Comprehensive magnetic resonance characteristics of carbon-encapsulated iron nanoparticles: a new frontier for the core-shell–type contrast agents

Abstract

The development of carbon-encapsulated iron nanoparticles (CEINS) is of considerable interest in many areas of cancer nanotechnology, ranging from basic tumor biology to early detection and treatment of cancer. To meet these challenges, the present study was undertaken to determine the magnetic and relaxometric performance of CEINS used as a new contrast agent for magnetic resonance imaging (MRI) in preclinical phantom models. CEIN samples were synthesized using a carbon arc discharge route, and the as-synthesized nanoparticles were purified and functionalized with surface acidic groups. The presence of various Fe-bearing metallic phases reflecting the net magnetic properties of CEINS was characterized by powder X-ray diffraction (XRD), thermogravimetry (TGA), and vibrating sample magnetometry. The morphological and surface chemistry features were characterized by electron microscopy (transmission electron microscopy [TEM] and scanning electron microscopy [SEM]), Raman spectroscopy, and Fourier transform-infrared (FT-IR) spectroscopy. The textural properties of CEINS, including porosity, surface total charge density, and zeta potentials, were also measured. The as-synthesized different CEIN samples were finally examined as a potent MRI contrast drug candidate. Magnetic resonance relaxation measurements were performed in bovine gelatin-based phantom models by using a 1.5-T MRI scanner equipped with a standard radiofrequency "birdcage" type head coil. To obtain data, T1-and T2-weighted MR images were acquired using the inversion recovery spin echo (SE) and the SE protocol with multiple time of echo (TE), respectively. Chemical characterization showed similarity in morphology and textural properties between assynthesized CEINS, purified CEINS, and CEINS functionalized with acidic groups. The as-synthesized CEINS had significantly higher Fe content and higher saturation magnetization. The analysis of the

Materiały Funkcjonalne Oparte Na Magnetycznych Nanokapsułkach Węglowych

“…Diagnostyka metodą magnetycznego rezonansu (MRI) jest szeroko badanym obszarem zastosowania MNKW. [20],[49]- [51] Korzystniejsze właściwości magnetyczne MNKW w porównaniu z właściwościami tlenków metali, w tym komercyjnie stosowanego nanometrycznego tlenku żelaza(III), umożliwiają uzyskiwanie obrazów o nawet dziesięciokrotnie większej rozdzielczości. Warto zauważyć, że zastosowanie MNKW w roli środka kontrastowego umożliwia osiąganie praktycznie tych samych rozdzielczości obrazów MRI jak w przypadku zastosowania metalu.…”

Atomic-scale investigation of the effect of surface carbon coatings on the oxidation and mechanical properties of iron nanowires

“…Oxidation of the reactive metallic materials and their alloys associated with corrosion is one of the longstanding problems in both materials science and nanotechnology. [1][2][3][4][5][6][7][8][9] Oxidation challenges their use and performance in a wide variety of chemically harsh oxidative reactive environments such as atmospheric exposure and chemical conditions. [1][2][3][4][5][6][7][8][9][10][11] The phenomenon exhibits a dramatic impact on the mechanical properties and eventually stability and reliability of the structural materials.…”

“…[1][2][3][4][5][6][7][8][9] Oxidation challenges their use and performance in a wide variety of chemically harsh oxidative reactive environments such as atmospheric exposure and chemical conditions. [1][2][3][4][5][6][7][8][9][10][11] The phenomenon exhibits a dramatic impact on the mechanical properties and eventually stability and reliability of the structural materials. Because of the high surface reactivity and especially high oxygen affinity, reactive metallic materials rapidly oxidize in reactive oxidizing environments where a thick oxide the shell layer completely, covering the free surface of reactive materials.…”

“…[1][2][3][4][12][13][14][15][16][17][18][19][20] Unfortunately, the oxidation process detrimentally affects materials properties such as corrosion, loss of functional properties, and reduction of mechanical strength, which leads to unpredictable failure in mechanical loadings and particularly leads to significant financial loss. [1][2][3][4][5][6][8][9][10][11][12][13][14][15]18,20 Fe and its alloys including their oxidized counterparts have been receiving significant interest for a broad range of potential applications in disparate fields including science, engineering, and technology as diverse as environmental remediation, magnetic imaging, catalysis, etc., due to their excellent magnetic, mechanical, physical and chemical properties. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][21][22][23]<...…”

“…[1][2][3][4][5][6][8][9][10][11][12][13][14][15]18,20 Fe and its alloys including their oxidized counterparts have been receiving significant interest for a broad range of potential applications in disparate fields including science, engineering, and technology as diverse as environmental remediation, magnetic imaging, catalysis, etc., due to their excellent magnetic, mechanical, physical and chemical properties. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][21][22][23][24][25][26][27][28] However, these materials undergo spontaneous oxidation with the formation of an oxide shell layer on their free surface when subjected to oxidizing environments such as exposure to O 2 molecules in the atmosphere. Therefore, a protective coating on the free surface is necessary to overcome this problem.…”