Sensitivity enhancement by sequential data acquisition for 13C-direct detection NMR

13C-direct detection NMR has several advantages compared to proton detection, including a tendency relax slower and wider chemical shift range. However, the sensitivity of is much lower than that because its gyromagnetic ratio. In addition, virtual decoupling procedure often performed remove peak splitting in axis, which further reduces 1/√2. this study, enhance experiments, we developed HCACO-type new pulse sequence anti-phase (AP) in-phase (IP) signals are acquired sequentially single scan. The experiment was tested on an amino acid (valine) two proteins (streptococcal protein G B1 domain (GB1) α-synuclein). AP IP spectra were successfully obtained all cases. Using these spectra, IPAP performed, removed. increased by 1.43, 1.26 times for valine, GB1 α-synuclein, respectively, conventional HCACO experiment. another sequence, where simultaneously FID. 1.40 1.35 valine GB1, respectively. These methods potentially applicable other experiments measure one-bond correlations will extend utility method, especially structural analyses intrinsically disordered proteins.