Detection of sub-nmol amounts of the antiviral drug favipiravir in 19 F MRI using photo-chemically induced dynamic nuclear polarization

• Published in: Scientific reports 2024-01, Vol.14 (1), p.1527
• Main Authors: Bernarding, J, Bruns, C, Prediger, I, Mützel, M, Plaumann, M
• Format: Article
• Language: English
• ISSN: 2045-2322

In biological tissues, F magnetic resonance (MR) enables the non-invasive, background-free detection of F-containing biomarkers. However, the signal-to-noise ratio (SNR) is usually low because biomarkers are typically present at low concentrations. Measurements at low magnetic fields further reduce the SNR. In a proof-of-principal study we applied LED-based photo-chemically induced dynamic nuclear polarization (photo-CIDNP) to amplify the F signal at 0.6 T. For the first time, F MR imaging (MRI) and spectroscopy (MRS) of a fully biocompatible model system containing the antiviral drug favipiravir has been successfully performed. This fluorinated drug has been used to treat Ebola and COVID-19. Since the partially cyclic reaction scheme for photo-CIDNP allows for multiple data acquisitions, averaging further improved the SNR. The mean signal gain factor for F has been estimated to be in the order of 10 . An in-plane resolution of 0.39 × 0.39 mm enabled the analysis of spatially varying degrees of hyperpolarization. The minimal detectable amount of favipiravir per voxel was estimated to about 500 pmol. The results show that F photo-CIDNP is a promising method for the non-invasive detection of suitable F-containing drugs and other compounds with very low levels of the substance.