Design and testing of high sensitivity microreceiver coil apparatus for nuclear magnetic resonance and imaging

We report the design and testing of a nuclear magnetic resonance (NMR) microcoil receiver apparatus, employing solenoidal microreceiver coils of dimensions of tens to hundreds of microns, using applied field of 9 T (proton resonance frequency 383 MHz). For the smallest receiver coils we attain sensitivity sufficient to observe proton NMR with signal to noise (S/N) one in a single scan applied to a similar to 10 mum(3) (10 fl) water sample, containing 7x10(11) total proton spins. We also test the dependence of the S/N on important coil parameters, including coil composition and resistivity, turn spacing, and lead lengths. (C) 2001 American Institute of Physics.