Parallel-plate RF resonator imaging of chemical shift resolved capillary flow

Magnetic resonance imaging has been introduced to study flow in microchannels using pure phase spatial encoding with a microfabricated parallel-plate nuclear magnetic resonance (NMR) probe. The NMR probe and pure phase spatial encoding enhance the sensitivity and resolution of the measurement. In this paper, H-1 NMR spectra and images were acquired at 100 MHz. The B-1 magnetic field is homogeneous and the signal-to-noise ratio of 30 mu l doped water for a single scan is 8 x 10(4). The high sensitivity of the probe enables velocity mapping of the fluids in the micro-channel with a spatial resolution of 13 x 13 mu m. The parallel-plate probe with pure phase encoding permits the acquisition of NMR spectra; therefore, chemical shift resolved velocity mapping was also undertaken. Results are presented which show separate velocity maps for water and methanol flowing through a straight circular micro-channel. Finally, future performance of these techniques for the study of microfluidics is extrapolated and discussed. (C) 2010 Elsevier Inc. All rights reserved.