Coated Iron Oxide Nanoparticles Research Articles

Aerobic Oxidation of Alcohols and Olefins Using Ru NPs Decorated on Functionalized PNIPAM Grafted Magnetic Nanoparticles

ABSTRACTA thermo‐responsive ruthenium catalyst was produced by immobilizing poly(N‐isopropyl acrylamide) on the silica surface coated iron oxide nanoparticles (Fe3O4@Si). After being exposed to ethylenediamine, the amino‐modified support (Fe3O4@Si‐PNIPAM‐NH2) was produced, and Fe3O4@Si‐PNIPAM‐NH2‐EDTA was made in the ensuing reaction with EDTA (ethylenediaminetetraacetic acid). Ru NPs were introduced to the modified magnetic support to create a well‐organized heterogeneous catalytic system with several advantages, such as enabling catalyst recycling and simple separation. This new catalyst was characterized by means of various techniques, including TGA, ICP, FT‐IR, DLS, TEM, SEM, EDX, VSM, XRD, CHN, and XPS. In the presence of H2O2 or air alone, this catalyst showed a significant effect in the oxidation of various alcohols to the corresponding aldehydes or ketones. Furthermore, the catalyst exhibited outstanding capacity in the aerobic oxidation of olefines to the carbonyl or oxirane counterparts. A main aspect of this catalytic system is the reusability of the catalyst at least eight times in consecutive runs without causing any discernible loss of activity, structural change, or leaching.

Magnetic bio-composite based on zirconium and chitosan modified activated carbon from peanut husk with enhanced antibacterial and adsorptive potential for alizarin red and congo red in wastewater

Creating new adsorbents is crucial for removing contaminants from water due to increased industrialization, which has worsened water pollution in recent years. In this study, a magnetic biocomposite, Zirconium (Zr)-doped chitosan (CS)-coated iron oxide nanoparticles (Fe3O4-NPs)-peanut husk (PH)-based activated carbon (AC) (Zr-CS/Fe3O4-NPs@PH-AC), was synthesized for efficient removal of alizarin red (AR) and congo red (CR) dyes, alongside antibacterial applications. Characterization via scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis revealed micropores and mesopores development due to chemical activation of PH biomaterial and Fe3O4-NPs addition. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) identified functional groups and structural properties. Vibrating sample magnetometry (VSM) analyzed magnetic properties. Optimal conditions for AR/CR removal were determined, including Zr-CS/Fe3O4-NPs@PH-AC dose, dye dose, contact time, and temperature, achieving maximum removal percentages. Experimentally determined maximum adsorption capacities for AR and CR were 374.3 and 154.1 mg·g−1, respectively. Cytotoxicity studies affirmed the eco-friendly and non-toxic nature of the adsorbent by exhibiting the reduction in the cell viability from 100 % to 88.68 % from the 0 to 200 μg·L−1 respectively. Additionally, the biocomposite exhibited significant antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) due to magnetic NPs. The material in this study shows extreme compatibility for numerous applications.

Investigation of silica coated iron oxide nanoparticles and activated carbon as a potential fluid loss additive and Pakistan shale inhibitor in water-based mud system coupled with advance image processing technique

Investigation of silica coated iron oxide nanoparticles and activated carbon as a potential fluid loss additive and Pakistan shale inhibitor in water-based mud system coupled with advance image processing technique

Hyperthermia/glutathione-triggered ferritin nanoparticles amplify the ferroptosis for synergistic tumor therapy

Breast cancer is the most diagnosed malignancy in women globally, and drug resistance is among the major obstacles to effective breast cancer treatment. Emerging evidence indicates that photothermal therapy and ferroptosis are both promising therapeutic techniques for the treatment of drug-resistant breast tumors. In this study, we proposed a thermal/ferroptosis/magnetic resonance imaging (MRI) triple functional nanoparticle (I@P-ss-FRT) in which ferritin, an iron storage material with excellent cellular uptake capacity, was attached via disulfide bonds onto polydopamine coated iron oxide nanoparticle (I@P) as photothermal transduction agent and MRI probe. I@P-ss-FRT converted the near-infrared light (NIR) into localized heat which accelerated the release of ferrous ions from ferritin accomplished by glutathione reduction and subsequently induced ferroptosis. The drug-resistant cancer cell lines exhibited a more significant uptake of I@P-ss-FRT and sensitivity to PTT/ferroptosis compared with normal cancer cell lines. In vivo, I@P-ss-FRT plus NIR displayed the best tumor-killing potential with inhibitory rate of 83.46 %, along with a decline in GSH/GPX-4 content and an increase in lipid peroxides generation at tumor sites. Therefore, I@P-ss-FRT can be applied to combat drug-resistant breast cancer.

Nano-inducer of ferroptosis for targeted chemotherapy of human triple negative breast carcinoma

Triple negative breast carcinoma (TNBC) accounts for 15–20 % of all incident breast cancers (BC) and is known to be highly invasive, has fewer treatment options, and tends to have a worse prognosis. However, due to its biological heterogeneity and diverse clinical and epidemiological behaviors, TNBC lacks a tumor-specific targeted therapy. In the present work we have developed a TNBC-specific targeted nano-delivery agent comprising of a cRGD labeled magneto-liposome (T-LMD) co-encapsulated with oleic acid coated iron oxide nanoparticles (MN-OA) and doxorubicin (Dox) in the liposome bilayer and core, respectively. T-LMD was found to show enhanced uptake and induction of ferroptotic cell death in MDA-MB-231, a TNBC model cell line. Additionally, T-LMD induced ferroptosis was found to be accompanied by release of HMGB1, an immunogenic cell death marker, suggesting its immunogenicity for augmenting the activation of anti-tumor immunity in TNBC. The strategic placement of IONPs in the liposome bilayer of T-LMD facilitates the sensitization of MDA-MB-231 cells to undergo ferroptosis; predominantly via the activation of the iron/lipid metabolism pathway, as validated by use of small molecule ferroptosis inhibitor (ferrostatin-1) and iron chelator (deferoxamine). Activation of ferroptotic cell death was also corroborated by ferroptosis specific-ultrastructural alterations in the shape/size of cellular mitochondria and cell ballooning as observed by transmission electron microscopy and bright field imaging, respectively. Thus, our ferroptosis nano-inducer (T-LMD) can efficiently kill TNBC cells via enhanced LPO and ROS generation leading to membrane damage and consequent release of LDH and HMGB1, induce mitochondrial alterations and enhanced DNA double strand breaks. Altogether, our results suggest significant implications of T-LMD for treatment of TNBC.

Design, Synthesis, and Evaluation of Novel Magnetic Nanoparticles Combined with Thiophene Derivatives for the Removal of Cr(VI) from an Aqueous Solution.

Most heavy metals are harmful to human health and the environment, even at extremely low concentrations. In natural waters, they are usually found only in trace amounts. Researchers are paying great attention to nanotechnology and nanomaterials as viable solutions to the problem of water pollution. This research focuses on the synthesis of organic thiophene derivatives that can be used as grafted ligands on the surface of silica-coated iron oxide nanoparticles to remove Cr(VI) chromium ions from water. The Vilsmeier-Haack reaction allows the formation of aldehyde groups in thiophene derivatives, and the resulting products were characterized by the FT-IR, NMR, and GC-MS. Schiff base is used as a binder between organic compounds and nanoparticles by the reaction of aldehyde groups in thiophene derivatives and amine groups on the surface of coated iron oxide nanoparticles. Schiff base functionalized Fe3O4 composites (MNPs@SiO2-SB-THCA) and (MNPs@SiO2-SB-THCTA) were successfully synthesized by homogeneous and heterogeneous methods and characterized by a combination of FT-IR, transmission electron microscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The adsorption studies, kinetic modeling, adsorption isotherms, and thermodynamics of the two materials, MNPs@SiO2-SB-THCA and MNPs@SiO2-SB-THCTA, were investigated for the removal of Cr(VI) from water at room temperature and at 50 mg/L. The high adsorption capacity at pH 6 for MNPs@SiO2-SB-THCTA was 15.53 mg/g, and for MNPs@SiO2-SB-THCA, it was 14.31 mg/g.

Citrate coated iron oxide nanoparticles: Synthesis, characterization, and performance in protein adsorption

<p>Magnetic nanoparticles (MNPs) are extensively utilized in biomedicine as part of controlled drug release systems, hyperthermia, and magnetic resonance imaging. Surface modification of MNPs not only enhances their stability and biocompatibility but also increases affinity with certain molecules, allowing them to be used in protein separation and adsorption processes. This article reports the synthesis and characterization of iron oxide MNPs functionalized with citric acid (IONPs@CA) to evaluate their performance in protein adsorption. The nanoparticles were characterized using various techniques such as transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FT-IR). The percentage of lysozyme (Lyz) adsorbed by IONPs@CA was 84.9%, while the IONPs sample only adsorbed 5.9%. In silico evaluation results showed some repulsion bonds obtained in Lyz-IONPs and hydrogen bonds, carbon-hydrogen bonds, and van der Waals interactions in Lyz-IONPs@CA. These results may be novel since no previous research was found specifying this type of interaction between lysozyme and IONPs and/or IONPs@CA. The maximum adsorption efficiency obtained for the coated nanoparticles was 88.3%.</p>

Robust calix[4]arene-polyethyleneimine coated iron oxide nanoparticles for enhanced recovery of gold and platinum chloride complexes

Robust IONPs@X4C4@PEI samples designed for the efficient extraction of Au(iii) and Pt(iv) salts from synthetic solutions.

Coated Iron Oxide Nanoparticles as Asphaltene Inhibitors for Pore Plugging Control during Miscible Displacement in Microfluidic Glass Porous Media: A Pore-Level Study

Coated Iron Oxide Nanoparticles as Asphaltene Inhibitors for Pore Plugging Control during Miscible Displacement in Microfluidic Glass Porous Media: A Pore-Level Study

Dextran coated iron oxide nanoparticles loaded with protocatechuic acid as multifunctional therapeutic agents

Nowadays, there is a growing interest in multifunctional therapeutic agents as valuable tools to improve and expand the applicability field of traditional bioactive compounds. In this context, the synthesis and main characteristics of dextran-coated iron oxide nanoparticles (IONP-Dex) loaded with both an antioxidant, protocatechuic acid (PCA), and an antibiotic, ceftazidime (CAZ) or levofloxacin (LEV) are herein reported for the first time, with emphasis on the potentiation effect of PCA on drugs activity. All nanoparticles were characterized by transmission electron microscopy, X-ray diffraction, vibrating sample magnetometry, differential scanning calorimetry and dynamic light scattering. As evidenced by DPPH method, IONP-Dex loaded with PCA and LEV had similar antioxidant activity like those with PCA only, but higher than PCA and CAZ loaded ones. A synergy of action between PCA and each antibiotic co-loaded on IONP-Dex has been highlighted by an enhanced activity against reference bacterial strains, such as S. aureus and E. coli after 40 min of incubation. It was concluded that PCA, which is the main cause of the antioxidative properties of loaded nanoparticles, further improves the antimicrobial activity of IONP-Dex nanoparticles when was co-loaded with CAZ or LEV antibiotics. All constructs also showed a good biocompatibility with normal human dermal fibroblasts.

A new biosensing platform based on L-cysteine-capped Fe3O4 nanoparticles embedded in chitosan-MWCNT matrix: Electrochemical kinetic and sensing studies

We present a report on the electrochemical kinetics and sensing studies conducted on a flexible ITO-PET transducer, fabricated with a new nanocomposite of L-cysteine coated iron oxide nanoparticles (LCys@Fe3O4 NPs) and multi-wall carbon nanotubes (MWCNT), for the first time. Synthesized via the wet-chemical co-precipitation method, the LCys@Fe3O4 NPs exhibit a pure cubic phase. A nanocomposite of these LCys@Fe3O4 NPs are prepared via dispersion in chitosan (CS) solution along with MWCNT, and further drop-casted onto a low-cost, flexible ITO-PET sheet. The fabricated CS-MWCNT-LCys@Fe3O4/ITO-PET electrode shows a higher surface roughness, compared to either MWCNT or LCys@Fe3O4 modified electrode counterpart. The CS-MWCNT-LCys@Fe3O4 nanocomposite exhibits a twofold enhancement of the peak anodic voltammetric current, and a tenfold decrease in the charge transfer resistance, as compared to the LCys@Fe3O4 nanoparticles. Additionally, a mathematical model is devised to evaluate the kinetic parameters (ks, α & DFe(II)) of the redox species K4[Fe(CN)6]/K3[Fe(CN)6] on the CS-MWCNT-LCys@Fe3O4/ITO-PET surface, confirming a quasi-reversible electron transfer process. We couple this transducer with an immunosandwich format to facilitate rapid and ultrasensitive electrochemical measurement of protein biomarkers. Proof-of-concept is carried out by measuring the SARS-CoV-2 spike glycoprotein on the biofunctionalized Ab1/CS-MWCNT-LCys@Fe3O4/ITO-PET immunoelectrodes within a wide linear range (1 pg mL-1-1 μg mL-1). The immunoelectrode encompasses a limit of detection of 0.932 pg mL-1, and a sensitivity of 0.499 μA pg−1 mL cm−2. Thus, CS-MWCNT-LCys@Fe3O4 presents a new and excellent nanocomposite for biosensing application, while the Ab1/CS-MWCNT-LCys@Fe3O4/ITO-PET immunoelectrode can serve as an efficient, flexible, and cost-effective biosensing platform which can further be utilised to fabricate point-of-care biosensors.

Magnetic separation-enhanced photoluminescence detection of dipicolinic acid and quenching detection of Cu(II) ions

Dipicolinic acid (DPA) is a chelate capable of binding to a variety of lanthanide ions to make them luminescent in the visible range. Based on this property and also assisted by magnetic separation, we report a strategy for the sensitive detection of DPA. Poly(acrylic acid)-coated iron oxide nanoparticles (IONPs) serve as a magnetic carrier to deliver only a necessary amount of Tb3+ ions to DPA in a sample solution. This enables photoluminescence measurement of the Tb3+-DPA complex with minimal background noise. The obtained detection limit, which is as low as 0.236 nM, is more than two orders of magnitude lower than that of the assay not assisted by magnetic separation. Not only does this method possess a potential for diagnosing anthrax, given that DPA is a major constituent of Bacillus anthracis spores, but it is also useful for detecting aqueous Cu2+ ions through the luminescence quenching effect. High sensitivity with a detection limit of 54 nM [Cu2+] is demonstrated using the Eu3+-DPA complex.

Determination of the Size of Complex Iron Oxide Nanoparticles Using Various Physical Experimental Methods

A series of organically coated iron oxide nanoparticles obtained via the thermal decomposition of iron–oleate complexes via a “heating-up” process were investigated using the methods of transmission electron microscopy, X-ray diffraction and fine magnetometry, accompanied by elaborate mathematical analysis. The analysis of dependencies of field dependencies on the magnetization of the shape and broadening of maxima of X-ray diffraction patterns and fine refinement of transmission electron microscopy data allowed us to demonstrate that all of the samples under consideration had a tripartite structure: (i) the magnetic crystalline core of iron oxide, (ii) the paramagnetic stratum of amorphous iron oxide and (iii) the organic coater. The new approach toward synthesis for organic coated iron oxide shows that it could be applied to the preparation of magnetic nanoparticles with different and controlled magnetic properties and sizes depending on necessary applications, especially biomedical.

Probability of Cavitation in a Custom Iron-Based Coupling Medium for Transcranial Magnetic Resonance-Guided Focused Ultrasound Procedures.

A coupling bath of circulating, chilled, degassed water is essential to safe and precise acoustic transmittance during transcranial magnetic resonance-guided focused ultrasound (tMRgFUS) procedures, but the circulating water impairs the critical real-time magnetic resonance imaging (MRI). An iron-based coupling medium (IBCM) using iron oxide nanoparticles previously developed by our group increased the relaxivity of the coupling bath such that it appears to be invisible on MRI compared with degassed water. However, the nanoparticles also reduced the pressure threshold for cavitation. To address this concern for prefocal cavitation, our group recently developed an IBCM of electrosterically stabilized and aggregation-resistant poly(methacrylic acid)-coated iron oxide nanoparticles (PMAA-FeOX) with a similar capability to reduce the MR signal of degassed water. This study examines the effect of the PMAA-FeOX IBCM on the cavitation threshold. Increasing concentrations of PMAA-FeOX nanoparticles in degassed, deionized water were placed at the focus of two different transducers to assess low and high duty-cycle pulsing parameters which are representative of two modes of focused ultrasound being investigated for tMRgFUS. Passive cavitation detection and high-speed optical imaging were used to measure cavitation threshold pressures. The mean cavitation threshold was determined in both cases to be indistinguishable from the degassed water control, between 6-8 MPa for high duty-cycle pulsing (CW) and between 25.5-26.5 MPa for very low duty-cycle pulsing. The findings of this study indicate that an IBCM of PMAA-FeOX nanoparticles is a possible solution to reducing MRI interference from the coupling bath without increasing the risk of prefocal cavitation.

Chain length impact on the retro Diels-Alder mediated release of gemcitabine from hybrid nanoparticles towards pancreatic cancer therapy

Previously reported gold coated iron oxide nanoparticles (Au-IONP’s) have demonstrated their effectiveness as drug delivery vehicles for gemcitabine conjugated to a thermally labile Diels-Alder linker containing a chain of 4 carbon atoms (TTLD4) for the treatment of pancreatic cancer. Heat generated via laser irradiation of Au-IONPs facilitated retro Diels-Alder mediated release in a burst release profile where approximately half of all total release over 180 min occurred within the first 5 min. Two analogues of TTLD4, which differ only in linker chain length (TTLD3 & TTLD6) were synthesised and conjugated to Au-IONP’s. Heat-mediated release of gemcitabine at 45 °C over 180 min from these formulations was confirmed to be based on linker length, which was 94%, 76% and 45% for TTLD3, TTLD4 and TTLD6, respectively. Drug loading of the Diels-Alder linkers in a 5:1 Drug/Au-IONP w/w ratio appears to favour those containing an even number of carbons TTLD4 (76%) & TTLD6 (57%) over TTLD3 (25%), possibly due to the linker likely being positioned perpendicular to the Au-IONP surface because of the 120 °C–C bond.

Glucan Coated Iron Oxide Nanoparticles for Regulating Survival, Inflammation and Oxidative Stress in Parkinsons Disease

This study assessed the mechanism of Iron Oxide Nanoparticles (IONP) coated with glucan in regulating survival, inflammation and oxidative stress in Parkinson’s disease (PD). IONP coated with glucan (NPs) was established and identified. BV-2 cells were randomly divided into the following three sets; control set, PD set, and NPs set. Apoptotic activity of nerve cells, expression of TNF-α, IL-6 and IL-1β, and content of reactive oxygen species (ROS) and malondialdehyde (MDA) were was also analyzed. The expression of NF-κB and Inductible Nitric Oxide Synthase (iNOS) was detected with Western Blot, while content of glialcellline-derivedneurotrophicfactor (GDNF) was analyzed by Proliferation of nerve cells was prompted and apoptosis was restrained in the NPs set. The levels of TNF-α, IL-6 and IL-1β were reduced while contents of ROS and MDA were reduced. The expression of NF-κB and iNOS were restrained. The levels of inflammatory factors were reduced, while secretion of GDNF was reduced. The survival of nerve cells in the PD was prompted by NPs, while inflammation and oxidative stress were restrained.

Sulfobetaine-Phosphonate Block Copolymer Coated Iron Oxide Nanoparticles for Genomic Locus Targeting and Magnetic Micromanipulation in the Nucleus of Living Cells.

Exerting forces on biomolecules inside living cells would allow us to probe their dynamic interactions in their native environment. Magnetic iron oxide nanoparticles represent a unique tool capable of pulling on biomolecules with the application of an external magnetic field gradient; however, their use has been restricted to biomolecules accessible from the extracellular medium. Targeting intracellular biomolecules represents an additional challenge due to potential nonspecific interactions with cytoplasmic or nuclear components. We present the synthesis of sulfobetaine-phosphonate block copolymer ligands, which provide magnetic nanoparticles that are stealthy and targetable in living cells. We demonstrate, for the first time, their efficient targeting in the nucleus and their use for magnetic micromanipulation of a specific genomic locus in living cells. We believe that these stable and sensitive magnetic nanoprobes represent a promising tool to manipulate specific biomolecules in living cells and probe the mechanical properties of living matter at the molecular scale.

Application of magnetic iron oxide nanoparticles: Thrombotic activity, imaging and cytocompatibility of silica-coated and carboxymethyl dextrane-coated particles

Coated iron oxide nanoparticles (IONs) are promising candidates for various applications in nanomedicine, including imaging, magnetic hyperthermia, and drug delivery. The application of IONs in nanomedicine is influenced by factors such as biocompatibility, surface properties, agglomeration, degradation behavior, and thrombogenicity. Therefore, it is essential to investigate the effects of coating material and thickness on the behavior and performance of IONs in the human body. In this study, IONs with a carboxymethyl dextran (CMD) coating and two thicknesses of silica coating (TEOS0.98, and TEOS3.91) were screened and compared to bare iron oxide nanoparticles (BIONs). All three coated particles showed good cytocompatibility (>70%) when tested with smooth muscle cells over three days. To investigate their potential long term behavior inside the human body, the Fe2+ release and hydrodynamic diameters of silica-coated and CMD (carboxymethyl dextrane)-coated IONs were analyzed in simulated body fluids for 72 h at 37 °C. The ION@CMD showed moderate agglomeration of around 100 nm in all four simulated fluids and dissolved faster than the silica-coated particles in artificial exosomal fluid and artificial lysosomal fluid. The particles with silica coating agglomerated in all tested simulated media above 1000 nm. Increased thickness of the silica coating led to decreased degradation of particles. Additionally, CMD coating resulted in nanoparticles with the least prothrombotic activity, and the thick silica coating apparently decreased the prothrombotic properties of nanoparticles compared to BIONs and ION@TEOS0.98. For magnetic resonance applications, ION@CMD and ION@TEOS3.91 showed comparatively high relaxation rates R2 values. In magnetic particle imaging experiments ION@TEOS3.91 yielded the highest normalized signal to noise ratio values and in magnetic hyperthermia studies, ION@CMD and ION@TEOS0.98 showed similar specific loss power. These findings demonstrate the potential of coated IONs in nanomedicine and emphasize the importance of understanding the effect of coating material and thickness on their behavior and performance in the human body.

Insight into the photothermal therapeutic impacts of silica-coated iron oxide nanocomposites

Recently, near-infrared photothermal therapy combined with targeted nano-sensitizer has been used for cancer eradication as it protects the surrounding tissues. Although iron oxide nanoparticles (INPs) are efficient photo-heat conversion agents, they tend to agglomerate, restricting their utility in medical applications. We prepared silica-coated INPs (SCINPs) to overcome this obstacle. The physical properties of INPs and SCINPs were evaluated using transmission electron microscope (TEM), dynamic light scattering (DLS), vibrating sample magnetometer (VSM), atomic force microscope (AFM) and X-RAY diffraction (XRD). The polydispersity index (PDI) value was 0.21 and 0.44 for INPs and SCINPs, respectively. Zeta potential measurements showed that the prepared nanoparticles had negative net surface charges with average values of −28 ± 4.21 and −48 ± 5 mv for INPs and SCINPs, respectively. This is a pioneered study that evaluate the photothermal therapeutic effect of silica coated iron oxide nanoparticles. In addition to evaluate their photothermal therapeutic effect, as nano photothermal agents, using comet assay and oxidative stress parameters. Also, their photothermal therapeutic effect were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Photothermal assessment indicated that SCINPs could improve the photothermal therapy (PTT) because of their reproducible hyper-thermic and hypo-thermic effects with repeated treatment. Compared to INPs, SCINPs significantly improved the photothermal therapeutic behavior in treated cells by around 1.88 folds. SCINPs were more effective photothermal therapeutic agents and had considerable potential as novel therapeutic agents.

High-Dose Exposure to Polymer-Coated Iron Oxide Nanoparticles Elicits Autophagy-Dependent Ferroptosis in Susceptible Cancer Cells.

Ferroptosis, a form of iron-dependent, lipid peroxidation-driven cell death, has been extensively investigated in recent years, and several studies have suggested that the ferroptosis-inducing properties of iron-containing nanomaterials could be harnessed for cancer treatment. Here we evaluated the potential cytotoxicity of iron oxide nanoparticles, with and without cobalt functionalization (Fe2O3 and Fe2O3@Co-PEG), using an established, ferroptosis-sensitive fibrosarcoma cell line (HT1080) and a normal fibroblast cell line (BJ). In addition, we evaluated poly (ethylene glycol) (PEG)-poly(lactic-co-glycolic acid) (PLGA)-coated iron oxide nanoparticles (Fe3O4-PEG-PLGA). Our results showed that all the nanoparticles tested were essentially non-cytotoxic at concentrations up to 100 μg/mL. However, when the cells were exposed to higher concentrations (200-400 μg/mL), cell death with features of ferroptosis was observed, and this was more pronounced for the Co-functionalized nanoparticles. Furthermore, evidence was provided that the cell death triggered by the nanoparticles was autophagy-dependent. Taken together, the exposure to high concentrations of polymer-coated iron oxide nanoparticles triggers ferroptosis in susceptible human cancer cells.