New advances strategies for surface functionalization of iron oxide magnetic nano particles (IONPs)

Advancements in enzyme immobilization on magnetic nanomaterials: toward sustainable industrial applications

Enzymes are widely used in biofuels, food, and pharmaceuticals. The immobilization of enzymes on solid supports, particularly magnetic nanomaterials, enhances their stability and catalytic activity. Magnetic nanomaterials are chosen for their versatility, large surface area, and superparamagnetic properties, which allow for easy separation and reuse in industrial processes. Researchers focus on the synthesis of appropriate nanomaterials tailored for specific purposes. Immobilization protocols are predefined and adapted to both enzymes and support requirements for optimal efficiency. This review provides a detailed exploration of the application of magnetic nanomaterials in enzyme immobilization protocols. It covers methods, challenges, advantages, and future perspectives, starting with general aspects of magnetic nanomaterials, their synthesis, and applications as matrices for solid enzyme stabilization. The discussion then delves into existing enzymatic immobilization methods on magnetic nanomaterials, highlighting advantages, challenges, and potential applications. Further sections explore the industrial use of various enzymes immobilized on these materials, the development of enzyme-based bioreactors, and prospects for these biocatalysts. In summary, this review provides a concise comparison of the use of magnetic nanomaterials for enzyme stabilization, highlighting potential industrial applications and contributing to manufacturing optimization.

Redefining Chalcone Synthesis: Aldol Adduct Elimination for the Rapid Access to Thienyl Chalcones

This paper introduces a unique and novel method for synthesizing thienyl chalcones using iron oxide nanoparticles (FeONPs) as a heterogeneous catalyst. It stands out as a rare example in the literature for the synthesis of these chalcones from 1,3-diketones and various aromatic aldehydes. The magnetic FeONPs employed as the catalyst bring several advantages, including their efficiency, affordability, and ecofriendly nature, making them an attractive choice for producing thiophene chalcones. One noteworthy aspect of this methodology is the utilization of mild reaction conditions, which greatly simplify the operational aspects of the reaction. Synthesized chalcones were confirmed through the application of various techniques, proton-NMR, 13C NMR, mass spectrometry, and single-crystal X-ray diffraction analysis. These analyses provide valuable insights into the chemical compositions and structural characteristics of the synthesized compounds. Significantly, this methodology is reported for the first time in the literature, indicating its novelty and contribution to the field of chalcone synthesis.

The Story of Ferumoxytol: Synthesis Production, Current Clinical Applications, and Therapeutic Potential

Ferumoxytol, approved by the U.S. Food and Drug Administration in 2009, is one of the intravenous iron oxide nanoparticles authorized for the treatment of iron deficiency in chronic kidney disease and end-stage renal disease. With its exceptional magnetic properties, catalytic activity, and immune activity, as well as good biocompatibility and safety, ferumoxytol has gained significant recognition in various biomedical diagnoses and treatments. Unlike most existing reviews on this topic, this review primarily focuses on the recent clinical and preclinical advances of ferumoxytol in disease treatment, spanning anemia, cancer, infectious inflammatory diseases, regenerative medicine application, magnetic stimulation for neural modulation, etc. Additionally, the newly discovered mechanisms associated with the biological effects of ferumoxytol are discussed, including its magnetic, catalytic, and immunomodulatory properties. Finally, the summary and future prospects concerning the treatment and application of ferumoxytol-based nanotherapeutics are presented.

Methotrexate-conjugated zinc oxide nanoparticles exert a substantially improved cytotoxic effect on lung cancer cells by inducing apoptosis

In the current study, we report the synthesis of methotrexate-conjugated zinc oxide nanoparticles (MTX-ZnONPs) and their high efficacy against lung cancer cells. Conjugation of MTX with ZnONPs was authenticated by UV-vis spectroscopy, dynamic light scattering (DLS), Fourier-transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). This drug-nanoconjugate also showed high drug-loading efficiency. The therapeutic efficacy of MTX-ZnONPs was further tested in vitro against A549 cells, and the results of MTT and LDH release assays showed that MTX-ZnONPs, in addition to free MTX, were efficient in exerting cytotoxic effect on A549 cells; however, the effectiveness of MTX-ZnONPs was found to be considerably enhanced at very low doses compared to that of free MTX. Moreover, ZnONPs alone significantly inhibited the cell viability of A549 cells at a much higher concentration compared to MTX-ZnONPs and MTX. Furthermore, the cytomorphology of A549 cells was characterized by cellular shrinkage and detachment from the surface in all the treatment groups. Similarly, A549 cells, in all the treatment groups, showed fragmented and condensed nuclei, indicating the initiation of apoptosis. Mitochondrial membrane potential (ψm) in A549 cells showed a gradual loss in all the treatment groups. Results of the qualitative and quantitative analyses depicted increased reactive oxygen species (ROS) levels in A549 cells. The results of the caspase activity assay showed that MTX-ZnONPs andfree MTX caused significant activation of caspase-9, -8, and -3 in A549 cells; however, the effect of MTX-ZnONPs was more profound at very low doses compared to that of free MTX. Thus, our results showed high efficacy of MTX-ZnONPs, suggesting efficient intracellular delivery of the drug by ZnONPs as nanocarriers.

Polypropylene sulphide coating on magnetic nanoparticles as a novel platform for excellent biocompatible, stimuli-responsive smart magnetic nanocarriers for cancer therapeutics

Magnetic nanoparticle (MNP) delivery systems are promising for targeted drug delivery, imaging, and chemo-hyperthermia of cancer; however, their uses remain limited primarily due to their toxicity associated with reactive oxygen species (ROS) generation, targeted delivery, and biodegradation. Attempts employing polymer coatings to minimize the toxicity, along with other challenges, have had limited success. We designed a novel yet generic 'one-for-all' polypropylene sulphide (PPS) coated magnetic nano-delivery system (80 ± 15 nm) as a multi-faceted approach for significant biocompatibility improvement, loading of multiple drugs, ROS-responsive delivery, and combined chemo-hyperthermia therapy for biomedical applications. Three distinct MNP systems (15 ± 1 nm) were fabricated, coated with PPS polymer, and investigated to validate our hypothesis and design. Simultaneous degradation of MNPs and PPS coatings with ROS-scavenging characteristics boosted the biocompatibility of MNPs 2-3 times towards non-cancerous fibroblasts (NIH3T3) and human epithelial cells (HEK293). In an alternating magnetic field, PPS-MNPs (MnFe) had the strongest heating characteristics (SAR value of 240 W g^-1). PPS-MNP drug-loaded NPs were efficiently internalised into cells and released 80% of the drugs under tumor microenvironment-mimicking (pH 5-7, ROS) conditions, and demonstrated effective chemo-hyperthermia (45 °C) application for breast cancer cells with 95% cell death in combined treatment vs. 55% and 30% cell death in only hyperthermia and chemotherapy respectively.

Evolution of Gold and Iron Oxide Nanoparticles in Conjugates with Methotrexate: Synthesis and Anticancer Effects

Au and Fe nanoparticles and their conjugates with the drug methotrexate were obtained by an environmentally safe method of metal-vapor synthesis (MVS). The materials were characterized by transmission and scanning electron microscopy (TEM, SEM), X-ray photoelectron spectroscopy (XPS), and small-angle X-ray scattering using synchrotron radiation (SAXS). The use of acetone as an organic reagent in the MVS makes it possible to obtain Au and Fe particles with an average size of 8.3 and 1.8 nm, respectively, which was established by TEM. It was found that Au, both in the NPs and the composite with methotrexate, was in the Au⁰, Au⁺ and Au³⁺ states. The Au 4f spectra for Au-containing systems are very close. The effect of methotrexate was manifested in a slight decrease in the proportion of the Au⁰ state-from 0.81 to 0.76. In the Fe NPs, the main state is the Fe³⁺ state, and the Fe²⁺ state is also present in a small amount. The analysis of samples by SAXS registered highly heterogeneous populations of metal nanoparticles coexisting with a wide proportion of large aggregates, the number of which increased significantly in the presence of methotrexate. For Au conjugates with methotrexate, a very wide asymmetric fraction with sizes up to 60 nm and a maximum of ~4 nm has been registered. In the case of Fe, the main fraction consists of particles with a radius of 4.6 nm. The main fraction consists of aggregates up to 10 nm. The size of the aggregates varies in the range of 20-50 nm. In the presence of methotrexate, the number of aggregates increases. The cytotoxicity and anticancer activity of the obtained nanomaterials were determined by MTT and NR assays. Fe conjugates with methotrexate showed the highest toxicity against the lung adenocarcinoma cell line and Au nanoparticles loaded with methotrexate affected the human colon adenocarcinoma cell line. Both conjugates displayed lysosome-specific toxicity against the A549 cancer cell line after 120 h of culture. The obtained materials may be promising for the creation of improved agents for cancer treatment.

Aspartic Acid Stabilized Iron Oxide Nanoparticles for Biomedical Applications

Aspartic acid stabilized iron oxide nanoparticles (A-IONPs) with globular shape and narrow size distribution were prepared by the co-precipitation method in aqueous medium. A quantum-mechanical approach to aspartic acid optimized structure displayed negative charged sites, relatively high dipole moment, and hydrophilicity, which recommended it for interaction with iron cations and surrounding water electrical dipoles. A-IONPs were characterized by TEM, XRD, ATR-FTIR, EDS, DSC, TG, DLS, NTA, and VSM techniques. Theoretical study carried out by applying Hartree-Fock and density functional algorithms suggested that some aspartic acid properties related to the interaction can develop with nanoparticles and water molecules. The results of experimental investigation showed that the mean value of particle physical diameters was 9.17 ± 2.2 nm according to TEM image analysis, the crystallite size was about 8.9 nm according to XRD data, while the magnetic diameter was about 8.8 nm, as was determined from VSM data interpretation with Langevin's theory. The A-IONP suspension was characterized by zeta-potential of about -11.7 mV, while the NTA investigation revealed a hydrodynamic diameter of 153.9 nm. These results recommend the A-IONP suspension for biomedical applications.

Approaches on Ferrofluid Synthesis and Applications: Current Status and Future Perspectives

Ferrofluids are colloidal suspensions of iron oxide nanoparticles (IONPs) within aqueous or nonaqueous liquids that exhibit strong magnetic properties. These magnetic properties allow ferrofluids to be manipulated and controlled when exposed to magnetic fields. This review aims to provide the current scope and research opportunities regarding the methods of synthesis of nanoparticles, surfactants, and carrier liquids for ferrofluid production, along with the rheology and applications of ferrofluids within the fields of medicine, water treatment, and mechanical engineering. A ferrofluid is composed of IONPs, a surfactant that coats the magnetic IONPs to prevent agglomeration, and a carrier liquid that suspends the IONPs. Coprecipitation and thermal decomposition are the main methods used for the synthesis of IONPs. Despite the fact that thermal decomposition provides precise control on the nanoparticle size, coprecipitation is the most used method, even when the oxidation of iron can occur. This oxidation alters the ratio of maghemite/magnetite, influencing the magnetic properties of ferrofluids. Strategies to overcome iron oxidation have been proposed, such as the use of an inert atmosphere, adjusting the Fe(II) and Fe(III) ratio to 1:2, and the exploration of other metals with the oxidation state +2. Surfactants and carrier liquids are chosen according to the ferrofluid application to ensure stability. Hence, a compatible carrier liquid (polar or nonpolar) is selected, and then, a surfactant, mainly a polymer, is embedded in the IONPs, providing a steric barrier. Due to the variety of surfactants and carrier liquids, the rheological properties of ferrofluids are an important response variable evaluated when synthesizing ferrofluids. There are many reported applications of ferrofluids, including biosensing, medical imaging, medicinal therapy, magnetic nanoemulsions, and magnetic impedance. Other applications include water treatment, energy harvesting and transfer, and vibration control. To progress from synthesis to applications, research is still ongoing to ensure control of the ferrofluids' properties.

Nanoparticles for Magnetic Heating: When Two (or More) Is Better Than One

The increasing use of magnetic nanoparticles as heating agents in biomedicine is driven by their proven utility in hyperthermia therapeutic treatments and heat-triggered drug delivery methods. The growing demand of efficient and versatile nanoheaters has prompted the creation of novel types of magnetic nanoparticle systems exploiting the magnetic interaction (exchange or dipolar in nature) between two or more constituent magnetic elements (magnetic phases, primary nanoparticles) to enhance and tune the heating power. This process occurred in parallel with the progress in the methods for the chemical synthesis of nanostructures and in the comprehension of magnetic phenomena at the nanoscale. Therefore, complex magnetic architectures have been realized that we classify as: (a) core/shell nanoparticles; (b) multicore nanoparticles; (c) linear aggregates; (d) hybrid systems; (e) mixed nanoparticle systems. After a general introduction to the magnetic heating phenomenology, we illustrate the different classes of nanoparticle systems and the strategic novelty they represent. We review some of the research works that have significantly contributed to clarify the relationship between the compositional and structural properties, as determined by the synthetic process, the magnetic properties and the heating mechanism.

Magnetic Particle Spectroscopy with One-Stage Lock-In Implementation for Magnetic Bioassays with Improved Sensitivities

In recent years, magnetic particle spectroscopy (MPS) has become a highly sensitive and versatile sensing technique for quantitative bioassays. It relies on the dynamic magnetic responses of magnetic nanoparticles (MNPs) for the detection of target analytes in the liquid phase. There are many research studies reporting the application of MPS for detecting a variety of analytes including viruses, toxins, nucleic acids, and so forth. Herein, we report a modified version of the MPS platform with the addition of a one-stage lock-in design to remove the feedthrough signals induced by external driving magnetic fields, thus capturing only MNP responses for improved system sensitivity. This one-stage lock-in MPS system is able to detect as low as 781 ng multi-core Nanomag50 iron oxide MNPs (micromod Partikeltechnologie GmbH) and 78 ng single-core SHB30 iron oxide MNPs (Ocean NanoTech). We first demonstrated the performance of this MPS system for bioassay-related applications. Using the SARS-CoV-2 spike protein as a model, we have achieved a detection limit of 125 nM (equal to 5 pmole) for detecting spike protein molecules in the liquid phase. In addition, using a streptavidin-biotin binding system as a proof-of-concept, we show that these single-core SHB30 MNPs can be used for Brownian relaxation-based bioassays while the multi-core Nanomag50 cannot be used. The effects of MNP amount on the concentration-dependent response profiles for detecting streptavidin were also investigated. Results show that by using a lower concentration/ amount of MNPs, concentration-response curves shift to a lower concentration/amount of target analytes. This lower concentration-response indicates the possibility of improved bioassay sensitivities by using lower amounts of MNPs.

Review on Recent Progress in Magnetic Nanoparticles: Synthesis, Characterization, and Diverse Applications

Diverse applications of nanoparticles (NPs) have revolutionized various sectors in society. In the recent decade, particularly magnetic nanoparticles (MNPs) have gained enormous interest owing to their applications in specialized areas such as medicine, cancer theranostics, biosensing, catalysis, agriculture, and the environment. Controlled surface engineering for the design of multi-functional MNPs is vital for achieving desired application. The MNPs have demonstrated great efficacy as thermoelectric materials, imaging agents, drug delivery vehicles, and biosensors. In the present review, first we have briefly discussed main synthetic methods of MNPs, followed by their characterizations and composition. Then we have discussed the potential applications of MNPs in different with representative examples. At the end, we gave an overview on the current challenges and future prospects of MNPs. This comprehensive review not only provides the mechanistic insight into the synthesis, functionalization, and application of MNPs but also outlines the limits and potential prospects.

Progress and prospects of magnetic iron oxide nanoparticles in biomedical applications: A review

Nanoscience has been considered as one of the most substantial research in modern science. The utilization of nanoparticle (NP) materials provides numerous advantages in biomedical applications due to their unique properties. Among various types of nanoparticles, the magnetic nanoparticles (MNPs) of iron oxide possess intrinsic features, which have been efficiently exploited for biomedical purposes including drug delivery, magnetic resonance imaging, Magnetic-activated cell sorting, nanobiosensors, hyperthermia, and tissue engineering and regenerative medicine. The size and shape of nanostructures are the main factors affecting the physicochemical features of superparamagnetic iron oxide nanoparticles, which play an important role in the improvement of MNP properties, and can be controlled by appropriate synthesis strategies. On the other hand, the proper modification and functionalization of the surface of iron oxide nanoparticles have significant effects on the improvement of physicochemical and mechanical features, biocompatibility, stability, and surface activity of MNPs. This review focuses on popular methods of fabrication, beneficial surface coatings with regard to the main required features for their biomedical use, as well as new applications.

Magnetic nanoparticles applied in targeted therapy and magnetic resonance imaging: crucial preparation parameters, indispensable pre-treatments, updated research advancements and future perspectives

Magnetic nanoparticles (MNPs) have attracted much attention in cancer treatment as carriers for drug delivery and imaging contrast agents due to their distinctive performances based on their magnetic properties and nanoscale structure. In this review, we aim to comprehensively dissect how the applications of MNPs in targeted therapy and magnetic resonance imaging are achieved and their specificities by focusing on the following aspects: (1) several important preparation parameters (pH, temperature, ratio of the reactive substances, etc.) that have crucial effects on the properties of MNPs, (2) indispensable treatments to improve the biocompatibility, stability, and targeting ability of MNPs and prolong their circulation time for biomedical applications, (3) the mechanism for MNPs to deliver and release medicine to the desired sites and be applied in magnetic hyperthermia as well as related updated research advancements, (4) comparatively promising research directions of MNPs in magnetic resonance imaging, and (5) perspectives in the further optimization of their preparations, pre-treatments and applications in cancer diagnosis and therapy.

Surface Engineered Iron Oxide Nanoparticles Generated by Inert Gas Condensation for Biomedical Applications

Despite the lifesaving medical discoveries of the last century, there is still an urgent need to improve the curative rate and reduce mortality in many fatal diseases such as cancer. One of the main requirements is to find new ways to deliver therapeutics/drugs more efficiently and only to affected tissues/organs. An exciting new technology is nanomaterials which are being widely investigated as potential nanocarriers to achieve localized drug delivery that would improve therapy and reduce adverse drug side effects. Among all the nanocarriers, iron oxide nanoparticles (IONPs) are one of the most promising as, thanks to their paramagnetic/superparamagnetic properties, they can be easily modified with chemical and biological functions and can be visualized inside the body by magnetic resonance imaging (MRI), while delivering the targeted therapy. Therefore, iron oxide nanoparticles were produced here with a novel method and their properties for potential applications in both diagnostics and therapeutics were investigated. The novel method involves production of free standing IONPs by inert gas condensation via the Mantis NanoGen Trio physical vapor deposition system. The IONPs were first sputtered and deposited on plasma cleaned, polyethylene glycol (PEG) coated silicon wafers. Surface modification of the cleaned wafer with PEG enabled deposition of free-standing IONPs, as once produced, the soft-landed IONPs were suspended by dissolution of the PEG layer in water. Transmission electron microscopic (TEM) characterization revealed free standing, iron oxide nanoparticles with size < 20 nm within a polymer matrix. The nanoparticles were analyzed also by Atomic Force Microscope (AFM), Dynamic Light Scattering (DLS) and NanoSight Nanoparticle Tacking Analysis (NTA). Therefore, our work confirms that inert gas condensation by the Mantis NanoGen Trio physical vapor deposition sputtering at room temperature can be successfully used as a scalable, reproducible process to prepare free-standing IONPs. The PEG- IONPs produced in this work do not require further purification and thanks to their tunable narrow size distribution have potential to be a powerful tool for biomedical applications.

Nanoparticle-based amelioration of drought stress and cadmium toxicity in rice via triggering the stress responsive genetic mechanisms and nutrient acquisition

Cadmium and drought are the most destructive of the abiotic stresses with negative consequences in terms of impaired metabolism, restricted nutrient use efficiency and disruptive photosynthesis of plants. The present study investigated the mitigation strategy of both aforementioned stresses by the application of iron oxide (IONPs) and hydrogel nanoparticles (HGNPs) simultaneously probably for the first time. IONPs were biofabricated by using a locally identified Bacillus strain RNT1, while HGNPs were produced chemically followed by the confirmation and characterization of both NPs through nanomaterials characterization techniques. Results of FTIR and XRD showed the capping of NPs by different functional groups together with their crystalline structure, respectively. SEM and TEM analysis showed the spherical shape along with the particle size ranging from 18 to 94 nm of both NPs, while EDS analysis confirmed the elemental purity of NPs. The results revealed that IONPs-treated rice plants increased biomass, antioxidant enzyme contents, photosynthesis efficiency, nutrient acquisition together with the decrease in reactive oxygen species and acropetal Cd translocation under normal and drought stress conditions as compared with control plants. Furthermore, the expression of the Cd transporter genes, OsHMA2, OsHMA3 and OsLCT1 were curtailed in NPs-treated rice plants under normal and drought stress conditions. The overall significance of the study lies in devising the NPs-based solutions of increasing heavy metal pollution and water availability challenges being faced the farmers around the world.

Magnetic Iron Oxide Nanoparticle (IONP) Synthesis to Applications: Present and Future

Iron oxides are chemical compounds which have different polymorphic forms, including γ-Fe2O3 (maghemite), Fe3O4 (magnetite), and FeO (wustite). Among them, the most studied are γ-Fe2O3 and Fe3O4, as they possess extraordinary properties at the nanoscale (such as super paramagnetism, high specific surface area, biocompatible etc.), because at this size scale, the quantum effects affect matter behavior and optical, electrical and magnetic properties. Therefore, in the nanoscale, these materials become ideal for surface functionalization and modification in various applications such as separation techniques, magnetic sorting (cells and other biomolecules etc.), drug delivery, cancer hyperthermia, sensing etc., and also for increased surface area-to-volume ratio, which allows for excellent dispersibility in the solution form. The current methods used are partially and passively mixed reactants, and, thus, every reaction has a different proportion of all factors which causes further difficulties in reproducibility. Direct active and complete mixing and automated approaches could be solutions to this size- and shape-controlled synthesis, playing a key role in its exploitation for scientific or technological purposes. An ideal synthesis method should be able to allow reliable adjustment of parameters and control over the following: fluctuation in temperature; pH, stirring rate; particle distribution; size control; concentration; and control over nanoparticle shape and composition i.e., crystallinity, purity, and rapid screening. Iron oxide nanoparticle (IONP)-based available clinical applications are RNA/DNA extraction and detection of infectious bacteria and viruses. Such technologies are important at POC (point of care) diagnosis. IONPs can play a key role in these perspectives. Although there are various methods for synthesis of IONPs, one of the most crucial goals is to control size and properties with high reproducibility to accomplish successful applications. Using multiple characterization techniques to identify and confirm the oxide phase of iron can provide better characterization capability. It is very important to understand the in-depth IONP formation mechanism, enabling better control over parameters and overall reaction and, by extension, properties of IONPs. This work provides an in-depth overview of different properties, synthesis methods, and mechanisms of iron oxide nanoparticles (IONPs) formation, and the diverse range of their applications. Different characterization factors and strategies to confirm phase purity in the IONP synthesis field are reviewed. First, properties of IONPs and various synthesis routes with their merits and demerits are described. We also describe different synthesis strategies and formation mechanisms for IONPs such as for: wustite (FeO), hematite (α-Fe2O3), maghemite (ɤ-Fe2O3) and magnetite (Fe3O4). We also describe characterization of these nanoparticles and various applications in detail. In conclusion, we present a detailed overview on the properties, size-controlled synthesis, formation mechanisms and applications of IONPs.

Gold, Silver and Iron Oxide Nanoparticles: Synthesis and Bionanoconjugation Strategies Aimed at Electrochemical Applications

Nanomaterials have revolutionized the sensing and biosensing fields, with the development of more sensitive and selective devices for multiple applications. Gold, silver and iron oxide nanoparticles have played a particularly major role in this development. In this review, we provide a general overview of the synthesis and characteristics of gold, silver and iron oxide nanoparticles, along with the main strategies for their surface functionalization with ligands and biomolecules. Finally, different architectures suitable for electrochemical applications are reviewed, as well as their main fabrication procedures. We conclude with some considerations from the authors' perspective regarding the promising use of these materials and the challenges to be faced in the near future.

Targeting kidneys by superparamagnetic allopurinol loaded chitosan coated nanoparticles for the treatment of hyperuricemic nephrolithiasis

PURPOSE

The major short coming of conventional therapy system is that they can't deliver the therapeutics specifically to a site within the body without producing nonspecific toxicity. Present research aimed at developing kidney targeted allopurinol (AP) loaded chitosan coated magnetic nanoparticles (A-MNPs) for the management of hyperuricemic nephropathy manifested in the form of nephrolithiasis.

METHODS

The work includes preparation of magnetic nanoparticles by chemical co-precipitation method and evaluation of the prepared batches for particle size analysis, Transmission electron microscopy, entrapment efficiency, in-vitro release study etc. Further, FTIR spectroscopy, X-ray diffraction, Differential Scanning Calorimetry, Vibrational sample magnetometer (VSM) and in-vivo animal studies were also performed.

RESULTS

VSM analysis demonstrates that the prepared nanoparticles exhibit superparamagnetic magnetic behaviour which was retained even after coating by chitosan. In-vivo studies of A-MNPs showed 19.07-fold increase in kidney uptake of AP as compared to serum post 2 h of administration in mice whereas no drug was detected in kidney and serum post 2 h administration of pure drug (free-form) indicating successful targeting to kidney as well as sustained release of AP from the formulated A-MNPs. The significant (p < 0.01) effectiveness of A-MNPs in management of hyperuricemic nephrolithiasis was observed through estimating pH and uric acid levels in urine and serum samples of mice. These findings were also confirmed by histological examination of isolated kidney samples.

CONCLUSION

Present investigation signifies that a simple external magnetic field is enough for targeting allopurinol to kidneys by formulating A-MNPs which further offers an effective approach for management of hyperuricemic nephrolithiasis. Graphical Abstract.

Succinylated heparin monolayer coating vastly increases superparamagnetic iron oxide nanoparticle T2 proton relaxivity

Superparamagnetic iron oxide nanoparticles (SPIONs) have a history of clinical use as contrast agents in T₂ weighted MRI, though relatively low T₂ relaxivity has caused them to fall out of favor as new faster MRI techniques have gained prominence. We demonstrate that SPIONs coated with a monolayer of succinylated heparin (Su-HP-SPIONs) exhibit over four-fold increased T₂ relaxivity (460 mM^-1 s^-1) as compared to the clinically approved SPION-based contrast agent Feridex (98.3 mM^-1 s^-1) due to greatly increased water interaction from increased hydrophilicity and thinner coating as supported by our proposed parametric model. In vivo, the performance increase of the Su-HP-SPIONs in T₂ MRI imaging of xenograft tumors is ten-fold that of our in-house synthesized Feridex analogue, due to better tumor localization from the smaller size imparted by the thinner coating. In addition to these significantly improved magnetic properties, the succinylated heparin coating also exhibits favorable synthetic reproducibility, solution stability, and biocompatibility. These findings demonstrate the untapped potential of SPIONs as possible high performance clinical T₂ contrast agents.

Synthesis, purification, and anticancer effect of magnetic Fe3O4-loaded poly (lactic-co-glycolic) nanoparticles of the natural drug tetrandrine

Here, we have successfully synthesised and purified multifunctional PLGA-based nanoparticles by the co-encapsulation of an anticancer drug (tetrandrine) and a magnetic material (Fe₃O₄). The obtained Tet-Fe₃O₄-PLGA NPs had a uniform spherical shape with a particle size of approximately 199 nm and a negative surface charge of -18.0 mV, displaying a high encapsulation efficiency. Furthermore, TEM studies provided representative images of the purification process of the magnetic nanoparticles with MACS^® technology. The MFM and VSM results indicated that both the Fe₃O₄ NPs and Tet-Fe₃O₄-PLGA NPs were superparamagnetic. The DSC spectrum demonstrated that Tet was successfully encapsulated within the PLGA-based nanoparticles. Significantly, the release studies revealed NPs had a relatively slower release rate than free Tet after 8 h's initial burst release, which had decreased from 98% to 65% after 24 h. In vitro cellular studies revealed that NPs could effectively penetrate into A549 cells and A549 multicellular spheroids to exert cytotoxicity, displaying a significantly high anti-proliferation effect. Moreover, western blot demonstrated that the co-loaded NPs had a higher anticancer activity by injuring lysosomes to activate the mitochondria pathway and induce A549 cell apoptosis. The magnetic characteristics and high anticancer activity support the use of Tet/Fe₃O₄ co-loaded PLGA-based nanoparticles as a promising strategy in the treatment of lung cancer.

Permeation Efficacy of a Transdermal Vehicle with Steroidal Hormones and Nonsteroidal Anti-inflammatory Agents as Model Drugs

BACKGROUND

Transdermal delivery is an alternative route for the administration of drugs. However, it requires the development of vehicles that allow the drugs to cross the layers of the skin and reach the systemic circulation.

OBJECTIVE

In this study, a new transdermal vehicle was evaluated using progesterone, estradiol, estradiol + estriol (Biest) and ketoprofen administered as model drugs.

METHODS

To evaluate the ex vivo permeation of the drugs, the Franz vertical diffusion cell with human skin was used.

RESULTS

After 24 h, the vehicle was able to deliver 18.32 µg/cm2 of progesterone and 92.07 µg/cm2 of ketoprofen through the skin to the receptor medium. The permeation percentages were 91%, 78.8%, 48.5%, 73.2%, and 63.6%, respectively, for estradiol, estradiol (Biest), estriol (Biest), progesterone and ketoprofen. For all drugs, sufficient amounts were delivered to achieve a systemic effect, and it was also possible to decrease the amount of emulsion applied.

CONCLUSION

Thus, the vehicle demonstrated a high performance and the possibility of it being used for drugs that present difficulties in regards to administration by the transdermal route.

Antimicrobial magnetic nanoparticles based-therapies for controlling infectious diseases

In the last years, the antimicrobial resistance against antibiotics has become a serious health issue, arise as global threat. This has generated a search for new strategies in the progress of new antimicrobial therapies. In this context, different nanosystems with antimicrobial properties have been studied. Specifically, magnetic nanoparticles seem to be very attractive due to their relatively simple synthesis, intrinsic antimicrobial activity, low toxicity and high versatility. Iron oxide NPs (IONPs) was authorized by the World Health Organization for human used in biomedical applications such as in vivo drug delivery systems, magnetic guided therapy and contrast agent for magnetic resonance imaging have been widely documented. Furthermore, the antimicrobial activity of different magnetic nanoparticles has recently been demonstrated. This review elucidates the recent progress of IONPs in drug delivery systems and focuses on the treatment of infectious diseases and target the possible detrimental biological effects and associated safety issues.

Schiff base-containing dextran nanogel as pH-sensitive drug delivery system of doxorubicin: Synthesis and characterization

Stimuli-responsive hydrogels have been widely researched as carrier systems, due to their excellent biocompatibility and responsiveness to external physiologic environment factors. In this study, dextran-based nanogel with covalently conjugated doxorubicin (DOX) was developed via Schiff base formation using the inverse microemulsion technique. Since the Schiff base linkages are acid-sensitive, drug release profile of the DOX-loaded nanogel would be pH-dependent. In vitro drug release studies confirmed that DOX was released much faster under acidic condition (pH 2.0, 5.0) than that at pH 7.4. Approximately 66, 28, and 9% of drug was released in 72 h at pH 2.0, 5.0, and 7.4, respectively. Cell uptake by the human breast cancer cell (MCF-7) demonstrated that the DOX-loaded dextran nanogel could be internalized through endocytosis and distributed in endocytic compartments inside tumor cells. These results indicated that the Schiff base-containing nanogel can serve as a pH-sensitive drug delivery system. And the presence of multiple aldehyde groups on the nanogel are available for further conjugations of targeting ligands or imaging probes.

Preparation and Evaluation of Multifunctional Autofluorescent Magnetic Nanoparticle-Based Drug Delivery Systems Against Mammary Cancer

The Fe₃O₄@C@NaYF₄:Yb,Er nanocarriers of multifunction were synthesized. The mitoxantrone was selected as model drug, and these nanoparticles have high drug loading (0.63 mg/mg). The temperature of Fe₃O₄@C@NaYF₄:Yb,Er in water reached 60°C with 808 nm irritation (2.5 W/cm²). The cumulative release of these nano drug carriers significantly increased because of the increase in temperature, and the 4T1 cell growth inhibition rates were 59.15%, almost 2.25-fold higher than mitoxantrone group (p <0.05). Because the nanoparticles had autofluorescence under 808 nm irritation, the nanocarriers could be traced in both in vitro and in vivo studies. Based on magnetic field, the fluorescence signal of these nano drug carriers could be observed at tumor region during 2-9 h in vivo study. The nanocarriers with magnetic and 808 nm laser group, tumor growth inhibition rate achieved almost 83.14%. These nanoparticles are an outstanding potential carrier for antitumor drugs, which can improve curative effect for tumor while reducing toxicity.

Production of biological nanoparticles from bovine serum albumin as controlled release carrier for curcumin delivery

This study described a curcumin (CUR) loaded bovine serum albumin nanoparticles (BSA@CUR NPs), which could solubilize the poorly water-soluble drug and increase the therapeutic efficacy of the drug. BSA@CUR NPs were synthesized by a simple coacervation procedure. The resultant BSA@CUR NPs showed a spherical shape, with a diameter of 92.59±16.75nm (mean ± SD) nm and a ζ-potential of - 9.19mV. The in vitro drug release study of CUR showed a sustained and controlled release pattern. Cellular toxicity of BSA NPs was also investigated on HFF2 cell lines. Additionally, a hemolysis test of as prepared NPs were performed for investigation of hemocompatibility. Hemolysis assay and cytotoxicity study results on HFF-2 cell line show that as prepared BSA NPs are biocompatible. The in vitro anticancer activity of the BSA@CUR NPs were performed by MTT assay on MCF-7 cancer cells. These results suggest that BSA@CUR NPs are a new drug delivery system for cancer therapy.

PAMAM-modified citric acid-coated magnetic nanoparticles as pH sensitive biocompatible carrier against human breast cancer cells

Denderimer-modified magnetic nanoparticles are a promising drug delivery nanosystem which can improve the therapeutic efficacy of chemotherapy drugs and can also be beneficial as magnetic resonance (MR) images contrast agent. The present study introduces the preparation and characterization of the potential therapeutic efficiency of curcumin (CUR)-loaded denderimer-modified citric acid coated Fe₃O₄ NPs. Polyamidoamine (PAMAM, generation G₅) was used to encapsulate citric acid coated Fe₃O₄ nanoparticles. The successful preparation of CUR-loaded nanocarriers were confirmed by X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM) techniques. The loading capacity and encapsulation efficiency of CUR molecules were 12 ± 0.03% and 45.58 ± 0.41%, respectively. The anticancer effect of void CUR and CUR-loaded nanocarriers were compared to each other by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on treated MCF-7 cell line. It can be concluded that application of nanoparticles can be more effective strategy for controlled and slow release of CUR in human breast cancer treatment.

Bovine Serum Albumin (BSA) coated iron oxide magnetic nanoparticles as biocompatible carriers for curcumin-anticancer drug

The bovine serum albumin-coated magnetic nanoparticles (F@BSA NPs) were prepared as curcumin (CUR) carriers through desolvation and chemical co-precipitation process. The characteristics of CUR loaded F@BSA NPs (F@BSA@CUR NPs) were determined by X-ray diffraction (XRD), thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and vibrating-sampling magnetometry (VSM) techniques. It was found that the synthesized F@BSA@CUR NPs were spherical in shape with an average size of 56 ± 11.43 nm (mean ± SD (n = 33)), ζ-potential of -10.1 mV, and good magnetic responsivity. Meanwhile, the drug content of the nanoparticles was 6.88%. These F@BSA@CUR NPs also demonstrated sustained release of CUR at 37 °C in different buffer solutions. Cellular toxicity of F@BSA@CUR NPs was studied on HFF2 cell line. Also, the cytotoxicity of F@BSA@CUR NPs towards MCF-7 breast cancer cells was investigated. The results revealed that F@BSA@CUR NPs have significant cytotoxicity activity on MCF-7 cell line.

In vitro and in vivo delivery of atorvastatin: A comparative study of anti-inflammatory activity of atorvastatin loaded copolymeric micelles

Statins have been shown to exert ‘pleiotropic effects’ independent of their cholesterol lowering actions that include anti-inflammatory properties. In this study we synthesized mono methoxy poly (ethylene glycol)–poly (ε-caprolactone) (mPEG-PCL) di block copolymers. The structure of the copolymers was characterized by H nuclear magnetic resonance, Fourier-transform infrared spectroscopy, differential scanning calorimetry and gel permeation chromatography techniques. In this method, atorvastatin was encapsulated within micelles through a single-step nano-precipitation method, leading to the formation of atorvastatin-loaded mPEG-PCL (atorvastatin/mPEG-PCL) micelles. The resulting micelles were characterized further by various techniques such as dynamic light scattering and atomic force microscopy. In this study the anti-inflammatory activity of atorvastatin and atorvastatin/mPEG-PCL micelles on acute models of inflammation are analyzed, to compare the effect of indometacin in rats. Carrageenan induces rat paw edema; six animals of each group (10 groups) received indometacin, atorvastatin, and atorvastatin/mPEG-PCL micelles orally 1, 6, 12 and 24 h before carrageenan injection in paw. The paw edema thickness measured at 1, 2, 3 and 4 h after injection and percentage inhibition of edema in various groups were calculated. The results showed that the zeta potential of micelles was about −16.6 mV and the average size was 81.7 nm. Atorvastatin was encapsulated into mPEG-PCL micelles with loading capacity of 14.60 ± 0.96% and encapsulation efficiency of 62.50 ± 0.84%. Atorvastatin and atorvastatin/mPEG-PCL micelles showed significant anti-inflammatory activity in the present study. The anti-inflammatory activity of atorvastatin and atorvastatin/mPEG-PCL micelles was significant in comparison with indometacin. Atorvastatin/mPEG-PCL micelles showed more anti-inflammatory activity than atorvastatin. This study revealed the anti-inflammatory activity of atorvastatin and atorvastatin/mPEG-PCL micelles and suggested the statins have a potential inflammatory activity along with its lipid lowering properties. Contrary to anti-inflammatory effects, the pro-inflammatory responses are independent of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibition and can be mediated directly by atorvastatin.

Preparation of magnetic albumin nanoparticles via a simple and one-pot desolvation and co-precipitation method for medical and pharmaceutical applications

In this study, iron oxide magnetic bovine serum albumin core-shell nanoparticles (BSA coated IONPs) with narrow particle size distribution were synthesized under one-pot reaction via the desolvation and chemical co-precipitation method. Functionalized IONPs were characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM) techniques. Furthermore, vibrating sample magnetometer (VSM) analysis show these nanoparticles (NPs) have an excellent magnetic properties. Cellular toxicity of IONPs was also investigated on HFF2 cell lines. Additionally, a hemolysis test of as prepared core-shell NPs were performed. The presence of albumin as a biomolecule coating on the surface of IONPs showed an improving effect to reduce the cytotoxicity. The properties of the designed NPs propose the BSA coated IONPs as a promising candidate for multifunctional biomedical applications.