An Activatable ¹⁹F MRI Molecular Probe for Sensing and Imaging of Norepinephrine

Abstract

Norepinephrine (NE), acting as both a neurotransmitter and hormone, plays a significant role in regulating the action of the brain and body. Many studies have demonstrated a strong correlation between mental disorders and aberrant NE levels. Therefore, it is of urgent demand to develop in vivo analytical methods of NE for diagnostic assessment and mechanistic investigations of mental diseases. Herein, we report a 19F MRI probe (NRFP) for sensing and imaging NE, which is constructed by conjugating a gadolinium chelate to a fluorine‐containing moiety through a NE‐responsive aromatic thiocarbonate linkage. The capacity and specificity of NRFP for detecting NE is validated with in vitro detecting/imaging experiments. Furthermore, the feasibility of NRFP for visualizing NE in animals is illustrated by ex vivo and in vivo imaging experiments, demonstrating the promising potential of NRFP for selective detection and specific imaging of NE in deep tissues of living subjects.

A polymeric 1H/19F dual-modal MRI contrast agent with a snowman-like Janus nanostructure

“…Our prior research has demonstrated that Janus-type polymeric particles exhibit a remarkable capability to modulate the local microenvironment by the strategic selection of monomers, crosslinking agents, and the degree of cross-linking. 58,59 To the best of our knowledge, most dual-modal 1 H/ 19 F MRI contrast agents utilize Gd 3+ -organic ligands as the 1 H MRI scaffold, 60 with no incorporation of nitroxide radicals in this role. Here, we introduce a novel dual-modal 1 H/ 19 F MRI contrast agent featuring a Janus asymmetric nanostructure (J-CA) (Fig.…”

“…To the best of our knowledge, most dual-modal 1 H/ 19 F MRI contrast agents utilize Gd 3+ -organic ligands as the 1 H MRI scaffold, 60 with no incorporation of nitroxide radicals in this role. Here, we introduce a novel dual-modal 1 H/ 19 F MRI contrast agent featuring a Janus asymmetric nanostructure (J-CA) (Fig.…”

Small Molecule Probes for 19F Magnetic Resonance Imaging

“…Compared to the other four types of 19 F nanoprobes, small molecule 19 F probes are of precise chemical structure, facilitating their comprehensive characterization, large-scale production, and quality evaluation. Additionally, they are generally of good aqueous solubility and relatively small size, characteristics which prevent the need for further encapsulation or modification for biological applications and permit fast renal clearance from living subjects. − Furthermore, with the powerful capacity of current synthetic chemistry, the molecular nature of these probes allows for fine-tuning of the design to optimize probe properties. As summarized in Figure a, these major advantages of small molecule 19 F MRI probes are favorable for biomedical applications and clinical translations.…”