Based on the experiments on MLF and the simulations of the mixing sequences, the best approach for sensitivity-enhanced solid-state NMR experiments for C assignments appears to be hSPEPS and for side-chain assignments further than C the zTOCSY approach (at 55 kHz MAS and on a 600 MHz spectrometer). Next we evaluated the transfer efficiency on a 100% H2O back-exchanged 2 H 13 C 15 N labelled GlpG sample at 55 kHz MAS. Figure shows extracted regions of C detected 2D hCC spectra using sensitivity-enhanced (using Echo-Antiecho) and standard (using States-TPPI) pulse sequences. A comparison of the peak intensities between sensitivity-enhanced and standard zTOCSY experiments (orange vs purple in Fig. ) shows the expected increase in peak intensities by approximately a factor of 2 in the sensitivity-enhanced experiment, which corresponds to an increase in SNR by √2. We also compared the peak intensities to a spectrum recorded with standard acquisition using C9 for C- C mixing (green in Fig. ) and a spectrum recorded using sensitivityenhanced hSPEPS (dark grey in Fig. ). For most peaks investigated in GlpG, the sensitivity-enhanced zTOCSY shows the highest intensity (Fig. ) and, as expected, it also gives additional peaks coming from carbons further down the side-chain compared to hSPEPS (Fig. , see also SI Fig. for the full spectra).