Uniform Fe3O4/Gd2O3-DHCA nanocubes for dual-mode magnetic resonance imaging

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.

Shape programmable T1-T2 dual-mode MRI nanoprobes for cancer theranostics

The shape effect is an important parameter in the design of novel nanomaterials. Engineering the shape of nanomaterials is an effective strategy for optimizing their bioactive performance. Nanomaterials with a unique shape are beneficial to blood circulation, tumor targeting, cell uptake, and even improved magnetism properties. Therefore, magnetic resonance imaging (MRI) nanoprobes with different shapes have been extensively focused on in recent years. Different from other multimodal imaging techniques, dual-mode MRI can provide imaging simultaneously by a single instrument, which can avoid differences in penetration depth, and the spatial and temporal resolution of multiple imaging devices, and ensure the accurate matching of spatial and temporal imaging parameters for the precise diagnosis of early tumors. This review summarizes the latest developments of nanomaterials with various shapes for T₁-T₂ dual-mode MRI, and highlights the mechanism of how shape intelligently affects nanomaterials' longitudinal or transverse relaxation, namely sphere, hollow, core-shell, cube, cluster, flower, dumbbell, rod, sheet, and bipyramid shapes. In addition, the combination of T₁-T₂ dual-mode MRI nanoprobes and advanced therapeutic strategies, as well as possible challenges from basic research to clinical transformation, are also systematically discussed. Therefore, this review will help others quickly understand the basic information on dual-mode MRI nanoprobes and gather thought-provoking ideas to advance the subfield of cancer nanomedicine.

Hyaluronic acid mediated Fe3O4 nanocubes reversing the EMT through targeted cancer stem cell

Hepatocellular carcinoma (HCC) is one of the deadliest tumors in the world with a high rate of recurrence and metastasis. Therefore, the most pressing issue today is the development of new drugs, diagnostic and therapeutic approaches for effective cancer treatment. Cancer stem cells (CSCs) play a pivotal role in tumor recurrence, tumor resistance, and tumor metastasis, which provides a new perspective on the development of liver cancer. In the study, a high-temperature thermal breakdown approach was used to create composite magnetic nanocubes modified by polyethyleneimine (PEI) and hyaluronic acid (HA). The Fe₃O₄ nanocubes can recognize HCC stem cells via receptor-ligand binding of HA and CD44 (HA receptor). While loading a small molecule LDN193189 inhibited the expression of stemness-related genes OCT4 and Nanog. More crucially, the Fe₃O₄ nanocubes significantly suppressed HCC cell proliferation and migration by regulating the expression of epithelial-mesenchymal transition (EMT) process markers E-cadherin, Vimentin, and N-cadherin. Dual targeting using magnetic and receptor-mediated targeting improved the uptake of the drug delivery system. Our findings imply that the medication delivery method might be a potential therapeutic strategy for HCC.

The Advances and Biomedical Applications of Imageable Nanomaterials

Nanomedicine shows great potential in screening, diagnosing and treating diseases. However, given the limitations of current technology, detection of some smaller lesions and drugs’ dynamic monitoring still need to be improved. With the advancement of nanotechnology, researchers have produced various nanomaterials with imaging capabilities which have shown great potential in biomedical research. Here, we summarized the researches based on the characteristics of imageable nanomaterials, highlighted the advantages and biomedical applications of imageable nanomaterials in the diagnosis and treatment of diseases, and discussed current challenges and prospects.

Magnetic domains orientation in (Fe3O4/γ-Fe2O3) nanoparticles coated by Gadolinium-diethylenetriaminepentaacetic acid (Gd3+-DTPA)

In this work, the magnetic domains (MDs) orientation was evaluated from magnetite/maghemite nanoparticles (Fe3O4/γ-Fe2O3) NPs coated with Gadolinium (Gd3+) chelated with diethylenetriamine pentaacetate acid (Gd–DTPA). The (Fe3O4/γ–Fe2O3) superparamagnetic cores were configured by adding a DTPA organic layer and paramagnetic Gd as (Fe3O4/γ–Fe2O3)@Gd–DTPA NPs. The cores were obtained by coprecipitation and coated with additional modifications to the synthesis with Gd–DTPA. Analysis of properties showed that particles 9–12 nm, with Gd–DTPA layer thickness ∼10 nm increased their magnetisation from 62.72 to 75.82 emu/g. The result showed that the structure, particle size, composition, thickness and interface defects, as well as the anisotropy, play an important role in MDs orientation of (Fe3O4/γ–Fe2O3)@Gd–DTPA NPs. Magnetic force microscopy (MFM) analysis showed an MDs uniaxial orientation of 90° at magnetisation and disorder at zero conditions and demagnetisation. The MDs interactions showed uniaxial anisotropy defined in the direction of the magnetic field. These addressable and rotational features could be considered for potential applications to induce hydrogen proton alignment in water by longitudinal spin-lattice relaxation T 1 and transversal spin-spin relaxation T 2 as a dual contrast agent and as a theranostic trigger.

Fe2O3 Nanoparticles Doped with Gd: Phase Transformations as a Result of Thermal Annealing

The aim of this work is to study the effect of the phase composition of the synthesized Fe2O3-Gd2O3 nanoparticles on the efficiency of using magnetic hyperthermia as a basis for experiments. This class of structures is one of the most promising materials for biomedical applications and magnetic resonance imaging. In the course of the study, the dynamics of phase transformations of nanoparticles Fe2O3 → Fe2O3/GdFeO3 → GdFeO3 were established depending on the annealing temperature. It has been determined that the predominance of the GdFeO3 phase in the structure of nanoparticles leads to an increase in their size from 15 to 40 nm. However, during experiments to determine the resistance to degradation and corrosion, it was found that GdFeO3 nanoparticles have the highest corrosion resistance. During the hyperthermal tests, it was found that a change in the phase composition of nanoparticles, as well as their size, leads to an increase in the heating rate of nanoparticles, which can be further used for practical purposes.