Optimization of 13C direct detection NMR methods.

(13)C-detected experiments are still limited by their inherently lower sensitivity, as compared to the equivalent (1)H-detected experiments. Improving the sensitivity of (13)C detection methods remains a significant area of NMR research that may provide better means for studying large macromolecular systems by NMR. In this communication, we show that (13)C-detected experiments are less sensitive to the salt concentration of the sample solution than (1)H-detected experiments. In addition, acquisition can be started with anti-phase coherence, resulting in higher sensitivity due to the elimination of the final INEPT transfer step.