective tools for various diagnostic, therapeutic and theranostic applications. In particular, their use in magnetic drug targeting (MDT) promises to be an effective approach for the treatment of various diseases such as cancer. At the cellular level, SPION uptake, along with SPION-mediated toxicity, represents the most important prerequisite for successful application. Thus, the present study determines SPION uptake, toxicity and biocompatibility in human head and neck tumor cell lines of the tongue, pharynx and salivary gland. Using magnetic susceptibility measurements, microscopy, atomic emission spectroscopy, flow cytometry, and plasma coagulation, we analyzed the magnetic properties, cellular uptake and biocompatibility of two different SPION types in the presence and absence of external magnetic fields. Incubation of cells with lauric acid and human serum albumin-coated nanoparticles (SPION^LA-HSA) resulted in substantial particle uptake with low cytotoxicity. In contrast, uptake of lauric acid-coated nanoparticles (SPION^LA) was substantially increased but accompanied by higher toxicity. The presence of an external magnetic field significantly increased cellular uptake of both particles, although cytotoxicity was not significantly increased in any of the cell lines. SPIONs coated with lauric acid and/or human serum albumin show different patterns of uptake and toxicity in response to an external magnetic field. Consequently, the results indicate the potential use of SPIONs as vehicles for MDT in head and neck cancer.

Stimuli-Responsive Iron Oxide Nanotheranostics: A Versatile and Powerful Approach for Cancer Therapy

Recent advancements in unravelling elements of cancer biology involved in disease progression and treatment resistance have highlighted the need for a holistic approach to effectively tackle cancer. Stimuli-responsive nanotheranostics based on iron oxide nanoparticles are an emerging class of versatile nanomedicines with powerful capabilities to "seek, sense, and attack" multiple components of solid tumors. In this work, the rationale for using iron oxide nanoparticles and the basic physical principles that impact their function in biomedical applications are reviewed. Subsequently, recent advances in the integration of iron oxide nanoparticles with various stimulus mechanisms to facilitate the development of stimuli-responsive nanotheranostics for application in cancer therapy are summarized. The integration of an iron oxide core with various surface coating mechanisms results in the generation of hybrid nanoconstructs with capabilities to codeliver a wide variety of highly potent anticancer therapeutics and immune modulators. Finally, emerging future directions and considerations for their clinical translation are touched upon.

Intestinal and hepatic effects of iron oxide nanoparticles

Iron oxide nanoparticles gain increasing attention due to their broad industrial use. However, safety concerns exist since their effects on human cells are still under investigation. The presence of iron oxide nanoparticles in the food pigment E172 has been shown recently. Here, we studied four iron oxide nanoparticles, one food pigment E172 and the ionic control FeSO₄ regarding dissolution in biological media, uptake and transport, and cellular effects in vitro in human intestinal Caco-2 and HepaRG hepatocarcinoma cells. The iron oxide nanoparticles passed the gastrointestinal passage without dissolution and reached the intestine in the form of particles. Minor uptake was seen into Caco-2 cells but almost no transport to the basolateral site was detected for any of the tested particles. HepaRG cells showed higher particle uptake. Caco-2 cells showed no alterations in reactive oxygen species production, apoptosis, or mitochondrial membrane potential, whereas two particles induced apoptosis in HepaRG cells, and one altered mitochondrial membrane potential at non-cytotoxic concentrations. No correlation between physicochemical particle characteristics and cellular effects was observed, thus emphasizing the need for case-by-case assessment of iron oxide nanoparticles.