Dual resonant birdcage coils for1H detected13C microscopic imaging at 11.7 T

Liquid state, rotating frame cross polarisation experiments are very sensitive to RF field inhomogeneity. In this work, we present an easily fabricated, co-resident high- and low-pass linear birdcage resonator, optimised to perform liquid state rotating frame polarisation transfer at¹H and¹³C frequencies. Both the RF fields have been experimentally mapped, and used to validate the spatial signal dependence of a proton detected,¹³C image. The predicted performance was then confirmed using PRAWN-based, cyclic J-cross polarisation (CYCLCROP) imaging. A novel variant of a B₁-field mapping approach is also presented, using the signal enhancement of the CYCLCROP sequence to generate proton detected,¹³C field maps.