Studies of minute quantities of natural abundance molecules using 2D heteronuclear correlation spectroscopy under 100 kHz MAS

• Published in: Solid state nuclear magnetic resonance Vol. 66-67; pp. 56 - 61
• Main Authors: Nishiyama, Y, Kobayashi, T, Malon, M, Singappuli-Arachchige, D, Slowing, I I, Pruski, M
• Format: Journal Article
• Language: English
• Published: Netherlands 01.04.2015
• Subjects: Mesoporous silica nanoparticles; HSQC; Indirect detection; Ultrafast MAS; HMQC
• ISSN: 0926-2040; 1527-3326
• DOI: 10.1016/j.ssnmr.2015.02.001

Two-dimensional (1)H{(13)C} heteronuclear correlation solid-state NMR spectra of naturally abundant solid materials are presented, acquired using the 0.75-mm magic angle spinning (MAS) probe at spinning rates up to 100 kHz. In spite of the miniscule sample volume (290 nL), high-quality HSQC-type spectra of bulk samples as well as surface-bound molecules can be obtained within hours of experimental time. The experiments are compared with those carried out at 40 kHz MAS using a 1.6-mm probe, which offered higher overall sensitivity due to a larger rotor volume. The benefits of ultrafast MAS in such experiments include superior resolution in (1)H dimension without resorting to (1)H-(1)H homonuclear RF decoupling, easy optimization, and applicability to mass-limited samples. The HMQC spectra of surface-bound species can be also acquired under 100 kHz MAS, although the dephasing of transverse magnetization has significant effect on the efficiency transfer under MAS alone.