Single Fluorinated Agent for Multiplexed ¹⁹ F-MRI with Micromolar Detectability Based on Dynamic Exchange

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Nuclear Magnetic Resonance (NMR) Spectroscopy
• Biomedical Engineering
• Supramolecular Chemistry

Background:

• Weak thermal polarization of nuclear spins limits MRI sensitivity, particularly for fluorine-19 MRI (¹⁹ F-MRI).
• Current ¹⁹ F-MRI struggles to map very low target concentrations, hindering applications like multiplexed imaging.
• Enhanced sensitivity is crucial for expanding ¹⁹ F-MRI's diagnostic and research capabilities.

Purpose of the Study:

• To significantly enhance the sensitivity of ¹⁹ F-MRI.
• To develop a method for detecting low concentrations of targets using ¹⁹ F-MRI.
• To demonstrate multicolor imaging and potential in vivo translatability of the enhanced technique.

Main Methods:

• Applied chemical exchange saturation transfer (CEST) principles within the ¹⁹ F-MRI framework.
• Utilized host-guest supramolecular assemblies and dynamic interactions (termed GEST) for signal amplification.
• Employed an inhalable fluorinated anesthetic as a single ¹⁹ F-probe for dual-target detection.

Main Results:

• Achieved a 900-fold signal amplification for a biocompatible fluorinated agent.
• Demonstrated concurrent detection of micromolar levels of two distinct targets using a single ¹⁹ F-probe.
• Presented the potential for multicolor imaging capabilities.

Conclusions:

• The GEST approach significantly boosts ¹⁹ F-MRI sensitivity, enabling detection of previously undetectable low concentrations.
• This method offers a promising platform for multicolor imaging and has potential for in vivo applications.
• Further development of GEST could broaden ¹⁹ F-MRI's applicability in biomedical research and diagnostics.