Types Of Iron Oxide Nanoparticles Research Articles

Radiolabeled iron oxide nanoparticles functionalized with PSMA/BN ligands for dual-targeting of prostate cancer

IntroductionProstate cancer (PCa) is the second most frequent cancer diagnosis in men and the fifth leading cause of death worldwide. Prostate Specific Membrane Antigen (PSMA) and Gastrin Releasing Peptide (GRP) receptors are overexpressed in PCa. In this study, we have developed iron oxide nanoparticles (IONs) functionalized with the Prostate Specific Membrane Antigen (PSMA) and Gastrin Releasing Peptide (GRP) ligands for dual targeting of Prostate cancer.MethodsIONs were developed with a thin silica layer on their surface with MPTES (carrying -SH groups, IONs-SH), and they were coupled either with a pharmacophore targeting PSMA (IONs-PSMA) or with bombesin peptide (IONs-BN), targeting GRP receptors, or with both (IONs-PSMA/BN). The functionalized IONs were characterized for their size, zeta potential, and efficiency of functionalization using dynamic light scattering (DLS) and Fourier-Transform Infrared Spectroscopy (FT-IR). All the aforementioned types of IONs were radiolabeled directly with Technetium-99m (99mTc) and evaluated for their radiolabeling efficiency, stability, and binding ability on two different PCa cell lines (PC3 and LNCaP).Results and DiscussionThe MTT assay demonstrated low toxicity of the IONs against PC3 and LNCaP cells, while the performed wound-healing assay further proved that these nanostructures did not affect cellular growth mechanisms. The observed hemolysis ratio after co-incubation with red blood cells was extremely low. Furthermore, the 99mTc-radiolabeled IONs showed good stability in human serum, DTPA, and histidine, and high specific binding rates in cancer cells, supporting their future utilization as potential diagnostic tools for PCa with Single Photon Emission Computed Tomography (SPECT) imaging.

Functionalization and characterization of iron oxide nanoparticles recovered from acid mine drainage and application in the enhanced oil recovery

Oil is one of the most intensively used energy sources in the world and, as a fossil fuel, it is a finite resource. Different methods have been explored to increase oil recovery from mature fields, particularly using enhanced oil recovery (EOR) with the help of nanofluids. This study performed EOR tests using iron oxide nanoparticles added to brine and sodium dodecyl sulfate solutions. Three types of iron oxide nanoparticles were examined: commercial (IO), derived from the acid drainage of an underground coal mine (SIO), and temperature-sensitive functionalized (TSIO). The nanoparticles were well characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, high-resolution X-ray photoelectron spectroscopy, and transmission electron microscopy. The nanofluids were evaluated through dynamic light scattering measurements and determination of the viscosity, turbidity, contact angle and surface tension. There was not significant variation in the surface tension of the samples, which ranged between 25.46 and 28.28 mN m−1. However, the contact angle exhibited notable fluctuations depending on the nanoparticles concentration, ranging from 7.39° to 24.43°. Furthermore, the zeta potential suggests that the stability of the nanofluid samples falls within the moderate to medium range. An improvement in oil recovery reached 10% with the commercial nanoparticles (0.50 wt%), followed by 8.5% using the synthesized (0.25 wt%) and 7.5% using the functionalized (0.25 wt%). Moreover, all nanofluids showed good stability for up to 30 days, and their viscosity showed a direct relationship with the enhancement in oil recovery.

Combined surface functionalization of MSC membrane and PDA inhibits neurotoxicity induced by Fe3O4 in mice based on apoptosis and autophagy through the ASK1/JNK signaling pathway.

The extensive utilization of iron oxide nanoparticles in medical and life science domains has led to a substantial rise in both occupational and public exposure to these particles. The potential toxicity of nanoparticles to living organisms, their impact on the environment, and the associated risks to human health have garnered significant attention and come to be a prominent area in contemporary research. The comprehension of the potential toxicity of nanoparticles has emerged as a crucial concern to safeguard human health and facilitate the secure advancement of nanotechnology. As nanocarriers and targeting agents, the biocompatibility of them determines the use scope and application prospects, meanwhile surface modification becomes an important measure to improve the biocompatibility. Three different types of iron oxide nanoparticles (Fe3O4, Fe3O4@PDA and MSCM-Fe3O4@PDA) were injected into mice through the tail veins. The acute neurotoxicity of them in mice was evaluated by measuring the levels of autophagy and apoptosis in the brain tissues. Our data revealed that iron oxide nanoparticles could cause nervous system damage by regulating the ASK1/JNK signaling pathway. Apoptosis and autophagy may play potential roles in this process. Exposure to combined surface functionalization of mesenchymal stem cell membrane and polydopamine showed the neuroprotective effect and may alleviate brain nervous system disorders.

Fluorescent Microscopy of Hot Spots Induced by Laser Heating of Iron Oxide Nanoparticles

Determination of the iron oxide nanoparticles (IONPs) local temperature during laser heating is important in the aspect of laser phototherapy. We have carried out theoretical modeling of IONPs local electromagnetic (EM) field enhancement and heating under the laser action near individual IONPs and ensembles of IONPs with different sizes, shapes and chemical phases. For experimental determination of IONPs temperature, we used fluorescence thermometry with rhodamine B (RhB) based on its lifetime. Depending on the IONPs shape and their location in space, a significant change in the spatial distribution of the EM field near the IONPs surface is observed. The local heating of IONPs in an ensemble reaches sufficiently high values; the relative change is about 35 °C for Fe2O3 NPs. Nevertheless, all the studied IONPs water colloids showed heating by no more than 10 °C. The heating temperature of the ensemble depends on the thermal conductivity of the medium, on which the heat dissipation depends. During laser scanning of a cell culture incubated with different types of IONPs, the temperature increase, estimated from the shortening of the RhB fluorescence lifetime, reaches more than 100 °C. Such “hot spots” within lysosomes, where IONPs predominantly reside, lead to severe cellular stress and can be used for cell therapy.

Effect of nanoparticles synthesized from green extracts on dark fermentative biohydrogen production

Research on the production of nanoparticles with sustainable methods using different leaf extracts as a reducing agent has gained momentum. In this study, green synthesis of two types of iron oxide nanoparticles were produced to investigate the impact of nanoparticles on bio-hydrogen yield. Olive leaf extract and microalgae extract were used as reducing agents for production. The synthesized nanoparticles were characterized via SEM, EDX, XRD and UV–Visible spectrum analyses. The nanoparticles have a stable appearance and mean particle sizes of 90.26 and 124.68 nm. Iron oxide nanoparticles produced from olive leaf extract were more effective in dark fermentation. Dark fermentation yields by Clostridium sp. were assessed utilizing various proportions of generated two types of nanoparticles (50–400 mg/L). The addition of 200 mg/L olive leaf extract-based iron oxide nanoparticles and 300 mg/L microalgae extract-based iron oxide nanoparticles enhanced the hydrogen production capacity by 41% and 28%, respectively.

Iron Oxide Nanoparticles Combined with Static Magnetic Fields in Bone Remodeling.

Iron oxide nanoparticles (IONPs) are extensively used in bone-related studies as biomaterials due to their unique magnetic properties and good biocompatibility. Through endocytosis, IONPs enter the cell where they promote osteogenic differentiation and inhibit osteoclastogenesis. Static magnetic fields (SMFs) were also found to enhance osteoblast differentiation and hinder osteoclastic differentiation. Once IONPs are exposed to an SMF, they become rapidly magnetized. IONPs and SMFs work together to synergistically enhance the effectiveness of their individual effects on the differentiation and function of osteoblasts and osteoclasts. This article reviewed the individual and combined effects of different types of IONPs and different intensities of SMFs on bone remodeling. We also discussed the mechanism underlying the synergistic effects of IONPs and SMFs on bone remodeling.

Synthesis of Magnetite Nanoparticles through a Lab-On-Chip Device.

Magnetite nanoparticles (MNPs) represent one of the most intensively studied types of iron oxide nanoparticles in various fields, including biomedicine, pharmaceutics, bioengineering, and industry. Since their properties in terms of size, shape, and surface charge significantly affects their efficiency towards the envisaged application, it is fundamentally important to develop a new synthesis route that allows for the control and modulation of the nanoparticle features. In this context, the aim of the present study was to develop a new method for the synthesis of MNPs. Specifically, a microfluidic lab-on-chip (LoC) device was used to obtain MNPs with controlled properties. The study investigated the influence of iron precursor solution concentration and flowed onto the final properties of the nanomaterials. The synthesized MNPs were characterized in terms of size, morphology, structure, composition, and stability. Results proved the formation of magnetite as a single mineral phase. Moreover, the uniform spherical shape and narrow size distribution were demonstrated. Optimal characteristics regarding MNPs crystallinity, uniformity, and thermal stability were obtained at higher concentrations and lower flows. In this manner, the potential of the LoC device is a promising tool for the synthesis of nanomaterials by ensuring the necessary uniformity for all final applications.

Iron Oxide Nanoparticles Synthesized Via Green Tea Extract for Doxorubicin Delivery

Background:: Due to the limitation of conventional cancer treatment using chemotherapy, the nanoparticle therapeutics have shown enhanced efficacy with alleviating side effects. Objective:: The aim of this study was to prepare the superparamagnetic iron oxide nanoparticles (TC- SPION) for doxorubicin (DOX) loading and delivery. Methods:: Here, we reported a simple green strategy to fabricate T-C-SPION using green tea extract and citric acid. Also, the anti-cancer drug, DOX, was used as a model drug to fabricate DOX-loaded nanoparticles. Results:: The formed T-C-SPION nanoparticles were spherical with a diameter of 23.8 ± 0.8 nm, as confirmed by Transmission Electron Microscopy (TEM). Besides, Dynamic Light Scattering (DLS) revealed that the prepared nanoparticles were water-dispersible and stable while stored in water for 6 weeks. The CCK-8 assay showed T-C-SPION to have a good cytocompatibility using different iron concentrations (10 ~ 120 ug/mL). Furthermore, T-C-SPION had a higher DOX encapsulation efficiency (Eencaps), around 43.2 ± 1.8 %, which resulted in a lagged release profile of DOX, compared to other types of iron oxide nanoparticles using green tea or citric acid alone. Next, cell viability assay indicated that T-C-SPION with a higher Eencaps showed superior and sustained cytotoxicity compared to the control group. Conclusion:: The developed iron oxide nanoparticles synthesized by green tea extract and citric acid in this paper could be considered as a potential drug carrier for cancer therapy applications.

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

The use of magnetism in medicine has changed dramatically since its first application by the ancient Greeks in 624 BC. Now, by leveraging magnetic nanoparticles, investigators have developed a range of modern applications that use external magnetic fields to manipulate biological systems. Drug delivery systems that incorporate these particles can target therapeutics to specific tissues without the need for biological or chemical cues. Once precisely located within an organism, magnetic nanoparticles can be heated by oscillating magnetic fields, which results in localized inductive heating that can be used for thermal ablation or more subtle cellular manipulation. Biological imaging can also be improved using magnetic nanoparticles as contrast agents; several types of iron oxide nanoparticles are US Food and Drug Administration (FDA)-approved for use in magnetic resonance imaging (MRI) as contrast agents that can improve image resolution and information content. New imaging modalities, such as magnetic particle imaging (MPI), directly detect magnetic nanoparticles within organisms, allowing for background-free imaging of magnetic particle transport and collection. “Lab-on-a-chip” technology benefits from the increased control that magnetic nanoparticles provide over separation, leading to improved cellular separation. Magnetic separation is also becoming important in next-generation immunoassays, in which particles are used to both increase sensitivity and enable multiple analyte detection. More recently, the ability to manipulate material motion with external fields has been applied in magnetically actuated soft robotics that are designed for biomedical interventions. In this review article, the origins of these various areas are introduced, followed by a discussion of current clinical applications, as well as emerging trends in the study and application of these materials.

Non-magnetic shell coating of magnetic nanoparticles as key factor of toxicity for cancer cells in a low frequency alternating magnetic field

This work is devoted to studying the effects of non-magnetic shell coating on nanoparticles in a low frequency alternating magnetic field (LF AMF) on tumor cells in vitro. Two types of iron oxide nanoparticles with the same magnetic core with and without silica shells were synthesized. Nanoparticles with silica shells significantly decreased the viability of PC3 cancer cells in a low frequency alternating magnetic field according to the cytotoxicity test, unlike uncoated nanoparticles. We showed that cell death results from the intracellular membrane integrity failure, and the calcium ions concentration increase with the subsequent necrosis. Transmission electron microscopy images showed that the uncoated silica nanoparticles are primarily found in an aggregated form in cells. We believe that uncoated nanoparticles lose their colloidal stability in an acidic endosomal environment after internalization into the cell due to surface etching and the formation of aggregates. As a result, they encounter high endosomal macromolecular viscosity and become unable to rotate efficiently. We assume that effective rotation of nanoparticles causes cell death. In turn, silica shell coating increases nanoparticles stability, preventing aggregation in endosomes. Thus, we propose that the colloidal stability of magnetic nanoparticles inside cells is one of the key factors for effective magneto-mechanical actuation.

Self-heating properties of iron oxide nanoparticles prepared at room temperature via ultrasonic-assisted co-precipitation process

ABSTRACT Preparation of iron oxide nanoparticles by a simple and environmentally friendly technique with high hyperthermia performance is highly desirable for biomedical application. These can potentially develop room temperature nanoparticles through the ultrasonic-assisted co-precipitation process. In this work, two types of iron oxide nanoparticles, un-coated iron oxide (IONPs) and coated iron oxide nanoparticles with tetraethoxysilane (IONPs-TEOS), were prepared at room temperature via ultrasonic-assisted co-precipitation process. The prepared nanoparticles were characterized using multiple techniques, such as Fourier transform infrared spectroscopy (FTIR), Thermal gravimetric analysis (TGA), vibrating sample magnetometer (VSM), dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), and X-ray diffraction (XRD). Self-heating properties and heating efficiency of the prepared nanoparticles were investigated under an alternative magnetic field in the function of carriers’ viscosity (water and ethanol) and induction time (0–6 minutes). It was found that the highest specific absorption rate (SAR) value for IONPs was 22.9 W/g when using water as a carrier. The viscosity affects the heating properties by changing the carrier through a Brownian mechanism and thus causes a significant SAR. Brownian relaxation is hindered by the particle’s hydrodynamic volume and the viscosity that tends to inhibit the particle rotation in the medium. Hence, the prepared room temperature iron oxide nanoparticles by this route can be applicable as hyperthermic agents for biomedical applications.

Biomaterial-Modified Magnetic Nanoparticles γ-Fe2O3, Fe3O4 Used to Improve the Efficiency of Hyperthermia of Tumors in HepG2 Model

The main treatments for cancer recorded to date include chemotherapy, radiotherapy, and surgery. Although we have achieved great success in treating certain types of tumors, there are still many incurable even with the help of modern treatments. Currently, the principles of magnetic-induction hyperthermia in magnetic nanoparticle hyperthermia are considered an effective treatment for cancer cells. As reported in previous articles, these nanoparticles generate a lot of heat that raises the temperatures of tumors, hence treating the cancer cells. The other significant potential of magnetic nanoparticles is the ability to combine heat and drug release for cancer treatment. However, within the biologically safe range of AC magnetic fields, the lack of induction heating power and the high criteria for biocompatibility in superparamagnetic-nanoparticle hyperthermia agents still make up the key challenges for the successful clinical application of magnetic hyperthermia. In this study, two different types of iron oxide nanoparticles (γ-Fe2O3, Fe3O4) were modified with whey protein isolate (WPI) to form bio-modified superparamagnetic nanoparticles with spherical or diamond-shaped structures and diameters between 20 and 100 nm, which demonstrate excellent stability under different conditions. Adriamycin (ADM) has also been successfully loaded onto these nanoparticles and used in this experiment. In vitro and in vivo experimental studies were performed using these WPI-modified nanoparticles on HepG2 tumor models and mice to assess their bioavailability and biological feasibility. The results prove that these WPI-modified nanoparticles perform satisfactorily in conjunction with hyperthermia to cure tumors completely.

Synthesis and characterization of modified magnetic nanoparticles as theranostic agents: in vitro safety assessment in healthy cells

Over the past few decades nanotechnology has paved its way into cancer treatment procedures with the use of nanoparticles (NPs) for contrast media and therapeutic agents. Iron based NPs are the most investigated since they can be used for drug delivery, imaging and when magnetically activate employed as local heat sources in cancer hyperthermia. In this work, was performed synthesis, characterization and biological evaluation of different types of iron oxide nanoparticles (mNPs'), as promising material for tumor hyperthermia. The surface of mNPs' has modified with inorganic stabilizing agents to particularly improve characteristics such as their magnetic properties, colloidal stability and biocompatibility. The successful coating of mNPs' was confirmed by morphological and structural characterization by transmission electron microscopy (TEM) and Fourier-Transform Infra-Red spectroscopy (FT-IR), while their hydrodynamic diameter was studied by using Dynamic light scattering (DLS). X-ray Diffraction (XRD) proved that the crystallite phase of mNPs' is the same with the pattern of magnetite. Superparamagnetic behavior and mNPs' response under the application of alternating magnetic field (AMF) were also thoroughly investigated and showed good heating efficiency in magnetic hyperthermia experiments. The contrast ability in magnetic resonance imaging (MRI) is also discussed indicating that mNPs are negative MRI contrast types. Nonetheless the effects of mNPs on cell viability was performed by MTT on human keratinocytes, human embryonic kidney cells, endothelial cells and by hemolytic assay on erythrocytes. In healthy keratinocytes wound healing assay in different time intervals was performed, assessing both the cell migration and wound closure. Endothelial cells have also been studied in functional activity performing capillary morphogenesis. In vitro studies showed that mNPs are safely taken by the healthy cells and do not interfere with the biological processes such as cell migration and motility.

Drought stress amelioration in plants using green synthesised iron oxide nanoparticles

Abstract With rising air pollution and global warming, the threat of impending drought in agricultural areas is a frightful scenario. Mitigation of such types of drought stress in Indian context is all the more important as Climate Change induced drought is poised to affect Indian farms in the future. The alleviation of abiotic stress in plants by employing iron oxide nanoparticles (FeNp) is a novel approach, not much reported. Hence, in the present study we undertook green synthesis of Iron oxide nanoparticles/magnetite (Fe3O4-Np) from a marine algae Chaetomorpha antennina (green algae). Henceforth, two types of Iron oxide nanoparticles were synthesized, characterized and employed further – bare FeNp and citrate coated FeNp. The biogenic iron oxide nanoparticles have been employed as a nano-fertilizer. However its active mechanism in the amelioration of drought stress is unknown. Henceforth, we wanted to establish the role of FeNp under drought stressed conditions and by coating it further with citrate we observed an enhanced stress amelioration effect. Drought stressed Setaria italica plants were treated with green synthesised iron oxide nanoparticles, both bare as well as capped. These FeNp not only serve as a nanonutrient for the plant, but also enabled the plant to overcome drought stress. An overall increase in the plant (Setaria italica) growth was detected. It was also observed that with increasing concentrations of FeNp (Fe3O4), the seedlings showed a concomitant increase in chlorophyll as well as soluble sugar content, suggesting that the iron up taken by the plants were used up for producing photoassimilates. The iron, H2O2 as well as proline content in the plants was also estimated, which further confirmed that the plants readily uptook FeNp and overcame the drought stress. Thus we could conclude from our experiments that, FeNp (both capped as well as bare FeNp) are effective in conferring the plants, ability to ameliorate drought stress. Throughout the experiment no toxic effect was observed in the plants. This confirms the potential of green synthesized FeNp, as an eco-friendly fertilizer even under drought stressed conditions.

The shuttling effects and associated mechanisms of different types of iron oxide nanoparticles for Cu(II) reduction by Geobacter sulfurreducens

Iron oxide nanoparticles (IONPs), commonly occurring in soils, aquifers and subsurface sediments, may serve as important electron shuttles for the biotransformation of coexisting toxic metals. Here, we explored the impact of different IONPs (low-crystallinity goethite and ferrihydrite, high-crystallinity magnetite and hematite) on the reduction of Cu(II) by Geobacter sulfurreducens and the associated electron shuttle mechanisms. All four IONPs tested can function as electron shuttles to enhance long distance electron transfer from bacteria to Cu(II). Upon IONPs addition, the rate of Cu(II) reduction increased from 14.9 to 65.0–83.8 % in solution after 7 days of incubation. Formation of both Cu(I) and Cu(0) on the iron oxide nanoparticles was revealed by the X-ray absorption near-edge spectroscopy. The IONPs can be utilized as conduits by bacteria to directly transfer electrons and they can also reversibly accept and donate electrons as batteries through a charging-discharging cycle to transfer electron. The latter mechanism (geo-battery) played an important role in all four types of IONPs while the former one (geo-conductor) can only be found in the magnetite and hematite treatments due to the higher crystallinity. Our results shed new light on the biogeochemically mediated electron flux in microbe-IONPs-metal networks under anaerobic iron-reduction conditions.

Synthesis method of novel Gd2O3@Fe3O4 nanocomposite modified by dextrose capping agent

In current study, gadolinium oxide was heterogeneously formed on the surface of iron oxide nanoparticles and further modified with dextrose capping agent to be used in biomedical applications, especially for contrast enhancement in MR images. First, two types of iron oxide nanoparticles were prepared at 25 and 80 °C via simple coprecipitaion method. Then, gadolinium oxide nanoparticles were synthesized through a consecutive precipitation process on previously formed iron oxide seeds in an aqueous media and subsequent annealing at 300 °C. Finally, dextrose was used as capping agent to stabilize nanocomposites in a colloidal suspension. X-ray diffraction (XRD), Scanning and Transmission electron microscopy, Dynamic Laser Scattering (DLS), Fourier-Transform Infrared Spectroscopy (FTIR), and Magnetometery (VSM) techniques were employed for nanocomposites investigation and MTT-assay method used for viability assessment of colloidal samples. Measurements based on Scherrer equation from XRD patterns showed that increasing coprecipitation temperature resulted bigger iron oxide crystallites. The iron oxide crystallite size was increased from 15.1 to 28.1 nm. Precipitation process led to gadolinium oxide formation with 30.7 and 38.8 nm crystallite sizes, respectively. TEM images revealed that iron oxide agglomerates were encapsulated in gadolinium oxide surroundings. Hydrodynamic size of the coated nanoparticles with dextrose was 208 and 247 nm. In VSM examinations, nanocomposites did not display coercive field and the saturation magnetization was 1.93 emu/g. MTT-assay results showed 80% viability in 285 μg nanocomposites containing 96.9 μg [Fe] and 11.4 μg [Gd].

Nanoscale Heat Transfer from Magnetic Nanoparticles and Ferritin in an Alternating Magnetic Field

Recent suggestions of nanoscale heat confinement on the surface of synthetic and biogenic magnetic nanoparticles during heating by radio frequency-alternating magnetic fields have generated intense interest because of the potential utility of this phenomenon for noninvasive control of biomolecular and cellular function. However, such confinement would represent a significant departure from the classical heat transfer theory. Here, we report an experimental investigation of nanoscale heat confinement on the surface of several types of iron oxide nanoparticles commonly used in biological research, using an all-optical method devoid of the potential artifacts present in previous studies. By simultaneously measuring the fluorescence of distinct thermochromic dyes attached to the particle surface or dissolved in the surrounding fluid during radio frequency magnetic stimulation, we found no measurable difference between the nanoparticle surface temperature and that of the surrounding fluid for three distinct nanoparticle types. Furthermore, the metalloprotein ferritin produced no temperature increase on the protein surface nor in the surrounding fluid. Experiments mimicking the designs of previous studies revealed potential sources of the artifacts. These findings inform the use of magnetic nanoparticle hyperthermia in engineered cellular and molecular systems.

Assessing magnetic iron oxide nanoparticle properties under different thermal treatments

Magnetic nanoparticle structures have been examined as potential carrier vehicles and substrates in a wide range of applications where they undergo mechanical, chemical, and/or thermal manipulation to allow for their modification, conjugation, and transport. For safe and effective use, it is imperative to not only measure the initial physicochemical and structural properties of nanomaterials, but also identify and quantify any property changes related to a loss of chemical and/or physical integrity during processing and usage conditions. In this study, an assessment of iron oxide magnetic nanoparticle thermal stability using modulated differential scanning calorimetry (mDSC) and a controlled heating system is conducted on two types of iron oxide nanoparticles: maghemite (Fe2O3; 500 nm) with silanol surface functional groups and magnetite (Fe3O4; 200 nm) with primary amine-terminated alkoxysilane surface functional groups. mDSC results revealed an endothermic peak at 388 K for both types of nanoparticles indicating possible molecular rearrangement within the structure. To confirm this result, iron oxide nanoparticles in aqueous suspensions were heated at discrete temperatures from 303 to 403 K. Calorimetry, FTIR spectroscopy, and dynamic light scattering measurements were used to examine changes in the chemical and physical stability of the suspensions. Morphological characteristics were evaluated using optical microscopy, transmission electron microscopy, and atomic force microscopy. Results showed that the chemical and morphological structure of the nanocomposite is critical in determining the thermal performance of the iron oxide nanoparticles. Amine-terminated silane-functionalized magnetite nanoparticles were highly susceptible to morphological and surface chemistry changes starting at ca. 353 K. Conversely, silanol-functionalized maghemite nanoparticles were shown to be stable in terms of morphology and chemical structure up to 403 K. Micrographs demonstrated variations in magnetic domains distribution after exposing the nanoparticles to thermal treatments, confirming the results obtained through mDSC and FTIR measurements.

Therapeutic efficacy of Phyllanthus emblica-coated iron oxide nanoparticles in A549 lung cancer cell line.

Aim: Present work was undertaken to fabricate iron oxide nanoparticles (IONPs) using a green approach for increased therapeutic efficacy. Materials & methods: Two types of IONPs were synthesized, one without any coating (IONPUC) and other coated with Phyllanthus emblica (Amla) fruit extract (IONPA). Both the IONPs were characterized using different techniques and therapeutic efficacy was evaluated in A549 human lung cancer cell line. Results: IONPA were smaller in size with better dispersibility compared with IONPUC. They induced increased reactive oxygen species production, higher DNA damage and apoptosis, which resulted in increased toxicity to cancer cells in comparison to IONPUC. Conclusion: Higher uptake of IONPA and active components coating the surface, may be responsible for the increased therapeutic efficacy in cancer cells.

Plasma protein adsorption on Fe3O4-PEG nanoparticles activates the complement system and induces an inflammatory response.

BackgroundUnderstanding of iron oxide nanoparticles (IONP) interaction with the body milieu is crucial to guarantee their efficiency and biocompatibility in nanomedicine. Polymer coating to IONP, with polyethyleneglycol (PEG) and polyvinylpyrrolidone (PVP), is an accepted strategy to prevent toxicity and excessive protein binding.AimThe aim of this study was to investigate the feature of IONP adsorption of complement proteins, their activation and consequent inflammatory response as a strategy to further elucidate their biocompatibility.MethodsThree types of IONP with different surface characteristics were used: bare (IONP-bare), coated with PVP (IONP-PVP) and PEG-coated (IONP-PEG). IONPs were incubated with human plasma and adsorbed proteins were identified. BALB/c mice were intravenously exposed to IONP to evaluate complement activation and proinflammatory response.ResultsProtein corona fingerprinting showed that PEG surface around IONP promoted a selective adsorption of complement recognition molecules which would be responsible for the complement system activation. Furthermore, IONP-PEG activated in vitro, the complement system and induced a substantial increment of C3a and C4a anaphylatoxins while IONP-bare and IONP-PVP did not. In vivo IONP-PEG induced an increment in complement activation markers (C5a and C5b-9), and proinflammatory cytokines (IL-1β, IL-6, TNF-α).ConclusionThe engineering of nanoparticles must incorporate the association between complement proteins and nanomedicines, which will regulate the immunostimulatory effects through a selective adsorption of plasma proteins and will enable a safer application of IONP in human therapy.