Title:	Steady-State Free Precession sequences for high and low field NMR spectroscopy in solution: Challenges and opportunities.
Authors:	MORAES, T. B. KOCK, F. V. C. SALOME, K. S. BARISON, A. SIMPSON, A. COLNAGO, L. A.
Affiliation:	TIAGO BUENO MORAES, UNIVERSIDADE DE SAO PAULO FLAVIO VINÍCIUS CRIZ ́OSTOMO KOCK, UNIVERSITY OF TORONTO SCARBOROUGH CAMPUS KAHLIL SCHWANKA SALOME, FEDERAL UNIVERSITY OF PARANA ANDERSSON BARISON, FEDERAL UNIVERSITY OF PARANA ANDRE SIMPSON, UNIVERSITY OF TORONTO SCARBOROUGH CAMPUS LUIZ ALBERTO COLNAGO, CNPDIA.
Date Issued:	2023
Citation:	Journal of Magnetic Resonance Open, v. 14?15, 100090, 2023.
Pages:	10 p.
Description:	The receptivity of NMR spectroscopy is low when compared to other techniques. Historically, increasing the strength of the static magnetic field has been the major approach to increase NMR sensitivity. In recent years several polarization transfer protocols have been used to enhance the signal-to-noise ratio (SNR), although they require special accessories and/or sample preparation. In this paper, we consider both the challenges and opportunities of steady-state free precession (SSFP) pulse sequences as a simple and efficient alternative to enhance SNR, in standard high-resolution and benchtop low-resolution NMR spectrometers. The maximum gain in these sequences is obtained with the shortest time between the pulses (Tp). However, when Tp<T2, the SSFP signal contains FID and echo components which lead to phase, intensity, and truncation artifacts on spectra obtained by Fast Fourier transform (FT). Several phase alternation SSFP sequences were used to cancel the echo component and minimize these problems in the FT spectra. Krylov base diagonalization method (KBDM) was used to eliminate the phase and truncation problems in spectra acquired by SSFP pulse sequences and can be a viable alternative to FT. The experiments were performed in high and low resolution (bench top) NMR spectrometers and significant enhancements in SNR of low receptivity nuclei such as 13C and 15N could be achieved. The SSFP sequences were also shown to enhance SNR in nuclei with high receptivity such as 19F and 31P, in very dilute samples, as is common in environmental and biological samples.
Keywords:	SSFP Low and high field NMR SNR enhancement Benchtop NMR
ISSN:	2666-4410
DOI:	https://doi.org/10.1016/j.jmro.2022.100090
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CNPDIA)