![Author ORCID: We display the ORCID iD icon alongside authors names on our website to acknowledge that the ORCiD has been authenticated when entered by the user. To view the users ORCiD record click the icon. [opens in a new tab]](https://chemrxiv.org/engage/assets/public/chemrxiv/images/logos/orcid.png)
Abstract
Recently developed homonuclear Transverse mixing Optimal control Pulses (hTROP) revealed an elegant way to enhance the detected signal in multi-dimensional magic-angle spinning (MAS) NMR experiments. Inspired by their work, we present two homonuclear simplified preservation of equivalent pathways spectroscopy (hSPEPS) sequences for recoupling CA-CO and CA-CB dipolar couplings under fast and ultra-fast MAS rates, theoretically enabling a √2 improvement in sensitivity for each indirect dimension. The efficiencies of hSPEPS is evaluated for non-deuterated samples of influenza A M2 and bacterial rhomboid protease GlpG under two different external magnetic fields (600 MHz and 1200 MHz) and MAS rates (55 kHz and 100 kHz). 3D (H)CA(CO)NH, 3D (H)CO(CA)NH and 3D (H)CB(CA)NH spectra demonstrate the high robustness of hSPEPS elements to excite carbon-carbon correlations, especially in the (H)CB(CA)NH spectrum, where hSPEPS outperforms the J-based sequence by a factor of, on average, 2.85.
