Chemical co-precipitation from ferrous and ferric salts at a 1:1.9 stoichiometric ratio in NH₄OH base with ultrasonication (sonolysis) in a low vacuum environment has been used for obtaining colloidal suspensions of Fe₃O₄ nanoparticles coated with citric acid. Before coating, the nanoparticles were processed by electrohydraulic discharges with a high discharge current (several tens of amperes) in a water medium using a pulsed direct current. Magnetite nanoparticles were obtained with an average crystallite diameter D = 25–28 nm as obtained by XRD and particle sizes of 25 nm as measured by small-angle X-ray scattering. Magnetometry showed that all samples were superparamagnetic. The saturation magnetization for the citric acid covered samples after electrohydraulic processing showed higher value (58 emu/g) than for the directly coated samples (50 emu/g). Ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy showed the presence and binding of citric acid to the magnetite surface by chemisorption of carboxylate ions. Hydrodynamic sizes obtained from DLS and zeta potentials were 93 and 115 nm, −26 and −32 mV for the citric acid covered nanoparticles and 226 nm and 21 mV for the bare nanoparticles, respectively. The hydraulic discharge treatment resulted in a higher citric acid coverage and better particle dispersion. The developed method can be used in nanoparticle synthesis for biomedical applications.

In this study, we investigated the cytotoxicity of doxorubicin (DOX)-loaded magnetic nanofluids on 4T1 mouse tumor epithelial cells and MDA-MB-468 human triple-negative breast cancer (TNBC) cells. Superparamagnetic iron oxide nanoparticles were synthesized using sonochemical coprecipitation by applying electrohydraulic discharge treatment (EHD) in an automated chemical reactor, modified with citric acid and loaded with DOX. The resulting magnetic nanofluids exhibited strong magnetic properties and maintained sedimentation stability in physiological pH conditions. The obtained samples were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy, UV-spectrophotometry, dynamic light scattering (DLS), electrophoretic light scattering (ELS), vibrating sample magnetometry (VSM), and transmission electron microscopy (TEM). In vitro studies using the MTT method revealed a synergistic effect of the DOX-loaded citric-acid-modified magnetic nanoparticles on the inhibition of cancer cell growth and proliferation compared to treatment with pure DOX. The combination of the drug and magnetic nanosystem showed promising potential for targeted drug delivery, with the possibility of optimizing the dosage to reduce side-effects and enhance the cytotoxic effect on cancer cells. The nanoparticles’ cytotoxic effects were attributed to the generation of reactive oxygen species and the enhancement of DOX-induced apoptosis. The findings suggest a novel approach for enhancing the therapeutic efficacy of anticancer drugs and reducing their associated side-effects. Overall, the results demonstrate the potential of DOX-loaded citric-acid-modified magnetic nanoparticles as a promising strategy in tumor therapy, and provide insights into their synergistic effects.

The very high capture cross-section of (epi)thermal neutrons by the boron isotope ¹⁰B makes elemental boron and its compounds and composites prospective for serving as materials intensively interacting with neutron irradiation. In their nanostructured form, boron-rich materials reveal properties that improve their radiation-performance characteristics. In this regard, new technologies have been proposed for the synthesis of nanocomposites with matrices of boron carbide B₄C and hexagonal boron nitride h-BN. For the first time, boron carbide-tungsten and hexagonal boron nitride–(iron,magnetite) composites were obtained, respectively, in the form of layered/sandwich structures of components B₄C and W and h-BN nanopowders coated/intercalated with magnetic nanoclusters of iron Fe or magnetite Fe₃O₄. Studying of their chemical/phase composition, structure/morphology, and some other properties leads to the conclusion that the developed B₄C–W and h-BN–(Fe,Fe₃O₄) composites would be useful for solving important problems of boron-based neutron shielding and BNCT (Boron Neutron Capture Therapy), such as attenuating the gamma-radiation accompanying the absorption of neutrons by ¹⁰B nuclei and targeted delivery of ¹⁰B nuclei, as BNCT therapeutic agents, to tumor tissues using control by an external magnetic field, respectively.

The rapid progress in nanotechnology has introduced multifunctional iron oxide nanoparticles as promising agents in cancer treatment. This research focused on the synthesis and assessment of citric-acid-coated, folic-acid-conjugated nanoparticles loaded with doxorubicin, evaluating their therapeutic potential in tumor models. An advanced automated continuous technology line (CTL) utilizing a controlled co-precipitation method was employed to produce highly dispersive, multifunctional nanofluids with a narrow size distribution. Various techniques, including dynamic light scattering (DLS), electrophoretic light scattering (ELS), X-ray diffraction (XRD), and transmission electron microscopy (TEM), were employed to examine the particle size, zeta potential, structure, and morphology. Magnetic properties were analyzed through vibrating sample magnetometry (VSM), and surface modifications were confirmed via UV-visible (UV-Vis) and Fourier-Transform Infrared (FTIR) spectroscopy. Cytotoxicity and drug delivery efficiency were evaluated in vitro using RM1 (prostate cancer) and MEC1 (chronic lymphocytic leukemia) cell lines. Fluorescence microscopy demonstrated the successful intracellular delivery of doxorubicin, showcasing the nanoparticles’ potential for targeted cancer therapy. However, folic-acid-conjugated nanoparticles exhibited diminished effectiveness over time. This study highlights the importance of nanoparticle optimization for enhancing therapeutic performance. Further research should aim to improve nanoparticle formulations and explore their long-term impacts for the development of safe, targeted cancer treatments.

Recent advancements in nanotechnology have led to the development of multifunctional iron oxide nanoparticles, presenting new opportunities in cancer therapy. This study aimed to synthesize and evaluate citric acid-coated/ folic acid conjugated nanoparticles loaded with doxorubi-cin and investigate their efficacy in experimental tumor models. For synthesis, controlled co-precipitation method was employed to produce highly dispersive, multifunctional nanofluids with a narrow size distribution of iron oxide nanoparticles. Nanoparticles were characterized using Dynamic Light Scattering (DLS) and Electrophoretic Light Scattering (ELS) for size distribution and zeta potential, X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) for structure and morphology, Vibrating Sample Magnetometry (VSM) for magnetic properties, and UV-Visible (UV-Vis) and Fourier-Transform Infra-red (FTIR) spectroscopy for modification confirmation. In vitro experiments employed RM1 (prostate cancer) and MEC1 (Chronic lymphocytic leukemia) cell lines to assess cytotoxicity and drug delivery efficiency. Fluorescence microscopy confirmed the intracellular delivery of doxorubicin by these nanoparticles, highlighting their potential for targeted therapy. As a result, nanoparticles conjugated with folic acid showed reduced efficacy over time. This study underscores the critical role of nanoparticle modifications in optimizing therapeutic outcomes. Future research should focus on further refining nanoparticle formulations and long-term effects in vivo, for development of effective and safe agents for targeted cancer treatment.

Graphene oxide (GO) and reduced graphene oxide (rGO) were obtained from graphite foil wastes (GFWs) by oxidation with KMnO ₄ in the presence of concentrated sulfuric acid at 25–50°C. The resulting GOs were compared with that obtained from flake graphite under the same conditions. The samples were investigated by UV–Vis, FTIR, and Raman spectroscopy methods. Spectroscopic data, as well as EDS and XRD analyses, have shown that the GO samples obtained in both cases are almost identical. The hydrodynamic diameter and ζ-potential of both sample suspensions were also determined. The average particles size of GO(graflex) is 321.5 nm, while the particles size of GO(graphite) reaches 252 nm. The measured ζ-potential values for GO(graflex) and GO(graphite) are –31.58 and –50.04 mV, respectively. Therefore, GFWs can serve as precursor for the production of GOs.