Pure Shift NMR

Suppressing multiplet structure in 1H NMR spectra offers a large improvement in spectral resolution (see below), each multiplet collapsing down to a single line at the appropriate chemical shift. The improvement in resolution is equivalent to using a 5 GHz spectrometer rather than a 500 MHz.

(Top) normal and (bottom) pure shift 500 MHz 1H spectra of estradiol. Taken from Foroozandeh et al..

Such “pure shift” techniques are readily extended to multidimensional methods. For example, in DOSY the ability to resolve different rates of diffusion depends crucially on resolving signals in the NMR spectrum. Unresolved signals lead to compromise apparent diffusion coefficients, so pure shift DOSY can make DOSY spectra much easier to interpret.

(Left) normal and (right) pure shift 400 MHz 1H DOSY spectra of a mixture of vitamin D3 and provitamin D3. Collapsing multiplet structure avoids signal overlap and leads to all signals appearing with the correct diffusion coefficient. Taken from Foroozandeh et al..

If pure shift methods are combined with covariance processing it is possible to produce multidimensional spectra in which all signals appear as singlets, greatly simplifying results.

(Left) normal and (right) pure shift 500 MHz 1H TOCSY spectra of estradiol. Taken from Foroozandehet al..

Our research in this field is focused on the development and the application of novel pure shift NMR techniques. Over the last years we have published several new pure shift methods that have become very popular such as PSYCHE and real-time HSQC, among others. All our pulse sequences codes and ancillary material that allow these methods to be implemented immediately on standard NMR spectrometers are freely available here. There is also available a pure shift NMR package which include pulse sequences, sample experimental data and copies of slides for the talks given at our 2017 workshop on pure shift NMR.

Pure shift publication from our group:

Ultraclean pure shift NMR. Moutzouri P, Chen Y, Foroozandeh M, Kiraly P, Phillips AR, Coombes SR, Nilsson M, Morris GA. 2017. Chemical Communications. 53:10188-10191.

Anatomising proton NMR spectra with pure shift 2D J-spectroscopy: A cautionary tale. Kiraly P, Foroozandeh M, Nilsson M, Morris GA. 2017. Chemical Physics Letters. 683:398-403.

Pure shift 1H NMR: what is next? Castañar L. 2017 Magnetic Resonance in Chemistry. 55:47–53.

Ultrahigh-Resolution Diffusion-Ordered Spectroscopy. Foroozandeh M, Castañar L, Martins LG, Sinnaeve D, Dal Poggetto G, Tormena CF, Adams RW, Morris GA, Nilsson M. 2016. Angewandte Chemie International Edition. 55(50):15579–15582.

A new tool for NMR analysis of complex systems: selective pure shift TOCSY. Poggetto DG, Castañar L, Morris GA, Nilsson M. 2016. RSC Advances. 6(102):100063-100066.

Real-time broadband proton-homodecoupled CLIP/CLAP-HSQC for automated measurement of heteronuclear one-bond coupling constants. Timári I, Kaltschnee L, Raics MH, Roth F, Bell NGA, Adams RW, Nilsson M, Uhrín D, Morris GA, Thiele CM and Kövér KE. 2016. RSC Advances. 6(91):87848-87855.

Extraction of distance restraints from pure shift NOE experiments. Kaltschnee L, Knoll K, Schmidts V, Adams RW, Nilsson M, Morris GA, Thiele CM. 2016. Journal of Magnetic Resonance. 271:99-109.

A General Method for Extracting Individual Coupling Constants from Crowded 1H NMR Spectra. Sinnaeve D, Foroozandeh M, Nilsson M, Morris GA.2016. Angewandte Chemie International Edition. 55(3):1090-1093.

Measuring couplings in crowded NMR spectra: pure shift NMR with multiplet analysis. Foroozandeh, M, Adams RW, Kiraly P, Nilsson M, Morris GA. 2015. Chemical Communications. 51(84):15410-15413.

Ultra-high dispersion NMR reveals new levels of detail. Aguilar, JA, Kiraly P, Adams RW, Bonneau M, Grayson EJ, Nilsson M, Kenwright AM, Morris GA. 2015. RSC Advances. 5: 52902-52906.

Minimising Research Bottlenecks by Decluttering NMR Spectra. Aguilar, JA, Cassani J, Delbianco M, Adams RW, Nilsson M, Morris GA. 2015. Chemistry - A European Journal. 21(17):6623-6630.

Precise Measurement of Long-Range Heteronuclear Coupling Constants by a Novel Broadband Proton-Proton-Decoupled CPMG-HSQMBC Method. Timári, I, Illyés TZ, Adams RW, Nilsson M, Szilágyi L, Morris GA, Kövér KE. 2015. Chemistry - A European Journal. 21(8):3472-3479.

Real-time pure shift 15N HSQC of proteins: a real improvement in resolution and sensitivity. Kiraly, P, Adams RW, Paudel L, Foroozandeh M, Aguilar JA, Timári I, Cliff MJ, Nilsson M, Sándor P, Batta G Waltho JP, Kövér KE, Morris GA. 2015. Journal of Biomolecular NMR.

eMagRes: Pure Shift NMR Spectroscopy. Adams, RW. 2014:295-310.

Ultrahigh-Resolution Total Correlation NMR Spectroscopy. Foroozandeh, M, Adams RW, Nilsson M, Morris GA. 2014. Journal of the American Chemical Society. 136(34):11867-11869.

Ultrahigh-Resolution NMR Spectroscopy. Foroozandeh M, Adams RW, Meharry NJ, Jeannerat D, Nilsson M, Morris GA. 2014. Angewandte Chemie International Edition, 53:6990-6992.

Diastereomeric ratio determination by high sensitivity band-selective pure shift NMR spectroscopy. Adams, RW, Byrne L, Kiraly P, Foroozandeh M, Paudel L, Nilsson M, Clayden J, Morris GA. 2014. Chemical Communications. 50(19):2512.

Perfecting, pure shift HSQC: full homodecoupling for accurate and precise determination of heteronuclear couplings.Kaltschnee, L, Kolmer A, Timari I, Schmidts V, Adams RW, Nilsson M, Köver KE, Morris GA, Thiele CM. 2014. Chemical Communications. 50:2512-2514.

Pure shift, 1H NMR, a robust method for revealing heteronuclear couplings in complex spectra. Aguilar, JA, Morris GA, Kenwright AM. 2014. RSC Advances. 4(16):8278.

Accurate determination of one-bond heteronuclear coupling constants with “pure shift” broadband proton-decoupled CLIP/CLAP-HSQC experiments. Timári, I, Kaltschnee L, Kolmer A, Adams RW, Nilsson M, Thiele CM, Morris GA, Kövér KE. 2014. Journal of Magnetic Resonance. 239:130-138.

Simultaneously Enhancing Spectral Resolution and Sensitivity in Heteronuclear Correlation NMR Spectroscopy. Paudel, L, Adams RW, Kiraly P, Aguilar JA, Foroozandeh M, Cliff MJ, Nilsson M, Sándor P, Waltho JP, Morris GA. 2013. Angewandte Chemie International Edition. 52(44):11616-11619.

Decoupling Two-Dimensional NMR Spectroscopy in Both Dimensions: Pure Shift NOESY and COSY. Aguilar, JA, Colbourne A, Cassani J, Nilsson M, Morris GA. 2012. Angewandte Chemie International Edition. 51:6460-6463.

Simple Proton Spectra from Complex Spin Systems: Pure Shift NMR Spectroscopy Using BIRD. Aguilar, JA, Nilsson M, Morris GA. 2011. Angewandte Chemie International Edition.

True Chemical Shift Correlation Maps: A TOCSY Experiment with Pure Shifts in Both Dimensions. Morris, GA, Aguilar, JA, Evans, R, Haiber, S, Nilsson, M. 2010. J. Am. Chem. Soc. 132, 12770-12772.

Pure Shift 1H NMR: A Resolution of the Resolution Problem? Aguilar, JA, Faulkner, S, Nilsson, M, Morris GA. 2010. Angewandte Chemie International Edition. 49:3901-3903.

Pure shift proton DOSY: diffusion-ordered 1H spectra without multiplet structure. Nilsson, M, Morris, GA. 2007Chem. Commun. 2007: 933-935.