resumo
The performance of various high-resolution 1D H-1 CRAMPS pulse schemes at moderate and high static magnetic fields (400 MHz and 800 H-1 Larmor frequencies) and spinning rates up to 35 kHz, using state-of-the-art electronics is compared. The performance of the H-1 windowed acquisition decoupling schemes, wDUMBO, wPMLG3 and wSAM3 is investigated using their effective z-rotation variants on glycine and other small biological molecules, tripeptide reduced glutathione and nucleoside uridine. H-1 CRAMPS spectra, recorded with windowed H-1-H-1 decoupling methods and fast MAS (35 kHz) and high-field are reported for the first time. H-1 spectra exhibiting outstanding resolution and completely free from any artifact are also shown. The effect on spectra quality of the decoupling rf cycle and rotor periods ratio (tau(C)/tau(R)) and the power requirements needed for each windowed H-1 CRAMPS methods are discussed. (C) 2008 Elsevier Inc. All Fights reserved.
palavras-chave
NUCLEAR-MAGNETIC-RESONANCE; HIGH-RESOLUTION H-1-NMR; MULTIPLE-PULSE NMR; ANGLE-SPINNING NMR; STATE NMR; DECOUPLING SEQUENCES; SPECTROSCOPY; ROTATION; SYMMETRY
categoria
Biochemistry & Molecular Biology; Physics; Spectroscopy
autores
Mafra, L; Coelho, C; Siegel, R; Rocha, J
nossos autores
João Rocha
Prof. Catedrático
Luís Mafra
Investigador Principalagradecimentos
This research was supported by CICECO and University of Aveiro. We also thank Funclaiao para a Ci ncia e Tecnologia (FCT) the Chemistry Department of the University of Aveiro for their general financial support and for the Post-Doc Grants (R.S. and C.C). The Portuguese NMR network (http://ptnmr.dq.ua.pt) is greatly acknowledged for allowing the access to the national high-field installation at the ITQB NMR center, hosting the 800 MHz spectrometer. We thank Dr. Pedro Lamosa for his assistance on helping us to set up the 800 MHz NMR hardware and for his generosity concerning the spectrometer time allocation. Dr. Fabien Aussenac is also acknowledged for his help in the 1H CRAMPS implementation on the new Avance III console.