T₁- and T₂-weighted Magnetic Resonance Dual Contrast by Single Core Truncated Cubic Iron Oxide Nanoparticles with Abrupt Cellular Internalization and Immune Evasion

Abstract

Conventional T1- or T2-weighted single mode contrast-enhanced magnetic resonance imaging (MRI) may produce false results. Thereby, there is a need to develop dual contrast agents, T1- and T2-weighted, for more accurate MRI imaging. The dual contrast agents should possess high magnetic resonance (MR) relaxivities, targeted tumor linking, and minimum recognition by the immune system. We have developed nitrodopamine-PEG grafted single core truncated cubic iron oxide nanoparticles (ND-PEG-tNCIOs) capable of producing marked dual contrasts in MRI with enhanced longitudinal and transverse relaxivities of 32 ± 1.29 and 791 ± 38.39 mM–1 s–1, respectively. Furthermore, the ND-PEG-tNCIOs show excellent colloidal stability in physiological buffers and higher cellular internalization in cancerous cells than in phagocytic cells, indicating the immune evasive capability of the nanoparticles. These findings indicate that tNCIOs are strong candidates for dual contrast MRI imaging, which is vital for noninvasive real-time detection of nascent cancer cells in vivo and for monitoring stem cells transplants.

The Effect of Surface Coating of Iron Oxide Nanoparticles on Magnetic Resonance Imaging Relaxivity

“…When IONPs are smaller than d c 10 nm, they show dual T 1 /T 2 imaging, in which T 1 enhancement refers to surface effects on the magnetization and water/ion metal center interaction on the surface of NPs (Bao et al, 2018;Thapa et al, 2018). According to the inner-outer sphere theory, the exposure of surface iron ions contributes to the T 1 behavior of small IONPs.…”

pH Tunable Thin Film Gradients of Magnetic Polymer Colloids for MRI Diagnostics

“…Variation of pH of PAA and magnetic polymer colloids have affected the hydrophilicity and particle deposition of magnetic colloids on the substrate, thus ultimately relaxivity of the films [ 54 ]. T1 and T2 weighted images are related to the interaction of magnetic polymer colloids with hydrogen nuclei of water molecules in the sample [ 55 ].…”

Development of Novel Versatile Theranostic Platforms Based on Titanate Nanotubes: Towards Safe Nanocarriers for Biomedical Applications

“…Regardless, catecholbased coatings have proven their effectiveness in many cases such as substrates (Saiz-Poseu et al 2019;Cheng et al 2019) and nanoparticles (TiO2, Fe3O4, etc.) (Benyettou et al 2009;Motte et al 2011;Guenin et al 2014;Thapa et al 2018;Mohammadi et al 2020).…”