Fomblin perfluoro polyether

The animal study was approved by the National Institute of Health Animal Care and Use Committee. Twelve 2-year-old F344 Brown Norway male rat (National Institute of Aging, Bethesda, MD) and twelve 6-week-old Sprague Dawley male rats Charles Rivers Laboratories Inc., Wilmington, MA) were used.
Once the rats were anesthetized with 1–5% isoflurane mixed with oxygen, Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA, Magnevist, Schering Berlin, Germany) contrast agent at a concentration of 0.6 mL/kg was administered intravenously. The rats were given potassium chloride 10 minutes after administration of the contrast agent to freeze the in-vivo myocardial distribution of gadolinium for subsequent ex-vivo imaging. Immediately, excised hearts were immersed in fomblin perfluoro-polyether (Solvay Solexis, West Deptford, NJ) for CMR imaging. Hearts were then fixed in a 10% Formalin solution for histology processing after the image acquisition.

Ex vivo dMRI of the same adult and P11 mouse brains was performed on a vertical 17.6 Tesla NMR spectrometer (Bruker Biospin, Billerica, MA, USA) with a Micro2.5 gradient system (maximum gradient strength = 1500 mT/m) and a 15 mm diameter transceiver volume coil. During MRI, the specimens were immersed in fomblin (Fomblin Perfluoropolyether, Solvay Solexis, Thorofare, NJ, USA) for susceptibility matching and to prevent dehydration. The temperature of the specimens was maintained at 37 °C via the spectrometer’s temperature control system. The same imaging protocol as the in vivo MRI was used, except that a higher b-value (800 s/mm²) was used to compensate for the reduced ADC in the ex vivo brains. The SNR measured in the cortex were greater than 70 for both OGSE and PGSE experiments.