Magnetic Nanoparticles as MRI Contrast Agents

Development of a two-probe competitive enzyme-linked immunosorbent assay for porcine epidemic diarrhea virus based on magnetic nanoparticles

Porcine epidemic diarrhea (PED) causes significant economic losses to the pig farming industry worldwide and currently lacks an effective vaccine. Multiple detection assays and protein purification methods use magnetic nanoparticles due to their biocompatibility, high specific surface area, and solution suspension properties. In this study, a two-probe competitive ELISA based on magnetic nanoparticles for detecting PEDV N protein was developed. MNPs-N and McAb-HRP probes were prepared and the procedure was optimized to identify the ideal reaction conditions. Compared to other methods, the developed method shortens the detection time to 50 min. The coefficient of variation (CV) for intra- and inter-lot replicates was less than 10 %, with reproducibility. The coincidence rate with commercial kits is 93.07 %, making this method reliable and suitable for PED immune monitoring and diagnostics.

Unveiling the differences: A comprehensive multi-technique analysis of hard and soft nanoparticles

The characterization of nanoparticles has become increasingly important due to their wide-ranging applications in fields such as biomedicine and drug delivery. Nanoparticles (NPs) have emerged as promising candidates for drug delivery systems due to their unique physicochemical properties, which enable them to interact with biological systems at the molecular level. Among these, soft nanocarriers, such as niosomes, and hard nanocarriers, such as Iron Oxide Nanoparticles (IONPs), offer distinct advantages for targeted therapy and diagnostics. This study provides a comprehensive, multi-disciplinary evaluation of two distinct types of nanoparticles: soft nanocarriers (niosomes, NVs) and hard nanocarriers (IONPs), by examining their physicochemical properties, cellular uptake, and cytotoxicity profiles. This comparative analysis seeks to highlight the different behaviour of soft and hard nanoparticles in drug delivery applications, with a particular focus on the impact of surface modifications. The addition of chitosan to sample NVsB not only resulted in an increase in particle dimensions but also shifted the ζ-potential to positive values which could enhance the interactions with cell membranes, improving cellular uptake. As desired, the obtained ζ-potential value of NVsB-Chit was comparable to that of the commercial coated ferrofluid. In addition to the traditional characterization techniques, this study integrates advanced analytical methods, such as Atomic Force Microscopy (AFM), complementing traditional techniques such as Dynamic Light Scattering (DLS), to assess the nanoscale topography of both types of nanoparticles. Cytotoxicity studies on Calu-3 lung adenocarcinoma cells were conducted to evaluate the biocompatibility of the nanoparticles, demonstrating that NVs and FluidMAG exhibited minimal cytotoxic effects, particularly at lower concentrations. Cell internalization was confirmed for IONPs by magnetic cell separation whereas confocal microscopy analysis has been conducted for calcein-loaded NVs intracellular visualization. By integrating structural, chemical, and biological evaluations, we take an interdisciplinary approach which could also enable us to explore how variations in nanoparticle design (such as surface charge, size and coating) affect their performance in drug delivery and diagnostics. Moreover, combining physicochemical characterizations (e.g., hydrodynamic diameter, zeta potential and nanoparticles morphology) with biological evaluations (e.g., cellular uptake and safety profiles) allows for a holistic assessment of these nanocarriers to gain a comprehensive understanding of their behaviour and performance. This aspect is crucial for designing more efficient, safer, and targeted nanomedicines.

Inorganic nanoparticle-based nanogels and their biomedical applications

The advent of nanotechnology has brought tremendous progress in the field of biomedical science and opened avenues for advanced diagnostics and therapeutics applications. Several nanocarriers such as nanoparticles, liposomes, and nanogels have been designed to increase the drug efficiency and targeting ability in patients. Nanoparticles based on gold, silver, and iron are dominantly used for biomedical purposes owing to their biocompatibility properties. Nanoparticles offer an enhanced permeation into tissue vessels; however, their short half-life, toxicity, and off-site accumulations limit their functionality. The above shortcomings could be prevented by employing an integrated system combining nanoparticles with a nanogel-based system. These nanogels are 3D polymeric networks formed by physical and chemical crosslinking and are capable of incorporating nanoparticles, drugs, proteins, and genetic materials. Modification, functionalization, and introduction of inorganic nanoparticles have been shown to enhance the properties of nanogels, such as biocompatibility, stimuli responsiveness, stability, and selectivity. This review paper is focused on the design, synthesis, and biomedical application of inorganic nanoparticle-based nanogels. Current challenges and future perspectives will be briefly discussed to emphasize the versatile role of these multifunctional nanogels for therapeutic and diagnostic purposes.

Unraveling the Structure and Properties of High-Concentration Aqueous Iron Oxide Nanocolloids Free of Steric Stabilizers

Aqueous colloids with a high concentration of nanoparticles and free of steric stabilizers are prospective soft materials, the engineering of which is still challenging. Herein, we prepared superparamagnetic colloids with very large, up to 1350 g/L concentration of 11 nm nanoparticles via Fe2+ and Fe3+ coprecipitation, water washing, purification using cation-exchange resin, and stabilization with a monolayer of citrate anions (ζ potential of diluted dispersions about -35 mV). XRD, XPS, Mössbauer, and FTIR spectra elucidated the defective reverse spinel structure of magnetite/maghemite (Fe3O4/γ-Fe2O3) with a reduced content of Fe2+ cations. The viscosity increases with nanoparticle concentration and depends also on the nature of citrate salt, being one order of magnitude lower for lithium than sodium and potassium as counter-cation. SAXS/USAXS curves show power-law behavior in the scattering vector range between 0.1 and 0.002 nm-1, suggesting that particles interact forming fractal clusters, which are looser for Na+- and denser for Li+-citrate stabilizers (fractal dimensions of 1.9 and 2.4, respectively). In parallel, ATR-FTIR found increasing proportions of symmetric O-H stretching vibrations of ice-like interfacial water in the concentrated colloids. We hypothesize that the clusters arise due to the attraction of like-charge particles possibly involving the water shells and hydration of counter-cations; overlapping the clusters and transition to continuous non-Newtonian phases is seen at viscosity vs concentration plots at 700-900 g/L. The results shed new light on the structure of very concentrated nanocolloids and pave the way for their manufacturing and tailoring.

Magnetic-Plasmonic Core-Shell Nanoparticles: Properties, Synthesis and Applications for Cancer Detection and Treatment

Nanoparticles have been widely used in cancer diagnostics and treatment research due to their unique properties. Magnetic nanoparticles are popular in imaging techniques due to their ability to alter the magnetization field around them. Plasmonic nanoparticles are mainly applied in cancer treatments like photothermal therapy due to their ability to convert light into heat. While these nanoparticles are popular among their respective fields, magnetic-plasmonic core-shell nanoparticles (MPNPs) have gained popularity in recent years due to the combined magnetic and optical properties from the core and shell. MPNPs have stood out in cancer theranostics as a multimodal platform capable of serving as a contrast agent for imaging, a guidable drug carrier, and causing cellular ablation through photothermal energy conversion. In this review, we summarize the different properties of MPNPs and the most common synthesis approaches. We particularly discuss applications of MPNPs in cancer diagnosis and treatment based on different mechanisms using the magnetic and optical properties of the particles. Lastly, we look into current challenges they face for clinical applications and future perspectives using MPNPs for cancer detection and therapy.

Solvothermal synthesis of polyvinyl pyrrolidone encapsulated, amine-functionalized copper ferrite and its use as a magnetic resonance imaging contrast agent

Copper ferrite nanoparticles for use as MRI contrast agents were synthesized using two different methods. A novel microwave-assisted (MW) solvothermal method was developed and compared to a conventional 12-hour synthesis (Reflux) as an eco-friendlier approach. This innovative synthesis method successfully produced nanoparticles with enhanced properties compared to traditional ferrite materials. The nanoparticles' morphological and magnetic properties were evaluated and tested in in-vivo MRI studies. The results revealed both similarities and differences between the amine-functionalized copper ferrite nanoparticles. FTIR, XRD, HRTEM, and VSM analyses indicated improved properties in the CuFe2O4-NH2 MW particles, while AFM confirmed successful polymer encapsulation of the nanoparticles. For the CuFe2O4-NH2 MW sample, 76.8 wt% copper ferrite and 23.2 wt% magnetite were detected, with crystallite sizes of 8 ± 2 nm and 13 ± 2 nm, respectively. In the CuFe2O4-NH2 Refl. sample, in addition to these two magnetic phases, larger copper particles (31.6 wt%) were also formed. DLS analysis demonstrated that the CuFe2O4-NH2 MW sample exhibited excellent colloidal stability, maintaining its size distribution in aqueous media for 3 hours without aggregation, unlike the CuFe2O4-NH2 Refl. sample, which showed slight aggregation. The CuFe2O4-NH2 MW sample displayed superparamagnetic behavior (Ms: 15 emu/g, Mr: 0 emu/g, Hc: 0 Oe), while the CuFe2O4-NH2 Refl. sample exhibited ferromagnetic characteristics (Ms: 40 emu/g, Mr: 1.35 emu/g, Hc: 30 Oe). Both samples produced comparable results during in vitro MRI measurements, showing similar T2* relaxation and signal characteristics. Further in vivo studies demonstrated that both samples induced significant hypointense changes. The study provides valuable insights into the synthesis, properties, and potential applications of these materials, emphasizing the importance of eco-friendly methods and the optimization of ferrite-based MRI contrast agents.

A Review on Ultrasound-based Methods to Image the Distribution of Magnetic Nanoparticles in Biomedical Applications

Magnetic nanoparticles (MNPs) have gained significant attention in biomedical engineering and imaging applications due to their unique magnetic and mechanical properties. With their high magnetization and small size, MNPs serve as excitation sources for magnetically heating to destroy tumors (magnetic hyperthermia) and magnetically controlled drug carriers in magnetic drug targeting. However, effectively visualizing the distribution of MNPs during research or potential clinical use with low-cost modalities remains a critical challenge. Although magnetic resonance imaging provides pre- and post-procedural imaging, it is considered to be high cost, and real-time imaging during clinical procedures is limited. In contrast, ultrasound-based imaging methods offer the advantage of providing the potential for immediate feedback during clinical use and are considered to be a low-cost modality. Ultrasound-based imaging techniques, including magnetomotive ultrasound, magnetoacoustic tomography, and thermoacoustic imaging, emerged as promising approaches for imaging the distribution of MNPs. These techniques offer the potential for real-time imaging, facilitating precise therapy monitoring. By exploring the strengths and limitations of various ultrasound-based imaging techniques for MNPs, this review seeks to provide comprehensive insights that can guide researchers in selecting suitable ultrasound-based modalities and inspire further advancements in this exciting field.

Iron oxide nanoparticles coated with bioactive materials: a viable theragnostic strategy to improve osteosarcoma treatment

Osteosarcoma (OS) is distinguished as a high-grade malignant tumor, characterized by rapid systemic metastasis, particularly to the lungs, resulting in very low survival rates. Understanding the complexities of tumor development and mutation is the need of the hour for the advancement of targeted therapies in cancer care. A significant innovation in this area is the use of nanotechnology, specifically nanoparticles, to tackle various challenges in cancer treatment. Iron oxide nanoparticles stand out in both therapeutic and diagnostic applications, offering a versatile platform for targeted drug delivery, hyperthermia, magneto-thermal therapy, and combinational therapy using modulation of ferroptosis pathways. These nanoparticles are easy to synthesize, non-toxic, biocompatible, and display enhanced circulation time within the system. They can also be easily conjugated to anti-cancer drugs, targeting agents, or genetic vectors that respond to specific stimuli or pH changes. The surface functionalization of these nanoparticles using bioactive molecules unveils a promising and effective nanoparticle system for assisting osteosarcoma therapy. This review will summarize the current conventional therapies for osteosarcoma and their disadvantages, the synthesis and modification of iron oxide nanoparticles documented in the literature, cellular targeting and uptake mechanism, with focus on their functionalization using natural biomaterials and application strategies towards management of osteosarcoma. The review also compiles the translational challenges and future prospects that must be addressed for clinical advancements of iron oxide based osteosarcoma treatment in the future.

Metabolically-Driven Active Targeting of Magnetic Nanoparticles Functionalized with Glucuronic Acid to Glioblastoma: Application to MRI-Tracked Magnetic Hyperthermia Therapy

Glioblastoma continues to pose a major global health challenge due to its incurable nature. The need for new strategies to combat this devastating tumor is therefore paramount. Nanotechnology offers unique opportunities to develop innovative and more effective therapeutic approaches. However, most nanosystems developed to treat glioblastomas, especially those based on metallic nanoparticles (NPs), have proven unsuccessful due to their inability to efficiently target these tumors, which are particularly inaccessible due to the restrictions imposed by the blood-brain tumor barrier (BBTB). Here, an innovative strategy is presented to efficiently target metallic NPs to glioblastomas through glucose transporters (GLUT) overexpressed on the endothelial cells of glioblastoma microvasculature, particularly GLUT1. Specifically, Iron Oxide Nanoparticles (IONPs) are functionalized with glucuronic acid to promote GLUT-mediated transcytosis which is drastically boosted by inducing mild hypoglycemia. This metabolically-driven active targeting strategy has yielded unprecedented efficacy in targeting metallic NPs to glioblastomas. Moreover, these IONPs, designed to act as magnetic hyperthermia (MH) mediators, are used to conduct a proof-of-concept preclinical study on MRI-tracked MH therapy following intravenous administration, resulting in significant tumor growth delay. These findings demonstrate unparalleled efficiency in glioblastoma targeting and lay the ground for developing alternative therapeutic strategies to combat glioblastoma.

Nanostructures in Orthopedics: Advancing Diagnostics, Targeted Therapies, and Tissue Regeneration

Nanotechnology, delving into the realm of nanometric structures, stands as a transformative force in orthopedics, reshaping diagnostics, and numerous regenerative interventions. Commencing with diagnostics, this scientific discipline empowers accurate analyses of various diseases and implant stability, heralding an era of unparalleled precision. Acting as carriers for medications, nanomaterials introduce novel therapeutic possibilities, propelling the field towards more targeted and effective treatments. In arthroplasty, nanostructural modifications to implant surfaces not only enhance mechanical properties but also promote superior osteointegration and durability. Simultaneously, nanotechnology propels tissue regeneration, with nanostructured dressings emerging as pivotal elements in accelerating wound healing. As we navigate the frontiers of nanotechnology, ongoing research illuminates promising avenues for further advancements, assuring a future where orthopedic practices are not only personalized but also highly efficient, promising a captivating journey through groundbreaking innovations and tailored patient care.

Amphoteric β-cyclodextrin coated iron oxide magnetic nanoparticles: new insights into synthesis and application in MRI

This work presents a group of high-quality hydrophilic and negatively charged coated, iron oxide magnetic nanoparticles (MNPs) that have been prepared using a microwave-ultrasound-assisted protocol, and demonstrates the great impact that the synthetic strategy has on the resulting MNPs. The different coatings tested, including citric acid, carboxymethyl dextran and β-cyclodextrin (βCD)/citric acid have been compared and have shown good dispersibility and stability. The ability of βCD to maintain the inclusive properties of the coated MNPs has been proven as well as their cytocompatibility. An amino citrate-modified βCD is proposed and its capabilities as a flexible amphoteric adsorbing device have been studied. The NMR relaxometric properties of the coated MNPs have been investigated using field-cycling nuclear magnetic relaxation dispersion profiles. For the amino citrate-modified βCD system, the order of magnitude of the Néel relaxation time is in the typical range for superparamagnetic systems' reversal times, i.e., 10-10-10-7 s. The r d value corresponds to the physical radius of the magnetic core, suggesting that, in this particular case, the coating does not prevent the diffusive motion of water molecules, which provide the basis for potential future magnetic resonance imaging (MRI) applications.

Biomass-Derived Organonanomaterials as Contrast Agents for Efficient Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is a popular imaging tool that is valuable for the early detection and monitoring of malignancies because it does not involve radiation and is noninvasive. Metal-based contrast agents (CAs) are commonly used in clinical settings despite concerns about the toxicity of free metals. Therefore, finding alternative nontoxic imaging probes is vital. In this work, we have synthesized and effectively utilized sustainable biomass lignin-based all-organic nanoconjugates linked with nitroxide radicals as MRI CAs. Lignin grafted with poly(4-glycidyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl) (LPGT) exhibits a longitudinal relaxivity of 0.54 mM-1 s-1. LPGT shows exceptional characteristics, including resistance to reduction and nontoxicity toward living organisms. LPGT displays enhanced MRI contrast in the BALB/c mouse model for a duration exceeding 4.35 h. Our primary goal is to design MRI agents that are exceptionally effective sustainable biomass-derived materials and do not require the use of metals. Nicely, LPGT offers adequate contrast enhancement at 5-fold lower (0.020 mmol/kg) than the standard dose (0.1 mmol/kg), easing worries about toxic metal buildup. Consequently, LPGT shows promise as a feasible CA for metal-free MRI.

SS-31 modification alleviates ferroptosis induced by superparamagnetic iron oxide nanoparticles in hypoxia/reoxygenation cardiomyocytes

Superparamagnetic iron oxide nanoparticles (SPION) are widely used in cardiovascular applications. However, their potential to induce ferroptosis in myocardial cells post-ischemia-reperfusion hinders clinical adoption. We investigated the mechanisms behind SPION-induced cytotoxicity in myocardial cells and explored whether co-loading SPION with SS-31 (a kind of mitochondrial-targeted antioxidant peptide) could counteract this toxicity. To create SPION@SS-31, SS-31 was physically adsorbed onto SPION. To study the dose- and time-dependent cytotoxic effects and assess the influence of SS-31 on reducing SPION-induced damage, hypoxia/reoxygenation(H/R) H9C2 cells were treated with either SPION or SPION@SS-31. We examined the relationship between SPION and ferroptosis by measuring mitochondrial ROS, mitochondrial membrane potential (MMP), lipid peroxidation products, ATP, GSH, GPX4, mitochondrial structure, nonheme iron content, cellular iron regulation, and typical ferroptosis markers. The findings showed that SPION induced concentration- and time-dependent toxicity, marked by a significant cell viability loss and an increase in LDH levels. In contrast, SPION@SS-31 produced results comparable to the H/R group, implying that SS-31 can notably reduce cell damage induced by SPION. SPION disrupted cellular iron homeostasis, with FtH and FtMt expression increased and reduced levels of FPN1 and ABCB8, which led to the overload of mitochondrial iron. This iron dysregulation damaged mitochondrial function and integrity, causing ATP depletion, MMP loss, and decreased GPX4 and GSH levels, accompanied by a burst of mitochondrial lipid peroxidation, ultimately resulting in ferroptosis in H/R cardiomyocytes. Notably, SS-31 significantly alleviated SPION-induced ferroptosis by decreasing mitochondrial MDA production and maintaining GSH and GPX4 levels, indicating its possibility to reverse SPION-induced cytotoxicity. The viability of H/R cells and cells treated with SPION and Fer-1 did not differ statistically, whereas cells exposed to SPION along with inhibitors like 3-MA, zVAD, or Nec-1 showed a substantial loss in viability, implying that ferroptosis is the primary mechanism behind SPION-induced myocardial toxicity. SPION triggers mitochondrial lipid peroxidation by causing overload of iron, leading to ferroptosis in H/R H9C2 cells. Mitochondria appear to be the primary target of SPION-induced toxic effects. SS-31 demonstrates potential in inhibiting this ferroptosis by acting as a mitochondria-targeted antioxidant, suggesting that the modification of mitochondria-targeted antioxidant peptides represents an innovative and practical approach to attenuate the myocardial toxicity associated with SPION.

Synthesis of dumbbell-like heteronanostructures encapsulated in ferritin protein: Towards multifunctional protein based opto-magnetic nanomaterials for biomedical theranostic

Dumbbell-like hetero nanostructures based on gold and iron oxides is a promising material for biomedical applications, useful as versatile theranostic agents due the synergistic effect of their optical and magnetic properties. However, achieving precise control on their morphology, size dispersion, colloidal stability, biocompatibility and cell targeting remains as a current challenge. In this study, we address this challenge by employing biomimetic routes, using ferritin protein nanocages as template for these nanoparticles' synthesis. We present the development of an opto-magnetic nanostructures using the ferritin protein, wherein gold and iron oxide nanostructures were produced within its cavity. Initially, we investigated the synthesis of gold nanostructures within the protein, generating clusters and plasmonic nanoparticles. Subsequently, we optimized the conditions for the superparamagnetic nanoparticles synthesis through controlled iron oxidation, thereby enhancing the magnetic properties of the resulting system. Finally, we produce magnetic nanoparticles in the protein with gold clusters, achieving the coexistence of both nanostructures within a single protein molecule, a novel material unprecedented to date. We observed that factors such as temperature, metal/protein ratios, pH, dialysis, and purification processes all have an impact on protein recovery, loading efficiency, morphology, and nanoparticle size. Our findings highlight the development of ferritin-based nanomaterials as versatile platforms for potential biomedical use as multifunctional theranostic agents.

Phenolic-enabled nanotechnology: a new strategy for central nervous system disease therapy

Polyphenolic compounds have received tremendous attention in biomedicine because of their good biocompatibility and unique physicochemical properties. In recent years, phenolic-enabled nanotechnology (PEN) has become a hotspot of research in the medical field, and many promising studies have been reported, especially in the application of central nervous system (CNS) diseases. Polyphenolic compounds have superior anti-inflammatory and antioxidant properties, and can easily cross the blood‒brain barrier, as well as protect the nervous system from metabolic damage and promote learning and cognitive functions. However, although great advances have been made in this field, a comprehensive review regarding PEN-based nanomaterials for CNS therapy is lacking. A systematic summary of the basic mechanisms and synthetic strategies of PEN-based nanomaterials is beneficial for meeting the demand for the further development of novel treatments for CNS diseases. This review systematically introduces the fundamental physicochemical properties of PEN-based nanomaterials and their applications in the treatment of CNS diseases. We first describe the different ways in which polyphenols interact with other substances to form high-quality products with controlled sizes, shapes, compositions, and surface chemistry and functions. The application of PEN-based nanomaterials in the treatment of CNS diseases is then described, which provides a reference for subsequent research on the treatment of CNS diseases.

Evaluation and imaging of biodistribution of magnetic nanoparticles in a model of hepatic cirrhosis via alternating current biosusceptometry

In recent years, magnetic nanoparticles (MNPs) have exhibited theragnostic characteristics which confer a wide range of applications in the biomedical field. Consequently, through Alternating Current Biosusceptometry (ACB), magnetic nanoparticles can be used as tracers, allowing the study of healthy and cirrhotic livers and providing the ability to differentiate them through the reconstruction of quantitative images. The ACB system consists of a developing biomagnetic technique that has the ability to magnetize and measure the magnetic susceptibility of a material such as MNPs, thereby offering quantitative information about biological systems with magnetic tracers.

Development of Resorbable Phosphate-Based Glass Microspheres as MRI Contrast Media Agents

In this research, resorbable phosphate-based glass (PBG) compositions were developed using varying modifier oxides including iron (Fe2O3), copper (CuO), and manganese (MnO2), and then processed via a rapid single-stage flame spheroidisation process to manufacture dense (i.e., solid) and highly porous microspheres. Solid (63-200 µm) and porous (100-200 µm) microspheres were produced and characterised via SEM, XRD, and EDX to investigate their surface topography, structural properties, and elemental distribution. Complementary NMR investigations revealed the formation of Q2, Q1, and Q0 phosphate species within the porous and solid microspheres, and degradation studies performed to evaluate mass loss, particle size, and pH changes over 28 days showed no significant differences among the microspheres (63-71 µm) investigated. The microspheres produced were then investigated using clinical (1.5 T) and preclinical (7 T) MRI systems to determine the R1 and R2 relaxation rates. Among the compositions investigated, manganese-based porous and solid microspheres revealed enhanced levels of R2 (9.7-10.5 s-1 for 1.5 T; 17.1-18.9 s-1 for 7 T) and R1 (3.4-3.9 s-1 for 1.5 T; 2.2-2.3 s-1 for 7 T) when compared to the copper and iron-based microsphere samples. This was suggested to be due to paramagnetic ions present in the Mn-based microspheres. It is also suggested that the porosity in the resorbable PBG porous microspheres could be further explored for loading with drugs or other biologics. This would further advance these materials as MRI theranostic agents and generate new opportunities for MRI contrast-enhancement oral-delivery applications.

Temporal and spatial resolution of magnetosome degradation at the subcellular level in a 3D lung carcinoma model

Magnetic nanoparticles offer many exciting possibilities in biomedicine, from cell imaging to cancer treatment. One of the currently researched nanoparticles are magnetosomes, magnetite nanoparticles of high chemical purity synthesized by magnetotactic bacteria. Despite their therapeutic potential, very little is known about their degradation in human cells, and even less so of their degradation within tumours. In an effort to explore the potential of magnetosomes for cancer treatment, we have explored their degradation process in a 3D human lung carcinoma model at the subcellular level and with nanometre scale resolution. We have used state of the art hard X-ray probes (nano-XANES and nano-XRF), which allow for identification of distinct iron phases in each region of the cell. Our results reveal the progression of magnetite oxidation to maghemite within magnetosomes, and the biosynthesis of magnetite and ferrihydrite by ferritin.

Nanomaterials: leading immunogenic cell death-based cancer therapies

The field of oncology has transformed in recent years, with treatments shifting from traditional surgical resection and radiation therapy to more diverse and customized approaches, one of which is immunotherapy. ICD (immunogenic cell death) belongs to a class of regulatory cell death modalities that reactivate the immune response by facilitating the interaction between apoptotic cells and immune cells and releasing specific signaling molecules, and DAMPs (damage-associated molecular patterns). The inducers of ICD can elevate the expression of specific proteins to optimize the TME (tumor microenvironment). The use of nanotechnology has shown its unique potential. Nanomaterials, due to their tunability, targeting, and biocompatibility, have become powerful tools for drug delivery, immunomodulators, etc., and have shown significant efficacy in clinical trials. In particular, these nanomaterials can effectively activate the ICD, trigger a potent anti-tumor immune response, and maintain long-term tumor suppression. Different types of nanomaterials, such as biological cell membrane-modified nanoparticles, self-assembled nanostructures, metallic nanoparticles, mesoporous materials, and hydrogels, play their respective roles in ICD induction due to their unique structures and mechanisms of action. Therefore, this review will explore the latest advances in the application of these common nanomaterials in tumor ICD induction and discuss how they can provide new strategies and tools for cancer therapy. By gaining a deeper understanding of the mechanism of action of these nanomaterials, researchers can develop more precise and effective therapeutic approaches to improve the prognosis and quality of life of cancer patients. Moreover, these strategies hold the promise to overcome resistance to conventional therapies, minimize side effects, and lead to more personalized treatment regimens, ultimately benefiting cancer treatment.

A Comprehensive Review of Nanoparticles: From Classification to Application and Toxicity

Nanoparticles are structures that possess unique properties with high surface area-to-volume ratio. Their small size, up to 100 nm, and potential for surface modifications have enabled their use in a wide range of applications. Various factors influence the properties and applications of NPs, including the synthesis method and physical attributes such as size and shape. Additionally, the materials used in the synthesis of NPs are primary determinants of their application. Based on the chosen material, NPs are generally classified into three categories: organic, inorganic, and carbon-based. These categories include a variety of materials, such as proteins, polymers, metal ions, lipids and derivatives, magnetic minerals, and so on. Each material possesses unique attributes that influence the activity and application of the NPs. Consequently, certain NPs are typically used in particular areas because they possess higher efficiency along with tenable toxicity. Therefore, the classification and the base material in the NP synthesis hold significant importance in both NP research and application. In this paper, we discuss these classifications, exemplify most of the major materials, and categorize them according to their preferred area of application. This review provides an overall review of the materials, including their application, and toxicity.

Impact of Particle Size on the Nonlinear Magnetic Response of Iron Oxide Nanoparticles during Frequency Mixing Magnetic Detection

Magnetic nanoparticles (MNPs), particularly iron oxide nanoparticles (IONPs), play a pivotal role in biomedical applications ranging from magnetic resonance imaging (MRI) enhancement and cancer hyperthermia treatments to biosensing. This study focuses on the synthesis, characterization, and application of IONPs with two different size distributions for frequency mixing magnetic detection (FMMD), a technique that leverages the nonlinear magnetization properties of MNPs for sensitive biosensing. IONPs are synthesized through thermal decomposition and subsequent growth steps. Our findings highlight the critical influence of IONP size on the FMMD signal, demonstrating that larger particles contribute dominantly to the FMMD signal. This research advances our understanding of IONP behavior, underscoring the importance of size in their application in advanced diagnostic tools.

Dynamic 3D in vitro lung models: applications of inorganic nanoparticles for model development and characterization

Being a vital organ exposed to the external environment, the lung is susceptible to a plethora of pathogens and pollutants. This is reflected in high incidences of chronic respiratory diseases, which remain a leading cause of mortality world-wide and pose a persistent global burden. It is thus of paramount importance to improve our understanding of these pathologies and provide better therapeutic options. This necessitates the development of representative and physiologically relevant in vitro models. Advances in bioengineering have enabled the development of sophisticated models that not only capture the three-dimensional architecture of the cellular environment but also incorporate the dynamics of local biophysical stimuli. However, such complex models also require novel approaches that provide reliable characterization. Within this review we explore how 3D bioprinting and nanoparticles can serve as multifaceted tools to develop such dynamic 4D printed in vitro lung models and facilitate their characterization in the context of pulmonary fibrosis and breast cancer lung metastasis.

Radiosensitizing effects of heparinized magnetic iron oxide nanoparticles in colon cancer

The combination of radiation treatment and chemotherapy is currently the standard for management of cancer patients. However, safe doses do not often provide effective therapy, then pre-treated patients are forced to repeat treatment with often already increased tumor resistance to drugs and irradiation. One of the solutions we suggest is to improve primary course of radiation treatment via enhancing radiosensitivity of tumors by magnetic-guided iron oxide nanoparticles (magnetite). We obtained spherical heparinized iron oxide nanoparticles (hIONPs, ∼20 nm), characterized it by TEM, Infrared spectroscopy and DLS. Then hIONPs cytotoxicity was assessed for colon cancer cells (XTT assay) and cellular uptake of nanoparticles was analyzed with X-ray fluorescence. Combination of ionizing radiation (IR) and hIONPs in vitro caused an increase of G2/M arrest of cell cycle, mitotic errors and decrease in survival (compared with samples exposed to IR and hIONPs separately). The promising results were shown for magnetic-guided hIONPs in CT26-grafted BALB/C mice: the combination of intravenously administrated hIONPs and IR showed 20,8% T/C ratio (related to non-treated mice), while single radiation had no shown significant decrease in tumor growth (72,4%). Non-guided by magnets hIONPs with IR showed 57,9% of T/C. This indicates that ultra-small size and biocompatible molecule are not the key to successful nano-drug design, in each case, delivery technologies need to be improved when transferred to in vivo model.

Tumor versus Tumor Cell Targeting in Metal-Based Nanoparticles for Cancer Theranostics

The application of metal-based nanoparticles (mNPs) in cancer therapy and diagnostics (theranostics) has been a hot research topic since the early days of nanotechnology, becoming even more relevant in recent years. However, the clinical translation of this technology has been notably poor, with one of the main reasons being a lack of understanding of the disease and conceptual errors in the design of mNPs. Strikingly, throughout the reported studies to date on in vivo experiments, the concepts of "tumor targeting" and "tumor cell targeting" are often intertwined, particularly in the context of active targeting. These misconceptions may lead to design flaws, resulting in failed theranostic strategies. In the context of mNPs, tumor targeting can be described as the process by which mNPs reach the tumor mass (as a tissue), while tumor cell targeting refers to the specific interaction of mNPs with tumor cells once they have reached the tumor tissue. In this review, we conduct a critical analysis of key challenges that must be addressed for the successful targeting of either tumor tissue or cancer cells within the tumor tissue. Additionally, we explore essential features necessary for the smart design of theranostic mNPs, where 'smart design' refers to the process involving advanced consideration of the physicochemical features of the mNPs, targeting motifs, and physiological barriers that must be overcome for successful tumor targeting and/or tumor cell targeting.

Smart Design of ZnFe and ZnFe@Fe Nanoparticles for MRI-Tracked Magnetic Hyperthermia Therapy: Challenging Classical Theories of Nanoparticles Growth and Nanomagnetism

Iron Oxide Nanoparticles (IONPs) hold the potential to exert significant influence on fighting cancer through their theranostics capabilities as contrast agents (CAs) for magnetic resonance imaging (MRI) and as mediators for magnetic hyperthermia (MH). In addition, these capabilities can be improved by doping IONPs with other elements. In this work, the synthesis and characterization of single-core and alloy ZnFe novel magnetic nanoparticles (MNPs), with improved magnetic properties and more efficient magnetic-to-heat conversion, are reported. Remarkably, the results challenge classical nucleation and growth theories, which cannot fully predict the final size/shape of these nanoparticles and, consequently, their magnetic properties, implying the need for further studies to better understand the nanomagnetism phenomenon. On the other hand, leveraging the enhanced properties of these new NPs, successful tumor therapy by MH is achieved following their intravenous administration and tumor accumulation via the enhanced permeability and retention (EPR) effect. Notably, these results are obtained using a single low dose of MNPs and a single exposure to clinically suitable alternating magnetic fields (AMF). Therefore, as far as the authors are aware, for the first time, the successful application of intravenously administered MNPs for MRI-tracked MH tumor therapy in passively targeted tumor xenografts using clinically suitable conditions is demonstrated.

Key Insights on the Classification and Theranostic Applications of Magnetic Resonance Imaging Contrast Agents

Magnetic resonance imaging (MRI) is a non-invasive molecular imaging tool being extensively employed in clinical and biomedical research for the detection of a broad spectrum of diseases. This technique offers remarkable spatial resolution, good tissue penetration and a high soft tissue contrast. Contrast agents (CAs) have been regularly used in MRI tests to enhance the resolution of MR images and to visualize the diseased sites in the body. In the past years, considerable efforts have been devoted towards developing new theranostic MRI agents that can be tailored to integrate the targeting and therapeutic functions in a single agent. In this review, we have underlined the role of the MRI CAs in the developing field of 'theranostics' and their recent applications in the combined imaging and therapy of different types of tumors. In addition, this review also outlines the different categories of MRI CAs and their comprehensive classification based on different criteria such as chemical composition, relaxation mechanism and biodistribution with clinically relevant examples.

Recent Progress in Peptide-Based Molecular Probes for Disease Bioimaging

Recent strides in molecular pathology have unveiled distinctive alterations at the molecular level throughout the onset and progression of diseases. Enhancing the in vivo visualization of these biomarkers is crucial for advancing disease classification, staging, and treatment strategies. Peptide-based molecular probes (PMPs) have emerged as versatile tools due to their exceptional ability to discern these molecular changes with unparalleled specificity and precision. In this Perspective, we first summarize the methodologies for crafting innovative functional peptides, emphasizing recent advancements in both peptide library technologies and computer-assisted peptide design approaches. Furthermore, we offer an overview of the latest advances in PMPs within the realm of biological imaging, showcasing their varied applications in diagnostic and therapeutic modalities. We also briefly address current challenges and potential future directions in this dynamic field.

Modulation of calcium signaling and metabolic pathways in endothelial cells with magnetic fields

Calcium signaling plays a crucial role in various physiological processes, including muscle contraction, cell division, and neurotransmitter release. Dysregulation of calcium levels and signaling has been linked to a range of pathological conditions such as neurodegenerative disorders, cardiovascular disease, and cancer. Here, we propose a theoretical model that predicts the modulation of calcium ion channel activity and calcium signaling in the endothelium through the application of either a time-varying or static gradient magnetic field (MF). This modulation is achieved by exerting magnetic forces or torques on either biogenic or non-biogenic magnetic nanoparticles that are bound to endothelial cell membranes. Since calcium signaling in endothelial cells induces neuromodulation and influences blood flow control, treatment with a magnetic field shows promise for regulating neurovascular coupling and treating vascular dysfunctions associated with aging and neurodegenerative disorders. Furthermore, magnetic treatment can enable control over the decoding of Ca signals, ultimately impacting protein synthesis. The ability to modulate calcium wave frequencies using MFs and the MF-controlled decoding of Ca signaling present promising avenues for treating diseases characterized by calcium dysregulation.

Imaging Molecular Targets and Metabolic Pathways in Breast Cancer for Improved Clinical Management: Current Practice and Future Perspectives

Breast cancer is the most frequently diagnosed cancer and leading cause of cancer-related deaths worldwide. Timely decision-making that enables implementation of the most appropriate therapy or therapies is essential for achieving the best clinical outcomes in breast cancer. While clinicopathologic characteristics and immunohistochemistry have traditionally been used in decision-making, these clinical and laboratory parameters may be difficult to ascertain or be equivocal due to tumor heterogeneity. Tumor heterogeneity is described as a phenomenon characterized by spatial or temporal phenotypic variations in tumor characteristics. Spatial variations occur within tumor lesions or between lesions at a single time point while temporal variations are seen as tumor lesions evolve with time. Due to limitations associated with immunohistochemistry (which requires invasive biopsies), whole-body molecular imaging tools such as standard-of-care [18F]FDG and [18F]FES PET/CT are indispensable in addressing this conundrum. Despite their proven utility, these standard-of-care imaging methods are often unable to image a myriad of other molecular pathways associated with breast cancer. This has stimulated interest in the development of novel radiopharmaceuticals targeting other molecular pathways and processes. In this review, we discuss validated and potential roles of these standard-of-care and novel molecular approaches. These approaches' relationships with patient clinicopathologic and immunohistochemical characteristics as well as their influence on patient management will be discussed in greater detail. This paper will also introduce and discuss the potential utility of novel PARP inhibitor-based radiopharmaceuticals as non-invasive biomarkers of PARP expression/upregulation.

Inorganic nanocarriers for siRNA delivery for cancer treatments

RNA interference is one of the emerging methodologies utilized in the treatment of a wide variety of diseases including cancer. This method specifically uses therapeutic RNAs (TpRNAs) like small interfering RNAs (siRNAs) to regulate/silence the cancer-linked genes, thereby minimizing the distinct activities of the cancer cells while aiding in their apoptosis. But, many complications arise during the transport/delivery of these TpRNAs that include poor systemic circulation, instability/degradation inside the body environment, no targeting capacity and also low cellular internalization. These difficulties can be overcome by using nanocarriers to deliver the TpRNAs inside the cancer cells. The following are the various categories of nanocarriers-viral vectors (e.g. lentivirus and adenovirus) and non-viral nanocarriers (self-assembling nanocarriers and inorganic nanocarriers). Viral vectors suffer from disadvantages like high immunogenicity compared to the non-viral nanocarriers. Among non-viral nanocarriers, inorganic nanocarriers gained significant attention as their inherent properties (like magnetic properties) can aid in the effective cellular delivery of the TpRNAs. Most of the prior reports have discussed about the delivery of TpRNAs through self-assembling nanocarriers; however very few have reviewed about their delivery using the inorganic nanoparticles. Therefore, in this review, we have mainly focussed on the delivery of TpRNAs-i.e. siRNA, especially programmed death ligand-1 (PD-L1), survivin, B-cell lymphoma-2 (Bcl-2), vascular endothelial growth factor and other siRNAs using the inorganic nanoparticles-mainly magnetic, metal and silica nanoparticles. Moreover, we have also discussed about the combined delivery of these TpRNAs along with chemotherapeutic drugs (mainly doxorubicin) andin vitroandin vivotherapeutic effectiveness.

Recent Advances in Nanobiotechnology for the Treatment of Non-Hodgkin's Lymphoma

Lymphoma is the eighth most common type of cancer worldwide. Currently, lymphoma is mainly classified into two main groups: Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL), with NHL accounting for 80% to 90% of the cases. NHL is primarily divided into B, T, and natural killer (NK) cell lymphoma. Nanotechnology is developing rapidly and has made significant contributions to the field of medicine. This review summarizes the advancements of nanobiotechnology in recent years and its applications in the treatment of NHL, especially in diffuse large B cell lymphoma (DLBCL), primary central nervous system lymphoma (PCNSL), and follicular lymphoma (FL). The technologies discussed include clinical imaging, targeted drug delivery, photodynamic therapy (PDT), and thermodynamic therapy (TDT) for lymphoma. This review aims to provide a better understanding of the use of nanotechnology in the treatment of non-Hodgkin's lymphoma.

Helios as a Potential Biomarker in Systemic Lupus Erythematosus and New Therapies Based on Immunosuppressive Cells

The Helios protein (encoded by the IKZF2 gene) is a member of the Ikaros transcription family and it has recently been proposed as a promising biomarker for systemic lupus erythematosus (SLE) disease progression in both mouse models and patients. Helios is beginning to be studied extensively for its influence on the T regulatory (Treg) compartment, both CD4+ Tregs and KIR+/Ly49+ CD8+ Tregs, with alterations to the number and function of these cells correlated to the autoimmune phenomenon. This review analyzes the most recent research on Helios expression in relation to the main immune cell populations and its role in SLE immune homeostasis, specifically focusing on the interaction between T cells and tolerogenic dendritic cells (tolDCs). This information could be potentially useful in the design of new therapies, with a particular focus on transfer therapies using immunosuppressive cells. Finally, we will discuss the possibility of using nanotechnology for magnetic targeting to overcome some of the obstacles related to these therapeutic approaches.

Single and Multitarget Systems for Drug Delivery and Detection: Up-to-Date Strategies for Brain Disorders

This review summarizes the recent findings on the development of different types of single and multitarget nanoparticles for disease detection and drug delivery to the brain, focusing on promising active principles encapsulated and nanoparticle surface modification and functionalization. Functionalized nanoparticles have emerged as promising tools for the diagnosis and treatment of brain disorders, offering a novel approach to addressing complex neurological challenges. They can act as drug delivery vehicles, transporting one or multiple therapeutic agents across the blood-brain barrier and precisely releasing them at the site of action. In diagnostics, functionalized nanoparticles can serve as highly sensitive contrast agents for imaging techniques such as magnetic resonance imaging and computed tomography scans. By attaching targeting ligands to the nanoparticles, they can selectively accumulate in the affected areas of the brain, enhancing the accuracy of disease detection. This enables early diagnosis and monitoring of conditions like Alzheimer's or Parkinson's diseases. While the field is still evolving, functionalized nanoparticles represent a promising path for advancing our ability to diagnose and treat brain disorders with greater precision, reduced invasiveness, and improved therapeutic outcomes.

A Novel Magnetic Responsive miR-26a@SPIONs-OECs for Spinal Cord Injury: Triggering Neural Regeneration Program and Orienting Axon Guidance in Inhibitory Astrocytic Environment

Addressing the challenge of promoting directional axonal regeneration in a hostile astrocytic scar, which often impedes recovery following spinal cord injury (SCI), remains a daunting task. Cell transplantation is a promising strategy to facilitate nerve restoration in SCI. In this research, a pro-regeneration system is developed, namely miR-26a@SPIONs-OECs, for olfactory ensheathing cells (OECs), a preferred choice for promoting nerve regeneration in SCI patients. These entities show high responsiveness to external magnetic fields (MF), leading to synergistic multimodal cues to enhance nerve regeneration. First, an MF stimulates miR-26a@SPIONs-OECs to release extracellular vesicles (EVs) rich in miR-26a. This encourages axon growth by inhibiting PTEN and GSK-3β signaling pathways in neurons. Second, miR-26a@SPIONs-OECs exhibit a tendency to migrate and orientate along the direction of the MF, thereby potentially facilitating neuronal reconnection through directional neurite elongation. Third, miR-26a-enriched EVs from miR-26a@SPIONs-OECs can interact with host astrocytes, thereby diminishing inhibitory cues for neurite growth. In a rat model of SCI, the miR-26a@SPIONs-OECs system led to significantly improved morphological and motor function recovery. In summary, the miR-26a@SPIONS-OECs pro-regeneration system offers innovative insights into engineering exogenous cells with multiple additional cues, augmenting their efficacy for stimulating and guiding nerve regeneration within a hostile astrocytic scar in SCI.

Emergence of magnetic nanoparticles in photothermal and ferroptotic therapies

With their distinctive physicochemical features, nanoparticles have gained recognition as effective multifunctional tools for biomedical applications, with designs and compositions tailored for specific uses. Notably, magnetic nanoparticles stand out as first-in-class examples of multiple modalities provided by the iron-based composition. They have long been exploited as contrast agents for magnetic resonance imaging (MRI) or as anti-cancer agents generating therapeutic hyperthermia through high-frequency magnetic field application, known as magnetic hyperthermia (MHT). This review focuses on two more recent applications in oncology using iron-based nanomaterials: photothermal therapy (PTT) and ferroptosis. In PTT, the iron oxide core responds to a near-infrared (NIR) excitation and generates heat in its surrounding area, rivaling the efficiency of plasmonic gold-standard nanoparticles. This opens up the possibility of a dual MHT + PTT approach using a single nanomaterial. Moreover, the iron composition of magnetic nanoparticles can be harnessed as a chemotherapeutic asset. Degradation in the intracellular environment triggers the release of iron ions, which can stimulate the production of reactive oxygen species (ROS) and induce cancer cell death through ferroptosis. Consequently, this review emphasizes these emerging physical and chemical approaches for anti-cancer therapy facilitated by magnetic nanoparticles, combining all-in-one functionalities.

Tumor-targeting cell membrane-coated nanorings for magnetic-hyperthermia-induced tumor ablation

Magnetic hyperthermia has attracted considerable attention for efficient cancer therapy because of its noninvasive nature, deep tissue penetration, and minimal damage to healthy tissues. Herein, we have fused cancer cell membrane fragments with lipids and cloaked them on magnetic nanorings to form targeted Fe nanorings (TF) for tumor-targeted magnetic hyperthermia-induced tumor ablation. In our approach, cell membrane fragments from cancer cells were fused with lipids to form vesicles, which could efficiently encapsulate magnetic nanorings, thereby forming TF. We observed that TF have high tumor uptake via homotypic targeting, where cancer cells take up TF through membrane fusion. Under an external alternating magnetic field (AMF), TF accumulated in the tumors are heated, driving magnetic-hyperthermia-induced tumor cell death. Our in vitro studies show that self-targeting TF efficiently localized in cancer cells and induced cell death with an AMF, which was shown by a live/dead assay. Our findings demonstrate the potential of TF in tumor ablation, thereby making them promising and efficient nanosystems for tumor-targeted theranostics.

Effect of Highly Hydrophilic Superparamagnetic Iron Oxide Nanoparticles on Macrophage Function and Survival

Superparamagnetic iron oxide nanoparticles (SPIONs) have garnered significant attention in the medical sector due to their exceptional superparamagnetic properties and reliable tracking capabilities. In this study, we investigated the immunotoxicity of SPIONs with a modified surface to enhance hydrophilicity and prevent aggregate formation. The synthesized SPIONs exhibited a remarkably small size (~4 nm) and underwent surface modification using a novel "haircut" reaction strategy. Experiments were conducted in vitro using a human monocytic cell line (THP-1). SPIONs induced dose-dependent toxicity to THP-1 cells, potentially by generating ROS and initiating the apoptotic pathway in the cells. Concentrations up to 10 μg/mL did not affect the expression of Nrf2, HO-1, NF-κB, or TLR-4 proteins. The results of the present study demonstrated that highly hydrophilic SPIONs were highly toxic to immune cells; however, they did not activate pathways of inflammation and immune response. Further investigation into the mechanisms of cytotoxicity is warranted to develop a synthetic approach for producing effective, highly hydrophilic SPIONs with little to no side effects.

Iron Oxide Nanoparticles in Cancer Treatment: Cell Responses and the Potency to Improve Radiosensitivity

The main concept of radiosensitization is making the tumor tissue more responsive to ionizing radiation, which leads to an increase in the potency of radiation therapy and allows for decreasing radiation dose and the concomitant side effects. Radiosensitization by metal oxide nanoparticles is widely discussed, but the range of mechanisms studied is not sufficiently codified and often does not reflect the ability of nanocarriers to have a specific impact on cells. This review is focused on the magnetic iron oxide nanoparticles while they occupied a special niche among the prospective radiosensitizers due to unique physicochemical characteristics and reactivity. We collected data about the possible molecular mechanisms underlying the radiosensitizing effects of iron oxide nanoparticles (IONPs) and the main approaches to increase their therapeutic efficacy by variable modifications.

Nanomaterials: a promising multimodal theranostics platform for thyroid cancer

Thyroid cancer is the most prevalent malignant neoplasm of the cervical region and endocrine system, characterized by a discernible upward trend in incidence over recent years. Ultrasound-guided fine needle aspiration is the current standard for preoperative diagnosis of thyroid cancer, albeit with limitations and a certain degree of false-negative outcomes. Although differentiated thyroid carcinoma generally exhibits a favorable prognosis, dedifferentiation is associated with an unfavorable clinical course. Anaplastic thyroid cancer, characterized by high malignancy and aggressiveness, remains an unmet clinical need with no effective treatments available. The emergence of nanomedicine has opened new avenues for cancer theranostics. The unique features of nanomaterials, including multifunctionality, modifiability, and various detection modes, enable non-invasive and convenient thyroid cancer diagnosis through multimodal imaging. For thyroid cancer treatment, nanomaterial-based photothermal therapy or photodynamic therapy, combined with chemotherapy, radiotherapy, or gene therapy, holds promise in reducing invasiveness and prolonging patient survival or alleviating pain in individuals with anaplastic thyroid carcinoma. Furthermore, nanomaterials enable simultaneous diagnosis and treatment of thyroid cancer. This review aims to provide a comprehensive survey of the latest developments in nanomaterials for thyroid cancer diagnosis and treatment and encourage further research in developing innovative and effective theranostic approaches for thyroid cancer.

3,4-Dihydroxiphenylacetic Acid-Based Universal Coating Technique for Magnetic Nanoparticles Stabilization for Biomedical Applications

Magnetic nanoparticles based on iron oxide attract researchers' attention due to a wide range of possible applications in biomedicine. As synthesized, most of the magnetic nanoparticles do not form the stable colloidal solutions that are required for the evaluation of their interactions with cells or their efficacy on animal models. For further application in biomedicine, magnetic nanoparticles must be further modified with biocompatible coating. Both the size and shape of magnetic nanoparticles and the chemical composition of the coating have an effect on magnetic nanoparticles' interactions with living objects. Thus, a universal method for magnetic nanoparticles' stabilization in water solutions is needed, regardless of how magnetic nanoparticles were initially synthesized. In this paper, we propose the versatile and highly reproducible ligand exchange technique of coating with 3,4-dihydroxiphenylacetic acid (DOPAC), based on the formation of Fe-O bonds with hydroxyl groups of DOPAC leading to the hydrophilization of the magnetic nanoparticles' surfaces following phase transfer from organic solutions to water. The proposed technique allows for obtaining stable water-colloidal solutions of magnetic nanoparticles with sizes from 21 to 307 nm synthesized by thermal decomposition or coprecipitation techniques. Those stabilized by DOPAC nanoparticles were shown to be efficient in the magnetomechanical actuation of DNA duplexes, drug delivery of doxorubicin to cancer cells, and targeted delivery by conjugation with antibodies. Moreover, the diversity of possible biomedical applications of the resulting nanoparticles was presented. This finding is important in terms of nanoparticle design for various biomedical applications and will reduce nanomedicines manufacturing time, along with difficulties related to comparative studies of magnetic nanoparticles with different magnetic core characteristics.

Large-scale in situ self-assembly and doping engineering of zinc ferrite nanoclusters for high performance bioimaging

Iron oxide nanomaterials has good biocompatibility and safety, and has been used as contrast agents for magnetic resonance imaging (MRI). However, its clinical usefulness is hampered by its difficult preparation on large scale, its rapid clearance in vivo and low target tissue enrichment efficiency. Here, we report the synthesis of water-soluble, biocompatible, superparamagnetic non-stoichiometric zinc ferrite nanoclusters (nZFNCs) of approximately 50 g in a single batch using a one-pot synthesis technique. nZFNCs is a secondary cluster structure with a size of about 40 nm composed of zinc-doped iron oxide nanoparticles with a size of about 6 nm. The surface of nZFNCS is endowed with a large number of carboxyl groups as active sites. By simply controlling the synthesis process and adjusting the proportion of metal precursors, the amount of zinc doping can be controlled, while maintaining the same size to ensure similar pharmacokinetics. Compared with undoped, the magnetic responsiveness and relaxation efficiency of nZFNCs are significantly improved, and the transverse relaxation efficiency (r2) can reach 425.5 mM-1 s-1 (doping amount x = 0.25), which is 7 times higher than that of commercial Resovist and 10 times higher than that of Feridex. In vivo imaging results also further confirmed the excellent contrast enhancement performance of the nanoclusters, which can achieve high contrast for more than 2 h in the liver. The advantage of this platform over comparable systems is that the contrast enhancement features are derived from simple techniques that do not require complex physical and chemical methods.

Laser-Ablative Synthesis of Silicon-Iron Composite Nanoparticles for Theranostic Applications

The combination of photothermal and magnetic functionalities in one biocompatible nanoformulation forms an attractive basis for developing multifunctional agents for biomedical theranostics. Here, we report the fabrication of silicon-iron (Si-Fe) composite nanoparticles (NPs) for theranostic applications by using a method of femtosecond laser ablation in acetone from a mixed target combining silicon and iron. The NPs were then transferred to water for subsequent biological use. From structural analyses, it was shown that the formed Si-Fe NPs have a spherical shape and sizes ranging from 5 to 150 nm, with the presence of two characteristic maxima around 20 nm and 90 nm in the size distribution. They are mostly composed of silicon with the presence of a significant iron silicide content and iron oxide inclusions. Our studies also show that the NPs exhibit magnetic properties due to the presence of iron ions in their composition, which makes the formation of contrast in magnetic resonance imaging (MRI) possible, as it is verified by magnetic resonance relaxometry at the proton resonance frequency. In addition, the Si-Fe NPs are characterized by strong optical absorption in the window of relative transparency of bio-tissue (650-950 nm). Benefiting from such absorption, the Si-Fe NPs provide strong photoheating in their aqueous suspensions under continuous wave laser excitation at 808 nm. The NP-induced photoheating is described by a photothermal conversion efficiency of 33-42%, which is approximately 3.0-3.3 times larger than that for pure laser-synthesized Si NPs, and it is explained by the presence of iron silicide in the NP composition. Combining the strong photothermal effect and MRI functionality, the synthesized Si-Fe NPs promise a major advancement of modalities for cancer theranostics, including MRI-guided photothermal therapy and surgery.

Endogenous and Exogenous Antioxidants as Agents Preventing the Negative Effects of Contrast Media (Contrast-Induced Nephropathy)

The use of conventional contrast media for diagnostic purposes (in particular, Gd-containing and iodinated agents) causes a large number of complications, the most common of which is contrast-induced nephropathy. It has been shown that after exposure to contrast agents, oxidative stress often occurs in patients, especially in people suffering from various diseases. Antioxidants in the human body can diminish the pathological consequences of the use of contrast media by suppressing oxidative stress. This review considers the research studies on the role of antioxidants in preventing the negative consequences of the use of contrast agents in diagnostics (mainly contrast-induced nephropathy) and the clinical trials of different antioxidant drugs against contrast-induced nephropathy. Composite antioxidant/contrast systems as theranostic agents are also considered.

Application of Nanoparticles in the Diagnosis of Gastrointestinal Diseases: A Complete Future Perspective

The diagnosis of gastrointestinal (GI) diseases currently relies primarily on invasive procedures like digestive endoscopy. However, these procedures can cause discomfort, respiratory issues, and bacterial infections in patients, both during and after the examination. In recent years, nanomedicine has emerged as a promising field, providing significant advancements in diagnostic techniques. Nanoprobes, in particular, offer distinct advantages, such as high specificity and sensitivity in detecting GI diseases. Integration of nanoprobes with advanced imaging techniques, such as nuclear magnetic resonance, optical fluorescence imaging, tomography, and optical correlation tomography, has significantly enhanced the detection capabilities for GI tumors and inflammatory bowel disease (IBD). This synergy enables early diagnosis and precise staging of GI disorders. Among the nanoparticles investigated for clinical applications, superparamagnetic iron oxide, quantum dots, single carbon nanotubes, and nanocages have emerged as extensively studied and utilized agents. This review aimed to provide insights into the potential applications of nanoparticles in modern imaging techniques, with a specific focus on their role in facilitating early and specific diagnosis of a range of GI disorders, including IBD and colorectal cancer (CRC). Additionally, we discussed the challenges associated with the implementation of nanotechnology-based GI diagnostics and explored future prospects for translation in this promising field.

Hydrophilic Copolymers with Hydroxamic Acid Groups as a Protective Biocompatible Coating of Maghemite Nanoparticles: Synthesis, Physico-Chemical Characterization and MRI Biodistribution Study

Superparamagnetic iron oxide nanoparticles (SPION) with a "non-fouling" surface represent a versatile group of biocompatible nanomaterials valuable for medical diagnostics, including oncology. In our study we present a synthesis of novel maghemite (γ-Fe₂O₃) nanoparticles with positive and negative overall surface charge and their coating by copolymer P(HPMA-co-HAO) prepared by RAFT (reversible addition-fragmentation chain-transfer) copolymerization of N-(2-hydroxypropyl)methacrylamide (HPMA) with N-[2-(hydroxyamino)-2-oxo-ethyl]-2-methyl-prop-2-enamide (HAO). Coating was realized via hydroxamic acid groups of the HAO comonomer units with a strong affinity to maghemite. Dynamic light scattering (DLS) demonstrated high colloidal stability of the coated particles in a wide pH range, high ionic strength, and the presence of phosphate buffer (PBS) and serum albumin (BSE). Transmission electron microscopy (TEM) images show a narrow size distribution and spheroid shape. Alternative coatings were prepared by copolymerization of HPMA with methyl 2-(2-methylprop-2-enoylamino)acetate (MMA) and further post-polymerization modification with hydroxamic acid groups, carboxylic acid and primary-amino functionalities. Nevertheless, their colloidal stability was worse in comparison with P(HPMA-co-HAO). Additionally, P(HPMA-co-HAO)-coated nanoparticles were subjected to a bio-distribution study in mice. They were cleared from the blood stream by the liver relatively slowly, and their half-life in the liver depended on their charge; nevertheless, both cationic and anionic particles revealed a much shorter metabolic clearance rate than that of commercially available ferucarbotran.

N-Acetylcysteine-Loaded Magnetic Nanoparticles for Magnetic Resonance Imaging

Acute respiratory distress syndrome (ARDS) is a life-threatening condition characterized by the rapid onset of lung inflammation Therefore, monitoring the spatial distribution of the drug directly administered to heterogeneously damaged lungs is desirable. In this work, we focus on optimizing the drug N-acetylcysteine (NAC) adsorption on poly-l-lysine-modified magnetic nanoparticles (PLLMNPs) to monitor the drug spatial distribution in the lungs using magnetic resonance imaging (MRI) techniques. The physicochemical characterizations of the samples were conducted in terms of morphology, particle size distributions, surface charge, and magnetic properties followed by the thermogravimetric quantification of NAC coating and cytotoxicity experiments. The sample with the theoretical NAC loading concentration of 0.25 mg/mL was selected as an optimum due to the hydrodynamic nanoparticle size of 154 nm, the surface charge of +32 mV, good stability, and no cytotoxicity. Finally, MRI relaxometry confirmed the suitability of the sample to study the spatial distribution of the drug in vivo using MRI protocols. We showed the prevailing transverse relaxation with high transverse relaxivity values and a high r₂⁽*⁾/r₁ ratio, causing visible hypointensity in the final MRI signal. Furthermore, NAC adsorption significantly affects the relaxation properties of PLLMNPs, which can help monitor drug release in vitro/in vivo.

High Biocompatibility, MRI Enhancement, and Dual Chemo- and Thermal-Therapy of Curcumin-Encapsulated Alginate/Fe3O4 Nanoparticles

(1) Background: Magnetite (Fe₃O₄) nanoparticles have great potential for biomedical applications, including hyperthermia and magnetic resonance imaging. In this study, we aimed to identify the biological activity of nanoconjugates composed of superparamagnetic Fe₃O₄ nanoparticles coated with alginate and curcumin (Fe₃O₄/Cur@ALG) in cancer cells. (2) Methods: The nanoparticles were evaluated for the biocompatibility and toxicity on mice. The MRI enhancement and hyperthermia capacities of Fe₃O₄/Cur@ALG were determined in both in vitro and in vivo sarcoma models. (3) Results: The results show that the magnetite nanoparticles exhibit high biocompatibility and low toxicity in mice at Fe₃O₄ concentrations up to 120 mg/kg when administered via intravenous injection. The Fe₃O₄/Cur@ALG nanoparticles enhance the magnetic resonance imaging contrast in cell cultures and tumor-bearing Swiss mice. The autofluorescence of curcumin also allowed us to observe the penetration of the nanoparticles into sarcoma 180 cells. In particular, the nanoconjugates synergistically inhibit the growth of sarcoma 180 tumors via magnetic heating and the anticancer effects of curcumin, both in vitro and in vivo. (4) Conclusions: Our study reveals that Fe₃O₄/Cur@ALG has a high potential for medicinal applications and should be further developed for cancer diagnosis and treatment.

Iron oxide nanoparticles carried by probiotics for iron absorption: a systematic review

BACKGROUND

One-third of the world's population has anemia, contributing to higher morbidity and death and impaired neurological development. Conventional anemia treatment raises concerns about iron bioavailability and gastrointestinal (GI) adverse effects. This research aims to establish how iron oxide nanoparticles (IONPs) interact with probiotic cells and how they affect iron absorption, bioavailability, and microbiota variation.

METHODS

Pointing to the study of the literature and developing a review and critical synthesis, a robust search methodology was utilized by the authors. The literature search was performed in the PubMed, Scopus, and Web of Science databases. Information was collected between January 2017 and June 2022 using the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) protocols for systematic reviews and meta-analyses. We identified 122 compatible research articles.

RESULTS

The research profile of the selected scientific articles revealed the efficacy of IONPs treatment carried by probiotics versus conventional treatment. Therefore, the authors employed content assessment on four topics to synthesize previous studies. The key subjects of the reviewed reports are the characteristics of the IONPs synthesis method, the evaluation of cell absorption and cytotoxicity of IONPs, and the transport of IONPs with probiotics in treating anemia.

CONCLUSIONS

To ensure a sufficient iron level in the enterocyte, probiotics with the capacity to attach to the gut wall transport IONPs into the enterocyte, where the maghemite nanoparticles are released.

Metal and Metal Oxides Nanoparticles and Nanosystems in Anticancer and Antiviral Theragnostic Agents

The development of antiviral treatment and anticancer theragnostic agents in recent decades has been associated with nanotechnologies, and primarily with inorganic nanoparticles (INPs) of metal and metal oxides. The large specific surface area and its high activity make it easy to functionalize INPs with various coatings (to increase their stability and reduce toxicity), specific agents (allowing retention of INPs in the affected organ or tissue), and drug molecules (for antitumor and antiviral therapy). The ability of magnetic nanoparticles (MNPs) of iron oxides and ferrites to enhance proton relaxation in specific tissues and serve as magnetic resonance imaging contrast agents is one of the most promising applications of nanomedicine. Activation of MNPs during hyperthermia by an external alternating magnetic field is a promising method for targeted cancer therapy. As therapeutic tools, INPs are promising carriers for targeted delivery of pharmaceuticals (either anticancer or antiviral) via magnetic drug targeting (in case of MNPs), passive or active (by attaching high affinity ligands) targeting. The plasmonic properties of Au nanoparticles (NPs) and their application for plasmonic photothermal and photodynamic therapies have been extensively explored recently in tumor treatment. The Ag NPs alone and in combination with antiviral medicines reveal new possibilities in antiviral therapy. The prospects and possibilities of INPs in relation to magnetic hyperthermia, plasmonic photothermal and photodynamic therapies, magnetic resonance imaging, targeted delivery in the framework of antitumor theragnostic and antiviral therapy are presented in this review.