High-Contrast and Fast-Removable 19 F-MRI Labels with Perfluoro-tert-Butyl Substituents.

ABSTRACT

19 F MRI is a unique technique for tracking and quantifying the indicator (19 F-MRI label) in vivo without the use of ionizing radiation. Here we report new 19 F-MRI labels, which are compounds with perfluoro-tert-butyl groups 1,2-bis(perfluoro-tert-butoxy)ethane (C10 F18 H4 O2 ) and 1,3-bis(perfluoro-tert-butyl)propane (C11 F18 H6 ). Both substances contain 18 equivalent 19 F atoms, constituting 68.67 % and 71.25 % of the molecule, respectively. The emulsions with 19 F molecules were prepared and used in 19 F MRI studies in laboratory rats in vivo. The substances demonstrated high contrast properties, good biological inertness and the ability to be rapidly eliminated from the body. We showed that at a dose of 0.34 mg/g of body weight in rats, the time for complete elimination of C10 F18 H4 O2 and C11 F18 H6 is ∼30 days. The results turned out to be promising for the use of the presented compounds in 19 F MRI applications, especially since they are quite easy to synthesize.