Superparamagnetic Fe3O4 Nanoparticles Research Articles

Sensitive and accurate photoluminescent-multiphonon resonant Raman scattering dual-mode detection of microRNA-21 via catalytic hairpin assembly amplification and magnetic assistance.

Anovel dual-mode detection method for microRNA-21 was developed. Photoluminescent (PL) and multiphonon resonant Raman scattering (MRRS) techniques were combined by using ZnTe nanoparticles as signal probes for reliable detection. The catalytic hairpin assembly (CHA) strategy was integrated with superparamagnetic Fe3O4 nanoparticle clusters (NCs) to enhance sensitivity. A remarkable detection sensitivity was achieved, with an ultralow limit of detection (LOD) of 310 aM for PL and 460 aM for MRRS. Awide detection range spanning from 500 aM to 100 nM for PL and 500 aM to 10 nM for MRRS was demonstrated, showcasing the versatility and efficacy of the method. Comparing to current methods and our previous work, both sensitivity and detection range showed significant advancements. The consistency between the detection results of PL and MRRS modes highlights the reliability and robustness of our method, offering compelling internal validation. This work not only opens new avenues for achieving sensitive and accurate detection of miRNAs, but also shows significant promise for advancing diagnostic applications in disease management.

Use of nanoparticle concentration and magnetic fields to control the structures of superparamagnetic Fe3O4 nanoparticle Langmuir films

Use of nanoparticle concentration and magnetic fields to control the structures of superparamagnetic Fe3O4 nanoparticle Langmuir films

Enhanced functionalization of superparamagnetic Fe3O4 nanoparticles for advanced drug enrichment and separation applications

Backgroundsuperparamagnetic ferroferric oxide (Fe3O4) nanoparticles can be extensively functionalized for applications in drug enrichment and separation. Their high magnetic responsiveness and controllable surface modification enable rapid drug enrichment and separation under external magnetic fields. This study aimed to enhance the application potential of superparamagnetic Fe3O4 nanoparticles in the field of drug enrichment and separation by functionalizing these nanoparticles to improve their biocompatibility and targeting capabilities.Methodssuperparamagnetic Fe3O4 nanoparticles functionalized with dopamine were synthesized using benzyl alcohol as the solvent and iron acetylacetonate as the precursor. The dopamine-functionalized superparamagnetic iron oxide nanoparticles were used to analyze protein enrichment and separation. Characterization of the nanoparticles was conducted, including analysis of particle size distribution, Zeta potential, and fluorescence spectra using a fluorescence spectrophotometer.Resultsthe Fe3O4 nanoparticles maintained high magnetism from the original material and exhibited uniform particle size distribution and stable Zeta potential. The saturation magnetization of dopamine-functionalized superparamagnetic Fe3O4 nanoparticles showed no significant difference compared to before coating, indicating minimal influence of dopamine on the internal magnetic core of the nanoparticles. The Fe3O4 nanoparticles demonstrated good biocompatibility and stability.Conclusionfunctionalization of superparamagnetic Fe3O4 nanoparticles significantly enhances their efficiency in drug enrichment and separation processes, suggesting broad applications in the pharmaceutical industry.

A DNA machine-based magnetic resonance imaging nanoprobe for in vivo microRNA detection

In situ monitoring microRNA (miRNA) expression in vivo holds immense potential for directly visualizing the occurrence and progression of tumors. However, the significant barrier to developing a probe that can overcome the low abundance of miRNAs while providing an output signal with unlimited tissue penetration depth remains formidable. In this study, we developed a DNA machine-based magnetic resonance imaging nanoprobe (MRINP) for amplified detection of miR-21 in vivo. The MRINP was constructed with superparamagnetic Fe3O4 nanoparticles (NPs), paramagnetic Gd-DOTA complexes, and miR-21-activated DNA machines; the DNA machine was composed of hairpin DNAzyme (HD) strands serving as the DNAzyme walker and hairpin substrate (HS) strands serving as the track. Once uptake into tumor cells, the intracellular miR-21 specifically recognized and hybridized with the HD strand, restoring the activity of DNAzyme. Subsequently, the DNAzyme walker autonomously traveled on the surface of MRINP, and each step movement of the DNAzyme walker resulted in the cleavage of its substrate strands and the ensued release of the Gd-DOTA complex-labeled oligonucleotides, turning on the T1 signal of Gd-DOTA complexes for in situ imaging of miR-21 in tumor-bearing mice. This strategy would offer a promising approach for mapping tumor-specific biomarkers in vivo with unlimited penetration depth.

Discovering the potential of biomaterial-based mesoporous and magneto-luminescent nanohybrid (Nd-doped Hydroxyapatite/Fe3O4) for cancer theragnosis

Multimodality nanoplatforms play a crucial role in advancing medical interventions by integrating multiple functionalities into a single system. However, issues like intricate production processes and biocompatibility persist. Herein, a facile synthesis of a biomaterial-based mesoporous nanocarrier, HAp:Nd+SPIONs@mSiO2 is reported. The nanohybrid with ∼100 nm average size, comprised of Nd-doped hydroxyapatite (HAp:Nd) nanophosphor, Fe3O4 superparamagnetic iron oxide nanoparticles (SPIONs), and mesoporous silica, exhibiting magneto-luminescent properties. The nanohybrid showed NIR to NIR photoluminescence properties important for deep tissue imaging. The mesoporous nanohybrid was loaded with Indocyanine green (ICG), a photosensitizer and photothermal dye, as a model drug (∼6 μg/mg of nanoparticles) with a high absorption stability retaining >75 % drug until 24 h incubation in pH 6 and 7.4, respectively. Nanoparticles demonstrated dual functionality by generating heat through magnetic and photonic stimulation, as well as producing reactive oxygen species (ROS) upon excitation with 808 nm light. In vitro assays on aggressive triple-negative breast cancer cells (MDA-MB-231) showed the high biocompatibility of nanohybrid with and without ICG, while a significant toxicity was seen after irradiation of NIR light due to ROS production. Noticeably, the nanohybrids also exhibit the ability to monitor temperature changes via Nd3+ associated NIR luminescence. The nanoplatform integrates clinically relevant components like hydroxyapatite, SPIONs, mesoporous silica and ICG, highlighting its potential for translational applications. The developed nanohybrids, with combined NIR-mediated photothermal and photodynamic effects, magnetic photothermal capabilities, and NIR/MR imaging, offer promise in addressing cancer heterogeneity and improving conventional treatments with reduced side effects.

In Vitro Superparamagnetic Hyperthermia Employing Magnetite Gamma-Cyclodextrin Nanobioconjugates for Human Squamous Skin Carcinoma Therapy.

In vitro alternative therapy of human epidermoid squamous carcinoma (A431) by superparamagnetic hyperthermia (SPMHT) using Fe3O4 (magnetite) superparamagnetic nanoparticles (SPIONs) with an average diameter of 15.8 nm, bioconjugated with hydroxypropyl gamma-cyclodextrins (HP-γ-CDs) by means of polyacrylic acid (PAA) biopolymer, is presented in this paper. The therapy was carried out at a temperature of 43 °C for 30 min using the concentrations of Fe3O4 ferrimagnetic nanoparticles from nanobioconjugates of 1, 5, and 10 mg/mL nanoparticles in cell suspension, which were previously found by us to be non-toxic for healthy cells (cell viabilities close to 100%), according to ISO standards (cell viability must be greater than 70%). The temperature for the in vitro therapy was obtained by the safe application (without exceeding the biological limit and cellular damage) of an alternating magnetic field with a frequency of 312.4 kHz and amplitudes of 168, 208, and 370 G, depending on the concentration of the magnetic nanoparticles. The optimal concentration of magnetic nanoparticles in suspension was found experimentally. The results obtained after the treatment show its high effectiveness in destroying the A431 tumor cells, up to 83%, with the possibility of increasing even more, which demonstrates the viability of the SPMHT method with Fe3O4-PAA-(HP-γ-CDs) nanobioconjugates for human squamous cancer therapy.

Superparamagnetic Fe3O4 nanoparticles capped with silver induce apoptosis of colon cancer cells via damaging DNA@increasing ROS

A sol-gel approach was used to create magnetite nanoparticles (Fe3O4 NPs) as a core and silver (Ag) as a shell. Ag-Fe3O4 NPs were identified by x-ray diffraction (XRD) and energy dispersive x-ray (EDX), scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, and vibrating sample magnetometer (VSM) techniques. The capabilities of Ag-Fe3O4 NPs to induce apoptosis were investigated utilizing the Acridine orange/Ethidium bromide stain. The activity of NPs against (HT-29) cancer cells was further evaluated in and out of the existence of near-infrared (NIR) laser beam and alternating magnetic field (AMF). The exposed laser enhanced the cytotoxicity effect against (HT-29) cells. However, greatly elevated cytotoxic activity was seen with using the AMF.

Green Synthesis of Pure Superparamagnetic Fe3O4 Nanoparticles Using Shewanella sp. in a Non-Growth Medium

Conventional wet chemical methods for the synthesis of superparamagnetic magnetite nanoparticles (MNPs) are energy-intensive and environmentally unsustainable. Green synthesis using bacteria is a less-explored approach to MNP production. Large-scale biosynthesis of MNPs has heretofore been conducted using extremophilic bacteria that exhibit low growth rates and/or require strict temperature control. However, a decrease in material and energy costs would make such bioprocesses more sustainable. In this study, Shewanella putrefaciens CN-32, an iron-reducing bacterium, was employed to reduce amorphous iron oxyhydroxide and synthesize MNPs in a non-growth medium at ambient temperature and pressure. The synthesis was conducted using plain saline solution (0.85% NaCl) to avoid impurities in the products. X-ray diffraction and transmission electron microscopy indicated that the reduction products were MNPs with a pseudo-spherical shape and 6 ± 2 nm average size. Magnetometry showed that the particles were superparamagnetic with maximum saturation magnetization of 73.8 emu/g, which is comparable to that obtained via chemical synthesis methods. Using less than a quarter of the raw materials employed in a typical chemical co-precipitation method, we obtained a maximum yield of 3.473 g/L (>5-fold increase). These findings demonstrate that our simple and ecofriendly process can help overcome the current barriers for large-scale synthesis of high-purity magnetic nanopowders.

The immobilization of L-Valine on superparamagnetic Fe3O4 nanoparticles as a novel, recoverable and green nanocatalyst for the synthesis of new thiazole derivatives

The novel immobilization of L-Valine on superparamagnetic Fe3O4 nanoparticles was prepared using a simple protocol for the first time. This compound acts as a highly efficient and recyclable heterogeneous nanocatalyst for the synthesis of thiazole derivatives via a one-pot and multi-component condensation reaction of arylglyoxals monohydrate, cyclic 1,3-dicarbonyls, and thiobenzamides in a water solvent. The structure of the nanocatalyst was characterized and confirmed using various techniques, such as Fourier transform infrared spectroscopy (FT-IR), Energy Dispersive X-ray (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TG/DTA), and vibrating sample magnetometry (VSM). This heterogeneous nanocatalyst can be easily recovered from the reaction mixture by an external magnetic field and reused for subsequent reactions at least five times without losing significant catalytic activity.

Using chitosan-coated magnetite nanoparticles as a drug carrier for opioid delivery against breast cancer

Over the past decades, opium derivatives have been discovered as new anticancer agents. In our study, Fe3O4 superparamagnetic nanoparticles (SPIONs) decorated with chitosan were loaded with papaverine or noscapine to surmount drug delivery-related obstacles. Modifying the magnetic nanoparticles (MNP) surface with polymeric materials such as chitosan prevents oxidation and provides a site for drug linkage, which renders them a great drug carrier. The obtained systems were characterized by DLS (20–40 nm were achieved for MNPs and drug- loaded MNPs), TEM (spherical with average size of 11–20 nm) FTIR, XRD, and VSM (71.3 − 42.8 emu/g). Contrary to noscapine, papaverine-MNPs attenuated 4T1 murine breast cancer cell proliferation (11.50 ± 1.74 µg/mL) effectively compared to the free drug (62.35 ± 2.88 µg/mL) while sparing L-929 fibroblast cells (138.14 ± 4.38 µg/mL). Furthermore, SPION and SPION-chitosan displayed no cytotoxic activity. Colony-formation assay confirmed the long-term cytotoxicity of nanostructures. Both developed formulations promoted ROS production accompanied by late apoptotic cell death. The biocompatible nanoparticle exerted an augmenting effect to deliver papaverine to metastatic breast cancer cells.

Purification, Characterization, and Assessment of Anticancer Activity of Iron Oxide Nanoparticles Biosynthesized by Novel Thermophilic Bacillus tequilensis ASFS1‏.

Magnetic nanoparticles (MNPs), particularly iron oxide nanoparticles (IONPs), are a fascinating group of nanoparticles that have been considerably investigated for biomedical applications because of their superparamagnetic properties, biodegradable nature, and biocompatibility. A novel Gram-positive moderately thermophilic bacterial strain, namely Bacillus tequilensis ASFS.1, was isolated and identified. This strain is capable of producing superparamagnetic Fe3O4 nanoparticles and exhibiting magnetotaxis behavior. This strain swimming behavior was investigated under static and dynamic environments, where it behaved very much similar to the magnetotaxis in magnetotactic bacteria. This study is the first report of a bacterium from the Bacillaceae family that has the potential to intracellular biosynthesis of IONPs. MNPs were separated by a magnetic and reproducible method which was designed for the first time for this study. In addition, UV-visible spectrophotometer, Fourier-transform infrared spectroscopy, vibrating sample magnetometer, field emission scanning electron microscopy (FESEM), X-ray diffraction, and thermal gravimetric analysis were utilized to characterize the bio-fabricated magnetite nanoparticles. Analysis of the particle size distribution pattern of the biogenic MNPs by FESEM imaging revealed the size range of 10-100 nm with the size range of 10-40 nm MNPs being the most frequent particles. VSM analysis demonstrated that biogenic MNPs displayed superparamagnetic properties with a high saturation magnetization value of 184 emu/g. After 24 h treatment of 3T3, U87, A549, MCF-7, and HT-29 cell lines with the biogenic MNPs, IC50 values were measured to be 339, 641, 582, 149, and 184 μg mL-1, respectively. This study presents the novel strain ASFS.1 capable of magnetotaxis by the aid of its magnetite nanoparticles and paving information on isolation, characterization, and in vitro cytotoxicity of its MNPs. The MNPs showed promising potential for biomedical applications, obviously subject to additional studies.

GMI-based biosensor for the detection and quantification of doxorubicin anticancer drugs labeled to Fe3O4 superparamagnetic nanoparticles

We present the results of research on a Co-based giant magnetoimpedance (GMI) biosensor for Fe3O4-labelled doxorubicin (DOX) anticancer drugs. Co62Fe5Ni4Si15B14 ribbons were used as biosensing material for test solutions containing different concentrations of DOX. The plain ribbon, ribbon+Fe3O4 and ribbon+DOX2 samples exhibited low coercivity (Hc), high saturation magnetization (Ms) and low anisotropy (Hk). The GMI ratio (ΔZ/Z) increased from 33% to 38% with the increase of doxorubicin content in the ribbon. It was found that the ΔZ/Z ratio first increased rapidly up to a frequency of ∼2 MHz, and then decreased slowly as the frequency increased. While the magnetic field dependent ΔZ/Z has a single peak at 1 MHz, it has a double peak at 5 MHz. It was found that the peak height of ΔZ/Z in the ribbons with test solution of 20 ng/ml and 50 ng/ml increased by ∼3% and ∼6%, respectively, compared to the ribbon without test solution. Then the ΔZ/Z ratio decreased very rapidly with the increase of the applied external magnetic fields. The frequency-dependent GMI sensitivity (η) increased with increasing frequency and reached a maximum value at a critical frequency (∼1.6 MHz), after which it decreased. The detection sensitivity of the GMI biosensor (ξ) increased rapidly with increasing doxorubicin concentration up to ∼80 ng/ml and then remained almost unchanged. The results show that doxorubicin (DOX+Fe3O4), used as an anticancer drug, can be effectively detected even at low concentrations using the GMI based sensors fabricated in this study.

Minimally Invasive Delivery of Percutaneous Ablation Agent via Magnetic Colloidal Hydrogel Injection for Treatment of Hepatocellular Carcinoma.

Percutaneous thermotherapy, a minimally invasive operational procedure, is employed in the ablation of deep tumor lesions by means of target-delivering heat. Conventional thermal ablation methods, such as radiofrequency or microwave ablation, to a certain extent, are subjected to extended ablation time as well as biosafety risks of unwanted overheating. Given its effectiveness and safety, percutaneous thermotherapy gains a fresh perspective, thanks to magnetic hyperthermia. In this respect, an injectable- and magnetic-hydrogel-construct-based thermal ablation agent is likely to be a candidate for the aforementioned clinical translation. Adopting a simple and environment-friendly strategy, a magnetic colloidal hydrogel injection is introduced by a binary system comprising super-paramagnetic Fe3O4 nanoparticles and gelatin nanoparticles. The colloidal hydrogel constructs, unlike conventional bulk hydrogel, can be easily extruded through a percutaneous needle and then self-heal in a reversible manner owing to the unique electrostatic cross-linking. The introduction of magnetic building blocks is exhibited with a rapid magnetothermal response to an alternating magnetic field. Such hydrogel injection is capable of generating heat without limitation of deep penetration. The materials achieve outstanding therapeutic results in mouse and rabbit models. These findings constitute a new class of locoregional interventional thermal therapies with minimal collateral damages.

EphA2-specific microvesicles derived from tumor cells facilitate the targeted delivery of chemotherapeutic drugs for osteosarcoma therapy

Despite advances in surgery and chemotherapy, the survival of patients with osteosarcoma (OS) has not been fundamentally improved over the last two decades. Microvesicles (MVs) have a high cargo-loading capacity and are emerging as a promising drug delivery nanoplatform. The aim of this study was to develop MVs as specifically designed vehicles to enable OS-specific targeting and efficient treatment of OS. Herein, we designed and constructed a nanoplatform (YSA-SPION-MV/MTX) consisting of methotrexate (MTX)-loaded MVs coated with surface-carboxyl Fe3O4 superparamagnetic nanoparticles (SPIONs) conjugated with ephrin alpha 2 (EphA2)-targeted peptides (YSAYPDSVPMMS, YSA). YSA-SPION-MV/MTX showed an effective targeting effect on OS cells, which was depended on the binding of the YSA peptide to EphA2. In the orthotopic OS mouse model, YSA-SPION-MV/MTX effectively delivered drugs to tumor sites with specific targeting, resulting in superior anti-tumor activity compared to MTX or MV/MTX. And YSA-SPION-MV/MTX also reduced the side effects of high-dose MTX. Taken together, this strategy opens up a new avenue for OS therapy. And we expect this MV-based therapy to serve as a promising platform for the next generation of precision cancer nanomedicines.Graphical

A nudge over the relaxation plateau: effect of pH, particle concentration, and medium viscosity on the AC induction heating efficiency of biocompatible chitosan-coated Fe3O4 nanoparticles

The effects of pH, MNP concentration, and medium viscosity on the magnetic fluid hyperthermia (MFH) properties of chitosan-coated superparamagnetic Fe3O4 nanoparticles (MNPs) are probed here. Due to the protonation of the amide groups, the MNPs are colloidally stable at lower pH (∼2), but form aggregates at higher pH (∼8). The increased aggregate size at higher pH causes the Brownian relaxation time (τ B) to increase, leading to a decrease in specific absorption rate (SAR). For colloidal conditions ensuring Brownian-dominated relaxation dynamics, an increase in MNP concentrations or medium viscosity is found to increase the τ B. SAR decreases with increasing MNP concentration, whereas it exhibits a non-monotonic variation with increasing medium viscosity. Dynamic hysteresis loop-based calculations are found to be in agreement with the experimental results. The findings provide a greater understanding of the variation of SAR with the colloidal properties and show the importance of relaxation dynamics on MFH efficiency, where variations in the frequency-relaxation time product across the relaxation plateau cause significant variations in SAR. Further, the in vitro cytotoxicity studies show good bio-compatibility of the chitosan-coated Fe3O4 MNPs. Higher SAR at acidic pH for bio-medically acceptable field parameters makes the bio-compatible chitosan-coated Fe3O4 MNPs suitable for MFH applications.

Magnetic lanthanide sensor with self-ratiometric time-resolved luminescence for accurate detection of epithelial cancerous exosomes.

Fluorescence-based LB (liquid biopsy) offers a rapid means of detecting cancer non-invasively. However, the widespread issue of sample loss during purification steps will diminish the accuracy of detection results. Therefore, in this study, we introduce a magnetic lanthanide sensor (MLS) designed for sensitive detection of the characteristic protein, epithelial cell adhesion molecule (EpCAM), on epithelial tumor exosomes. By leveraging the inherent multi-peak emission and time-resolved properties of the sole-component lanthanide element, combined with the self-ratiometric strategy, MLS can overcome limitations imposed by manual operation and/or sample complexity, thereby providing more stable and reliable output results. Specifically, terbium-doped NaYF4 nanoparticles (NaYF4:Tb) and deformable aptamers terminated with BHQ1 were sequentially introduced onto superparamagnetic silica-decorated Fe3O4 nanoparticles. Prior to target binding, emission from NaYF4:Tb at 543 nm was partially quenched due to the fluorescence resonance energy transfer (FRET) from NaYF4:Tb to BHQ1. Upon target binding, changes in the secondary structure of aptamers led to the fluorescence intensity increasing since the deconfinement of distance-dependent FRET effect. The characteristic emission of NaYF4:Tb at 543 nm was then utilized as the detection signal (I1), while the less changed emission at 583 nm served as the reference signal (I2), further reporting the self-ratiometric values of I1 and I2 (I1/I2) to illustrate the epithelial cancerous features of exosomes while ignoring possible sample loss. Consequently, over a wide range of exosome concentrations (2.28 × 102-2.28 × 108 particles per mL), the I1/I2 ratio exhibited a linear increase with exosome concentration [Y(I1/I2) = 0.166 lg (Nexosomes) + 3.0269, R2 = 0.9915], achieving a theoretical detection limit as low as 24 particles per mL. Additionally, MLS effectively distinguished epithelial cancer samples from healthy samples, showcasing significant potential for clinical diagnosis.

Precise air oxidation for continuous production of superparamagnetic Fe3O4 nanoparticles at room temperature through a microfilm reactor.

Superparamagnetic iron oxide nanoparticles (SPIONs) find vast applications in biomedicine such as drug delivery, magnetic resonance imaging (MRI) contrast agents, cell separation, tissue repair, etc. The synthesis of pure and uniform SPIONs involves tedious processes, complex precursors, the assistance of organic solvents, capping agents and/or high temperature. Herein, we report a continuous mass production of pure and uniform SPIONs in aqueous microfilm at room temperature without using any surfactant. The air oxidation rate and nanocrystal formation kinetics were precisely controlled by process intensification in the continuously flowing microfilm. Precise oxidation of Fe(ii) is a synergy of disc spinning speed and feeding concentration. The production process was continuous and conducted at room temperature in an aqueous medium with a high yield of 55.4 g h-1. The obtained products were proved to be highly pure through XRD and a colorimetric method. The resulting SPIONs exhibited a narrow size distribution, ranging from 6.5 to 12.6 nm. All sizes of the produced nanoparticles showed characteristic superparamagnetism, with the 12.6 nm SPIONs exhibiting the highest magnetization saturation (M s) of 87 emu g-1.

Superparamagnetic Artificial Cells PLGA-Fe3O4 Micro/Nanocapsules for Cancer Targeted Delivery.

Artificial cells have been extensively used in many fields, such as nanomedicine, biotherapy, blood substitutes, drug delivery, enzyme/gene therapy, cancer therapy, and the COVID-19 vaccine. The unique properties of superparamagnetic Fe3O4 nanoparticles have contributed to increased interest in using superparamagnetic artificial cells (PLGA-Fe3O4 micro/nanocapsules) for targeted therapy. In this review, the preparation methods of Fe3O4 NPs and superparamagnetic artificial cell PLGA-drug-Fe3O4 micro/nanocapsules are discussed. This review also focuses on the recent progress of superparamagnetic PLGA-drug-Fe3O4 micro/nanocapsules as targeted therapeutics. We shall concentrate on the use of superparamagnetic artificial cells in the form of PLGA-drug-Fe3O4 nanocapsules for magnetic hyperthermia/photothermal therapy and cancer therapies, including lung breast cancer and glioblastoma.

The Effect of Superparamagnetic Fe3O4 Nanoparticles Combined with Quercetin on Breast Cancer Cell Line (MCF-7)

Background: Magnetic nanoparticles attract increasing interest due to their use in cancer therapy and as drug carriers for several other diseases. The present study investigates the physiochemical properties of quercetin-conjugated superparamagnetic Fe3O4 nanoparticles and their effects on breast cancer cell line MCF-7. Methods: A simple precipitation method was used to prepare the Poly Ethylene Imine (PEI)-coated Fe3O4 nanoparticles; they were then conjugated with flavonoid-compound quercetin on the surface via carboxylic/amine group using nanoprecipitation method. Then, the physical and chemical parameters were calculated using Zeta-sizer, scanning electron microscopy (SEM), and extract release patterns at 37 and 42 0C. Finally, the toxicity level of this quercetin- conjugated nanosystem on the MCF-7 cells was investigated by MTT assay. Results: The results showed that the prepared nanosystem attained about 74% of quercetin inclusion, 91.2 nm size, 65.1 mV zeta potential, spherical morphology and a controlled release. Compared to Fe3O4 nanoparticles and pure quercetin, MTT and microscopy analysis revealed that quercetin-conjugated Fe3O4 nanoparticles induced considerable cytotoxicity, and morphology changes against MCF7 cells. Conclusion: Quercetin-conjugated Fe3O4 nanoparticles have appropriate physiochemical properties; they can be a suitable carrier for drug delivery and a promising therapy for candidates.

Tailored synthesis of iron oxide nanoparticles for specific applications using a statistical experimental design

For this work, iron oxide nanoparticles are synthesized by the co-precipitation method with stoichiometric amounts of Fe2+ and Fe3+ salts in a 1:2 ratio in distilled water and the pH is raised by adding an aqueous ammonia solution by controlled dripping. Nanoparticles precipitating after the reaction time are magnetically filtered and stored in ethanol for further analysis. Superparamagnetic Fe3O4 nanoparticles with a slight deviation from the stoichiometry are obtained, with sizes between 7.4 and 12.8 nm and saturation magnetization between 40 and 78 emu/gr. At pH 6, rod-shaped nanoparticles are obtained in addition to spherical ones. With a statistical design, it is shown how the morphological, structural and magnetic properties of the resulting nanoparticles can be manipulated by the synthesis parameters, offering many possibilities to tailor the materials to a wide range of applications.