Formation of hydrated PEG layers on magnetic iron oxide nanoflowers shows internal magnetisation dynamics and generates high in-vivo efficacy for MRI and magnetic hyperthermia

Precise size control of superparamagnetic Fe3O4 nanoparticles for liver cancer diagnosis and magnetic hyperthermia therapy

Multifunctional superparamagnetic iron oxide nanoparticles are pivotal in bioapplications, with optimal size ranges varying by application. Exploring each size is essential to maximize functionality, as even 1-2 nm variations can significantly affect their properties. Therefore, discussing the effects of different sizes within the single-domain range of superparamagnetic ferrites is essential for understanding their performance in bioapplications. In this study, we synthesize monodisperse Fe3O4 nanoparticles with diameter ranging from 4.0 to 13.5 nm, the surface modified with PEGylated (Fe3O4-mPEG2000; FP), and systematically evaluate size-dependent biobehavior and potential application of FP nanoparticles in SNU423 cells. The results reveal that specific loss power (SLP) is directly proportional to particle size, and the larger FP nanoparticles enable higher hyperthermal ablation efficacy in vitro, leading to more effective tumor growth inhibition in vivo. Meanwhile, particles with smaller sizes (< 8.5 nm) generate negligible heat, rendering them unsuitable for hyperthermal therapy, but optimal for magnetic resonance imaging (MRI). This work demonstrates that FPs nanoparticles with diameter of 13.5 nm exhibit a significant synergistic anticancer effect of magnetic hyperthermal therapy and effective T2-weighted MRI with minimal side effects. This research presents important insights for nanoparticle design by precisely identifying the suitable size ranges for the biofunctions of Fe3O4 nanoparticles.

Impact of Magneto-Mechanical Actuation on Cell Differentiation: A Study Using Wireless, 3D-Printed Device and a Porous Ferrogel

Cells perceive external and internally generated forces of different kinds, significantly impacting their cellular biology. In the relatively nascent field of mechanobiology, the impact of such forces is studied and further utilized to broaden the knowledge of cellular developmental pathways, disease progression, tissue engineering, and developing novel regenerative strategies. However, extensive considerations of mechanotransduction pathways for biomedical applications are still broadly limited due to a lack of affordable technologies in terms of devices and simple magnetic actuatable materials. Herein, synthesizing a monophasic, macroporous, in situ-fabricated gelatin-based ferrogel is reported using polyethylene glycol (PEG) coated-iron oxide (magnetite) particles with high magnetization. Developing a 3D printed, compact, and wireless device capable of providing a wide range of magneto-mechanical actuation using magnetic field susceptible materials in a noncontact manner is reported. Using the device and ferrogel, C2C12 myoblast differentiation is studied under magnetic field actuation, and significant differences in the myogenin, a differentiation marker, expression behavior are observed. Due to careful design considerations, robust component selection, and easy availability of low-cost precursor for magnetic responsive material fabrication, the device-ferrogel combination can be easily adapted to routine biological studies, thereby helping mechanobiology to be utilized for developing exciting new biomedical strategies.

Magnetic chromatography improves colloidal and MRI attributes of magnetoliposomes enabling evaluation of the impact of size on bio-distribution in an in vivo model of pancreatic cancer

Magnetic chromatography was exploited to fractionate suspensions of magnetoliposomes (SML: lumen-free lipid-encapsulated clusters of multiple magnetic iron-oxide nanoparticles) improving their colloidal properties and relaxivity (magnetic resonance image contrast capability). Fractionation (i) removed sub-populations that do not contribute to the MRI response, and thus (ii) enabled evaluation of the size-dependence of relaxivity for the MRI-active part, which was surprisingly weak in the 55-90 nm range. MC was therefore implemented for processing multiple PEGylated SML types having average sizes ranging from 85 to 105 nm, which were then shown to have strongly size-dependent uptake in an in vivo pancreatic cancer model. Hence for applications in cancer diagnosis, selection of SML of suitable size for the biological target is more important than size-dependence of relaxivity.

Multicore iron oxide nanoparticles for magnetic hyperthermia and combination therapy against cancer cells

HYPOTHESIS

Multicore flower-like iron oxide nanoparticles (IONPs) are among the best candidates for magnetic hyperthermia applications against cancers. However, they are rarely investigated in physiological environments and their efficacy against cancer cells has been even less studied. The combination of magnetic hyperthermia, using multicore IONPs, with selected bioactive molecules should lead to an enhanced activity against cancer cells.

EXPERIMENTS

Multicore IONPs were synthesized by a seeded-growth thermal decomposition approach. Then, the cytotoxicity, cell uptake, and efficacy of the magnetic hyperthermia approach were studied with six cancer cell lines: PANC1 (pancreatic carcinoma), Mel202 (uveal melanoma), MCF7 (breast adenocarcinoma), MB231 (triple-negative breast cancer line), A549 (lung cancer), and HCT116 (colon cancer). Finally, IONPs were modified with a chemotherapeutic drug (SN38) and tumor suppressor microRNAs (miR-34a, miR-182, let-7b, and miR-137), to study their activity against cancer cells with and without combination with magnetic hyperthermia.

FINDINGS

Two types of multicore IONPs with very good heating abilities under magnetic stimulation have been prepared. Their concentration-dependent cytotoxicity and internalization have been established, showing a strong dependence on the cell line and the nanoparticle type. Magnetic hyperthermia causes significant cell death that is dramatically enhanced in combination with the bioactive molecules.

NIR and magnetism dual-response multi-core magnetic vortex nanoflowers for boosting magneto-photothermal cancer therapy

Due to the relatively low efficiency of magnetic hyperthermia and photothermal conversion, it is rather challenging for magneto-photothermal nanoagents to be used as an effective treatment during tumor hyperthermal therapy. The advancement of magnetic nanoparticles exhibiting a vortex-domain structure holds great promise as a viable strategy to enhance the application performance of conventional magnetic nanoparticles while retaining their inherent biocompatibility. Here, we report the development of Mn0.5Zn0.5Fe2O4 nanoflowers with ellipsoidal magnetic cores, and show them as effective nanoagents for magneto-photothermal synergistic therapy. Comparative studies were conducted on the heating performance of anisometric Mn0.5Zn0.5Fe2O4 (MZF) nanoparticles, including nanocubes (MZF-C), hollow spheres (MZF-HS), nanoflowers consisting of ellipsoidal magnetic cores (MZF-NFE), and nanoflowers consisting of needle-like magnetic cores (MZF-NFN). MZF-NFE exhibits an intrinsic loss parameter (ILP) of up to 15.3 N h m2 kg-1, which is better than that of commercial equivalents. Micromagnetic simulations reveal the magnetization configurations and reversal characteristics of the various MZF shapes. Additionally, all nanostructures displayed a considerable photothermal conversion efficiency rate of more than 18%. Our results demonstrated that by combining the dual exposure of MHT and PTT for hyperthermia treatments induced by MZF-NFE, BT549, MCF-7, and 4T1 cell viability can be significantly decreased by ∼95.7% in vitro.

Biocompatibility and proteomic profiling of DMSA-coated iron nanocubes in a human glioblastoma cell line

Background: Superparamagnetic iron core iron oxide shell nanocubes have previously shown superior performance in magnetic resonance imaging T2 contrast enhancement compared with spherical nanoparticles. Methods: Iron core iron oxide shell nanocubes were synthesized, stabilized with dimercaptosuccinic acid (DMSA-NC) and physicochemically characterized. MRI contrast enhancement and biocompatibility were assessed in vitro. Results: DMSA-NC showed a transverse relaxivity of 122.59 mM-1·s-1 Fe. Treatment with DMSA-NC did not induce cytotoxicity or oxidative stress in U-251 cells, and electron microscopy demonstrated DMSA-NC localization within endosomes and lysosomes in cells following internalization. Global proteomics revealed dysregulation of iron storage, transport, transcription and mRNA processing proteins. Conclusion: DMSA-NC is a promising T2 MRI contrast agent which, in this preliminary investigation, demonstrates favorable biocompatibility with an astrocyte cell model.

Biomedical Approach of Nanotechnology and Biological Risks: A Mini-Review

Nanotechnology has played a prominent role in biomedical engineering, offering innovative approaches to numerous treatments. Notable advances have been observed in the development of medical devices, contributing to the advancement of modern medicine. This article briefly discusses key applications of nanotechnology in tissue engineering, controlled drug release systems, biosensors and monitoring, and imaging and diagnosis. The particular emphasis on this theme will result in a better understanding, selection, and technical approach to nanomaterials for biomedical purposes, including biological risks, security, and biocompatibility criteria.

Transition metal compounds: From properties, applications to wettability regulation

Transition metal compounds (TMCs) have the advantages of abundant reserves, low cost, non-toxic and pollution-free, and have attracted wide attention in recent years. With the development of two-dimensional layered materials, a new two-dimensional transition metal carbonitride (MXene) has attracted extensive attention due to its excellent physicochemical properties such as gas selectivity, photocatalytic properties, electromagnetic interference shielding and photothermal properties. They are widely used in gas sensors, oil/water separation, wastewater and waste-oil treatment, cancer treatment, seawater desalination, strain sensors, medical materials and some energy storage materials. In this view, we aim to emphatically summarize MXene with their properties, applications and their wettability regulation in different applications. In addition, the properties of transition metal oxides (TMOs) and other TMCs and their wettability regulation applications are also discussed.

Emerging Magnetic Fabrication Technologies Provide Controllable Hierarchically-Structured Biomaterials and Stimulus Response for Biomedical Applications

Multifunctional nanocomposites which exhibit well-defined physical properties and encode spatiotemporally-controlled responses are emerging as components for advanced responsive systems. For biomedical applications magnetic nanocomposite materials have attracted significant attention due to their ability to respond to spatially and temporally varying magnetic fields. The current state-of-the-art in development and fabrication of magnetic hydrogels toward biomedical applications is described. There is accelerating progress in the field due to advances in manufacturing capabilities. Three categories can be identified: i) Magnetic hydrogelation, DC magnetic fields are used during solidification/gelation for aligning particles; ii) additive manufacturing of magnetic materials, 3D printing technologies are used to develop spatially-encoded magnetic properties, and more recently; iii) magnetic additive manufacturing, magnetic responses are applied during the printing process to develop increasingly complex structural arrangement that may recapitulate anisotropic tissue structure and function. The magnetic responsiveness of conventionally and additively manufactured magnetic hydrogels are described along with recent advances in soft magnetic robotics, and the categorization is related to final architecture and emergent properties. Future challenges and opportunities, including the anticipated role of combinatorial approaches in developing 4D-responsive functional materials for tackling long-standing problems in biomedicine including production of 3D-specified responsive cell scaffolds are discussed.

Iron-Based Ceramic Composite Nanomaterials for Magnetic Fluid Hyperthermia and Drug Delivery

Because of the unique physicochemical properties of magnetic iron-based nanoparticles, such as superparamagnetism, high saturation magnetization, and high effective surface area, they have been applied in biomedical fields such as diagnostic imaging, disease treatment, and biochemical separation. Iron-based nanoparticles have been used in magnetic resonance imaging (MRI) to produce clearer and more detailed images, and they have therapeutic applications in magnetic fluid hyperthermia (MFH). In recent years, researchers have used clay minerals, such as ceramic materials with iron-based nanoparticles, to construct nanocomposite materials with enhanced saturation, magnetization, and thermal effects. Owing to their unique structure and large specific surface area, iron-based nanoparticles can be homogenized by adding different proportions of ceramic minerals before and after modification to enhance saturation magnetization. In this review, we assess the potential to improve the magnetic properties of iron-based nanoparticles and in the preparation of multifunctional composite materials through their combination with ceramic materials. We demonstrate the potential of ferromagnetic enhancement and multifunctional composite materials for MRI diagnosis, drug delivery, MFH therapy, and cellular imaging applications.