General implementation of the ERETIC method for pulsed field gradient probe heads.
A capacitive coupling between a secondary radiofrequency (rf) channel and the gradient coil of a standard commercially available high resolution NMR spectrometer and probe head is described and used to introduce a low level exponentially damped rf signal near the frequency of the primary rf channel to serve as an external concentration standard, in analogy to the so-called ERETIC method. The stability of this inexpensive and simple to implement method, here referred to as the Pulse Into the Gradient (PIG) approach, is superb over a 14-h period and both gradient tailored water suppression and one-dimensional imaging applications are provided. Since the low level signal is introduced via the pulsed field gradient coil, the coupling is identical to that for a free induction signal and thus the method proves to be immune (within 5%) to sample ionic strength effects up to the 2M NaCl solutions explored here.
Ziarelli
Fabio
F
Aix-Marseille Université, Fédération des Sciences Chimiques, Spectropole, Marseille cedex 20, France. fabio.ziarelli@univ-cezanne.fr
Viel
Stéphane
S
Caldarelli
Stefano
S
Sobieski
Daniel N
DN
Augustine
Matthew P
MP
D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation*; D008280:Magnetics / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D014159:Transducers