Convection during routine NMR experiments can lead to substantial sensitivity losses, especially on instruments equipped with cryoprobes and during experiments involving long mixing times. Here we present a simple modification to the conventional-gradient-enhanced TOCSY NMR experiment that makes judicious use of pulsed field gradients to reverse flow encoding and restores lost signal intensity. Under typical experimental conditions, this approach can boost TOCSY sensitivity by up to an order of magnitude for a representative sample.
Caytan et al. (Sat,) studied this question.