Hyperpolarized 15N-pyridine derivatives as pH-sensitive MRI agents

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Chemical Biology
• Medical Diagnostics

Background:

• Accurate pH monitoring is crucial for diagnosing and predicting disease progression.
• Existing MRI agents lack the sensitivity and speed required for real-time pH tracking.

Purpose of the Study:

• To investigate hyperpolarized nitrogen-15 (15N) pyridine derivatives as novel, ultrasensitive pH-sensitive imaging probes.
• To evaluate their potential for diagnostic and prognostic applications in various diseases.

Main Methods:

• Utilized standard dynamic nuclear polarization (DNP) techniques for high-level polarization of 15N-pyridine derivatives.
• Measured the pH sensitivity of the 15N chemical shifts of these probes.

Main Results:

• Demonstrated that 15N chemical shifts of pyridine derivatives are highly sensitive to pH changes.
• Observed sharp 15N resonances and significant chemical shift differences (>90 ppm) between free base and protonated forms.
• Confirmed suitability for detecting subtle pH variations near physiological levels.

Conclusions:

• Hyperpolarized 15N-pyridine derivatives are promising candidates for ultrasensitive, rapid pH monitoring using MRI.
• These probes have significant potential for improving diagnostic and prognostic capabilities in medicine.