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Nosocomial infections caused by Candida albicans pose serious challenges to healthcare systems due to their persistence on medical surfaces and resistance to conventional disinfectants. This study evaluates antifungal properties of SnO₂ doped with silver and cuprite nanoparticles and WO₃ thin films, as well as cobalt (CoFe₂O₄) and cobalt–nickel (Co_0.5Ni₀.₅Fe₂O₄) ferrite nanoparticles, activated by ultraviolet C (UVC) radiation, direct electric current (up to 100 V), and magnetic fields. SnO₂ films were synthesized by Spray Pyrolysis and WO₃ by Sputtering deposition, Ferrites nanoparticles by sol–gel, while metallic nanoparticles were synthetized via chemical reduction. Characterization consisted mainly of SEM, TEM, and XRD, and their antimicrobial activity was tested against C. albicans. WO₃ films achieved 86.2% fungal inhibition after 5 min of UVC exposure. SnO₂ films doped with nanoparticles reached 100% inhibition when combined with UVC and 100 V. Ferrite nanoparticles alone showed moderate activity (21.9%–40.4%) but exhibited strong surface adhesion to fungal cells, indicating potential for magnetically guided antifungal therapies. These results demonstrate the feasibility of using multifunctional nanomaterials for rapid, non-chemical disinfection. The materials are low-cost, scalable, and adaptable to hospital settings, making them promising candidates for reducing healthcare-associated fungal infections through advanced surface sterilization technologies. Full article

This review examines the emerging role of manganese-based nanoparticles (Mn-NPs) in detecting heavy metal pollutants in environmental matrices. Heavy metals such as cadmium, lead, zinc, and copper pose serious environmental and health concerns due to their tendency to persist in ecosystems and accumulate in living organisms. As a result, there is a growing need for reliable methods to detect and remove these pollutants. Manganese nanoparticles offer unique advantages that scientists could consider as replacing other metal nanoparticles, which may be more expensive or more toxic. The physicochemical properties of Mn-NPs—including their multiple oxidation states, magnetic susceptibility, catalytic capabilities, and semiconductor conductivity—enable the development of multi-modal sensing platforms with exceptional sensitivity and selectivity. While Mn-NPs exhibit inherently low electrical conductivity, strategies such as transition metal doping and the formation of composites with conductive materials have successfully addressed this limitation. Compared to noble metal nanoparticles (Au, Ag, Pd) and other base metal nanoparticles (Bi, Fe₃O₄), Mn-NPs demonstrate competitive performance without the drawbacks of high cost, complex synthesis, poor distribution control, or significant aggregation. Preliminary studies retrieved from the Scopus database highlight promising applications of manganese-based nanomaterials in electrochemical sensing of heavy metals, with recent developments showing detection limits in the sub-ppb range. Future research directions should focus on addressing challenges related to scalability, cost-effectiveness, and integration with existing water treatment infrastructure to accelerate the transition from laboratory findings to practical environmental applications. Full article

The article is devoted to the theoretical development of the mechanisms of molecular refrigeration, the area combining molecular magnetism and material science with promise for low-temperature physics and quantum computing, where conventional principles of refrigeration become inefficient. Given this general trend, we propose the concept of the magnetothermal effect in magnetically anisotropic complexes of 3d metal ions, caused by fast magnetic field quenching. Within this concept, the most topical case of an axially magnetically anisotropic system isolated from the environment by adiabatic envelope is analyzed. We evaluate the temperature change as a function of the initial temperature and magnetic field and also its dependence on the sign and the magnitude of the axial zero-field splitting parameter and the Debye temperature. Correlations are revealed between the sign of the magnetic anisotropy (dictated by the sign of the axial zero field splitting parameter) and the sign of the thermal effect (heating versus cooling) caused by field quenching. The temperature change is shown to be negative (cooling) in the case of complexes exhibiting easy-axis-type magnetic anisotropy, while for the case of easy-plane-type anisotropy, it proves to be positive (heating). The thermal effects are shown to have an efficient control by varying the initially applied field. These findings allow us to propose complexes exhibiting easy-axis-type magnetic anisotropy as candidates for achieving a low-temperature refrigeration effect caused by fast field quenching and also to employ the established magnetothermal correlations to the analysis of magnetic anisotropy. Full article

Background/Objectives: Gamma irradiation is a promising terminal sterilization method for nanoparticle-based biomedical systems. However, its potential effects on the physicochemical properties and biological performance of multifunctional nanomaterials must be carefully evaluated. This study aimed to assess the structural integrity, sterility, and cytocompatibility of magnetic nanoparticles (MNPs) and bioactive-glass-coated magnetic nanoparticles (MNPBGs), both based on magnetite (Fe₃O₄), after gamma irradiation. Methods: MNPs and MNPBGs were synthesized and subjected to gamma irradiation at 25 kGy, with additional doses explored in preliminary evaluations. Physicochemical characterizations were performed using XRD, TEM, SAED, and Raman spectroscopy. FTIR analyses were conducted on bioactive glass (BG) controls without magnetite. Sterility was evaluated via microbiological assays. Cytocompatibility and nitric oxide (NO) production were assessed using RAW 264.7 macrophages and Saos-2 osteosarcoma cells. Prussian blue staining was used to evaluate cellular uptake. Results: Gamma irradiation preserved the crystal structure, morphology, and size distribution of the nanoparticles. FTIR revealed only minor changes in the silicate network of BG, such as reduced intensity and slight shifting of Si-O-Si and Si-O-NBO bands, indicating limited radiation-induced structural rearrangement without affecting the material’s stability or cytocompatibility. Microbiological assays confirmed complete inhibition of microbial growth. All irradiated samples exhibited high cytocompatibility, with MNPBGs demonstrating enhanced biological responses. Notably, MNPBGs induced a more pronounced NO production in macrophages. Cellular uptake of nanoparticles by Saos-2 cells remained unaffected after irradiation. Conclusions: Gamma irradiation at 25 kGy is an effective sterilization strategy that maintains the structural and functional integrity of MNPs and MNPBGs. These findings support their safe use in sterile biomedical applications, particularly for bone-related therapies involving immunomodulation and drug delivery, with potential relevance for cancer treatment strategies such as osteosarcoma. Full article

Nanomaterials are materials in which at least one dimension in three-dimensional space is at the nanoscale. In recent years, nano-alumina has attracted much attention due to its large specific surface area and pore volume, as well as novel optical, magnetic, electronic, and catalytic properties. This review summarizes the preparation methods of nano-alumina based on the basic phases and properties of alumina materials, focusing on one-dimensional, two-dimensional, and three-dimensional nano-alumina preparation methods, which can provide some theoretical guidance for the subsequent development of efficient nano-alumina materials. Finally, the application of nano-alumina materials in catalysis is reviewed, and some suggestions are provided for improving the use of nano-alumina in the catalysis field. Full article

Maximizing hydrocarbon recovery from mature and complex reservoirs is constrained by heterogeneity, sand production, and harsh operational conditions. While polyacrylamide (PAM)-based systems are pivotal in addressing these challenges, a comprehensive synthesis of their transformative evolution and multifunctional capabilities remains overdue. This review critically analyzes advancements in PAM-based materials for enhanced oil recovery (EOR), conformance control, and sand management. We show that nanomaterial integration (e.g., magnetic NPs, nanoclays) significantly augments PAM’s rheological control, thermal and salinity stability, interfacial properties, and wettability alteration. Furthermore, the emergence of supramolecular chemistry has endowed PAM systems with unprecedented resilience, enabling self-healing and adaptive performance under extreme subsurface conditions. The review highlights a crucial paradigm shift towards integrated reservoir management, synergizing these advanced chemical designs with mechanical strategies and leveraging sophisticated monitoring and predictive analytics. Critically, innovations in sustainable and bio-inspired PAM materials offer environmentally responsible solutions with enhanced biodegradability. This synthesis provides a holistic understanding of the state of the art. Despite persistent challenges in scalability and predictability, continually re-engineered PAM systems are positioned as an indispensable and increasingly sustainable cornerstone for future hydrocarbon recovery in the complex energy landscape. Full article

We investigated the influence of gold deposition on the magnetic behavior, biocompatibility, and bioactivity of CoFe₂O₄ (MCF) nanomaterials (NMs) functionalized with sodium citrate (Cit) or glycine (Gly). The resulting multifunctional plasmonic nanostructured materials (MCF-Au-L, where L is Cit, Gly) exhibit superparamagnetic behavior with magnetic saturation of 59 emu/g, 55 emu/g, and 60 emu/g, and blocking temperatures of 259 K, 311 K, and 322 K for pristine MCF, MCF-Au-Gly, and MCF-Au-Cit, respectively. The MCF NMs exhibit a small uniform size (with a mean size of 7.1 nm) and an atomic ratio of Fe:Co (2:1). The gold nanoparticles (AuNPs) show high heterogeneity as determined by high-resolution transmission electron microscopy (HR-TEM) and energy-dispersive X-ray spectroscopy (EDX). The UV-Vis spectroscopy of the composites reveals two localized surface plasmons (LSPs) at 530 nm and 705 nm, while Fourier Transformed-Infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) confirm the presence of Cit and Gly on their surface. Subsequent biocompatibility tests confirm that MCF-Au-L NMs do not exert hemolytic activity (hemolysis < 5%). In addition, the CCK-8 viability assay tests indicate the higher sensitivity of cancerous cells (A549) to the photoactivity of MCF-Au compared to healthy Detroit 548 (D548) cell lines. We use advanced microscopy techniques, namely atomic force, fluorescence, and holotomography microscopies (AFM, FM, and HTM, respectively) to provide further insights into the nature of the observed photoactivity of MCF-Au-L NMs. In addition, in situ radiation, using a modified HTM microscope with an IR laser accessory, demonstrates the photoactivity of the MCF-Au NMs and their suitability for destroying cancerous cells through photodynamic therapy. The combined imaging capabilities demonstrate clear morphological changes, NMs internalization, and oxidative damage. Our results confirm that the fabricated multifunctional NMs exhibit high stability in aqueous solution, chemical solidity, superparamagnetic behavior, and effective IR responses, making them promising precursors for hybrid cancer therapy. Full article

Superhydrophobic magnetic nanomaterials (SHMNMs) are emerging as multifunctional platforms for efficient oil–water separation due to their combination of extreme water repellency, strong oil affinity, and external magnetic responsiveness. This review presents a comprehensive analysis of recent advances in the design, synthesis, and environmental application of SHMNMs. The theoretical foundations of superhydrophobicity and the physicochemical behavior of magnetic nanoparticles are first outlined, followed by discussion of their synergistic integration. Key fabrication techniques—such as sol–gel synthesis, electrospinning, dip-coating, laser-assisted processing, and the use of biomass-derived precursors—are critically assessed in terms of their ability to tailor surface morphology, chemical functionality, and long-term durability. The review further explores the mechanisms of oil adsorption, magnetic separation, and material reusability under realistic environmental conditions. Special attention is paid to the scalability, mechanical resilience, and environmental compatibility of SHMNMs in the context of water treatment technologies. Current limitations, including reduced efficiency in harsh media, potential environmental risks, and challenges in material regeneration, are discussed. This work provides a structured overview that could support the rational development of next-generation superhydrophobic materials tailored for sustainable and high-performance separation of oil and organic pollutants from water. Full article

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive type of pancreatic cancer. PDAC is difficult to diagnose due to a lack of symptoms in early stages, resulting in a survival rate of less than 10%. Moreover, often cancerous tissues cannot be surgically resected due to their deep abdomen location. Therefore, early detection is the essential strategy enabling effective PDAC treatment. Over the past few years, the development of nanomaterials for Magnetic Resonance Imaging (MRI) has expanded and improved imaging quality and diagnostic accuracy. Nanomaterials can be currently designed, manufactured and synthesized with other structures to provide improved diagnosis and advanced therapy. Although MRI equipped with the innovative nanomaterials became a powerful tool for the diagnosis and treatment of patients with various cancers, the detection of PDAC remains challenging. Nevertheless, recent advancements in PDAC theranostics provided progress in the detection and treatment of this challenging type of cancer. Present research in this area is focused on suitable carriers, eliminating delivery barriers, and the development of efficient anti-cancer drugs. Herein we discuss the current applications of iron oxide nanoparticles to the MRI diagnosis and treatment of pancreatic cancer. Full article

The preparation and use of iron oxide magnetic nanoparticles for water remediation is a widely investigated research field. To improve the efficacy of such nanomaterials, different synthetic processes and functionalization methods have been developed in the framework of green chemistry to exploit their magnetic properties and adsorption capacity in a sustainable way. In this work, iron oxide magnetic nanoparticles embedded in cross-linked sodium alginate beads designed to clean water from metal ions were magnetically characterized. In particular, the effect of copper adsorption on their magnetic properties was investigated. The magnetic characterization in a DC field of the beads before adsorption showed the presence of a superparamagnetic state at 300 K—a state that was also preserved after copper adsorption. The main differences in terms of magnetic properties before and after Cu²⁺ adsorption were the reduction of the magnetic signal (observed by comparing the saturation magnetization) and a different shape of the blocking temperature distribution obtained by magnetization versus temperature measurements. The evaluation of the reduction in magnetization can be important from the application perspective since it can affect the efficiency of the beads’ removal from the water medium after treatment. Full article

Tissue-engineered scaffolds, particularly composite scaffolds composed of polymers combined with ceramics, bioactive glasses, or nanomaterials, play a vital role in regenerative medicine by providing structural and biological support for tissue repair. As scaffold designs grow increasingly complex, the need for non-invasive imaging modalities capable of monitoring scaffold integration, degradation, and tissue regeneration in real-time has become critical. This review summarizes current non-invasive imaging techniques used to evaluate tissue-engineered constructs, including optical methods such as near-infrared fluorescence imaging (NIR), optical coherence tomography (OCT), and photoacoustic imaging (PAI); magnetic resonance imaging (MRI); X-ray-based approaches like computed tomography (CT); and ultrasound-based modalities. It discusses the unique advantages and limitations of each modality. Finally, the review identifies major challenges—including limited imaging depth, resolution trade-offs, and regulatory hurdles—and proposes future directions to enhance translational readiness and clinical adoption of imaging-guided tissue engineering (TE). Emerging prospects such as multimodal platforms and artificial intelligence (AI) assisted image analysis hold promise for improving precision, scalability, and clinical relevance in scaffold monitoring. Full article

Lanthanide rare earth elements possess significant promise for material applications owing to their distinctive optical and magnetic characteristics, as well as their versatile coordination capabilities. This study introduced a lanthanide-functionalized magnetic nanocellulose composite (NNC@Fe₃O₄@La(OH)₃) for effective phosphorus/nitrogen (P/N) ligand separation. The hybrid material employs the adaptable coordination geometry and strong affinity for oxygen of La³⁺ ions to show enhanced DNA-binding capacity via multi-site coordination with phosphate backbones and bases. This study utilized cellulose as a carrier, which was modified through carboxylation and amination processes employing deep eutectic solvents (DES) and polyethyleneimine. Magnetic nanoparticles and La(OH)₃ were subsequently incorporated into the cellulose via in situ growth. NNC@Fe₃O₄@La(OH)₃ showed a specific surface area of 36.2 m²·g⁻¹ and a magnetic saturation intensity of 37 emu/g, facilitating the formation of ligands with accessible La³⁺ active sites, hence creating mesoporous interfaces that allow for fast separation. NNC@Fe₃O₄@La(OH)₃ showed a significant affinity for DNA, with adsorption capacities reaching 243 mg/g, mostly due to the multistage coordination binding of La³⁺ to the phosphate groups and bases of DNA. Simultaneously, kinetic experiments indicated that the binding process adhered to a pseudo-secondary kinetic model, predominantly dependent on chemisorption. This study developed a unique rare-earth coordination-driven functional hybrid material, which is highly significant for constructing selective separation platforms for P/N-containing ligands. Full article

Background/Objectives: Magnetic nanoparticles, particularly iron oxide-based materials, such as magnetite (Fe₃O₄), have gained significant attention as contrast agents in medical imaging This study aimsto syntheze and characterize Fe₃O₄-based core–shell nanostructures, including Fe₃O₄@TiO₂ and Fe₃O₄@SiO₂, and to evaluate their potential as tunable contrast agents for diagnostic imaging. Methods: Fe₃O₄, Fe₃O₄@TiO₂, and Fe₃O₄@SiO₂ nanoparticles were synthesized via co-precipitation at varying temperatures from iron salt precursors. Fourier transform infrared spectroscopy (FTIR) was used to confirm the presence of Fe–O bonds, while X-ray diffraction (XRD) was employed to determine the crystalline phases and estimate average crystallite sizes. Morphological analysis and particle size distribution were assessed by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) and transmission electron microscopy (TEM). Magnetic properties were investigated using vibrating sample magnetometry (VSM). Results: FTIR spectra exhibited characteristic Fe–O vibrations at 543 cm⁻¹ and 555 cm⁻¹, indicating the formation of magnetite. XRD patterns confirmed a dominant cubic magnetite phase, with the presence of rutile TiO₂ and stishovite SiO₂ in the coated samples. The average crystallite sizes ranged from 24 to 95 nm. SEM and TEM analyses revealed particle sizes between 5 and 150 nm with well-defined core–shell morphologies. VSM measurements showed saturation magnetization (Ms) values ranging from 40 to 70 emu/g, depending on the synthesis temperature and shell composition. The highest Ms value was obtained for uncoated Fe₃O₄ synthesized at 94 °C. Conclusions: The synthesized Fe₃O₄-based core–shell nanomaterials exhibit desirable structural, morphological, and magnetic properties for use as contrast agents. Their tunable magnetic response and nanoscale dimensions make them promising candidates for advanced diagnostic imaging applications. Full article

The electrochemical conversion of CO₂ into high-purity Graphene NanoCarbon (GNC) materials provides a compelling path to address climate change while producing economically valuable nanomaterials. This work presents the progress and prospects of new large-scale syntheses of GNC allotropes via the C2CNT (CO₂ to Carbon Nano Technology) process. The C2CNT molten carbonate electrolysis technique enables the formation of Carbon NanoTubes (CNTs), Magnetic CNTs (MCNTs), Carbon Nano-Onions (CNOs), Carbon Nano-Scaffolds (CNSs), and Helical CNTs (HCNTs) directly from atmospheric or industrial CO₂. We discuss the morphology control enabled through variations in electrolyte composition, temperature, current density, and nucleation additives. We present results from scaled operations reaching up to 1000 tons/year CO₂ conversion and propose design approaches to reach megaton scales to support climate mitigation and GNC mass production. The products demonstrate high crystallinity, as evidenced by Raman, XRD, SEM, and TGA analyses, and offer promising applications in electronics, construction, catalysis, and medical sectors. Full article