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Nimerovsky E, Varkey AC, Kim M, Becker S, Andreas LB. Simplified Preservation of Equivalent Pathways Spectroscopy. JACS AU 2023; 3:2763-2771. [PMID: 37885577 PMCID: PMC10598565 DOI: 10.1021/jacsau.3c00312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/27/2023] [Accepted: 09/27/2023] [Indexed: 10/28/2023]
Abstract
Inspired by the recently proposed transverse mixing optimal control pulses (TROP) approach for improving signal in multidimensional magic-angle spinning (MAS) NMR experiments, we present simplified preservation of equivalent pathways spectroscopy (SPEPS). It transfers both transverse components of magnetization that occur during indirect evolutions, theoretically enabling a √2 improvement in sensitivity for each such dimension. We compare SPEPS transfer with TROP and cross-polarization (CP) using membrane protein and fibril samples at MAS of 55 and 100 kHz. In three-dimensional (3D) (H)CANH spectra, SPEPS outperformed TROP and CP by factors of on average 1.16 and 1.69, respectively, for the membrane protein, but only a marginal improvement of 1.09 was observed for the fibril. These differences are discussed, making note of the longer transfer time used for CP, 14 ms, as compared with 2.9 and 3.6 ms for SPEPS and TROP, respectively. Using SPEPS for two transfers in the 3D (H)CANCO experiment resulted in an even larger benefit in signal intensity, with an average improvement of 1.82 as compared with CP. This results in multifold time savings, in particular considering the weaker peaks that are observed to benefit the most from SPEPS.
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Affiliation(s)
- Evgeny Nimerovsky
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Abel Cherian Varkey
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Myeongkyu Kim
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Stefan Becker
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Loren B. Andreas
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
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2
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Blahut J, Brandl MJ, Pradhan T, Reif B, Tošner Z. Sensitivity-Enhanced Multidimensional Solid-State NMR Spectroscopy by Optimal-Control-Based Transverse Mixing Sequences. J Am Chem Soc 2022; 144:17336-17340. [PMID: 36074981 DOI: 10.1021/jacs.2c06568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recently, proton-detected magic-angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) spectroscopy has become an attractive tool to study the structure and dynamics of insoluble proteins at atomic resolution. The sensitivity of the employed multidimensional experiments can be systematically improved when both transversal components of the magnetization are transferred simultaneously after an evolution period. The method of preservation of equivalent pathways has been explored in solution-state NMR; however, it does not find widespread application due to relaxation issues connected with increased molecular size. We present here for the first time heteronuclear transverse mixing sequences for correlation experiments at moderate and fast MAS frequencies. Optimal control allows to boost the signal-to-noise ratio (SNR) beyond the expected factor of 2 for each indirect dimension. In addition to the carbon-detected sensitivity-enhanced 2D NCA experiment, we present a novel proton-detected, doubly sensitivity-enhanced 3D hCANH pulse sequence for which we observe a 3-fold improvement in SNR compared to the conventional experimental implementation. The sensitivity gain turned out to be essential to unambiguously characterize a minor fibril polymorph of a human lambda-III immunoglobulin light chain protein that escaped detection so far.
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Affiliation(s)
- Jan Blahut
- Department of Chemistry, Faculty of Science, Charles University, Albertov 6, 12842 Prague, Czech Republic.,Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo nám. 2, 16610, Prague, Czech Republic
| | - Matthias J Brandl
- Bayerisches NMR Zentrum (BNMRZ) at Department Chemie, Technische Universität München (TUM), 85747 Garching, Germany
| | - Tejaswini Pradhan
- Bayerisches NMR Zentrum (BNMRZ) at Department Chemie, Technische Universität München (TUM), 85747 Garching, Germany
| | - Bernd Reif
- Bayerisches NMR Zentrum (BNMRZ) at Department Chemie, Technische Universität München (TUM), 85747 Garching, Germany.,Helmholtz-Zentrum München (HMGU), Deutsches Forschungszentrum für Gesundheit und Umwelt, 85764 Neuherberg, Germany
| | - Zdeněk Tošner
- Department of Chemistry, Faculty of Science, Charles University, Albertov 6, 12842 Prague, Czech Republic
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Lin J, Griffin RG, Nielsen NC, Khaneja N. Three pulse recoupling and phase jump matching. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 263:172-183. [PMID: 26777742 PMCID: PMC4959450 DOI: 10.1016/j.jmr.2015.11.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Revised: 11/01/2015] [Accepted: 11/21/2015] [Indexed: 06/05/2023]
Abstract
The paper describes a family of novel recoupling pulse sequences, called three pulse recoupling. These pulse sequences can be employed for both homonuclear and heteronuclear recoupling experiments and are robust to dispersion in chemical shifts and rf-inhomogeneity. These recoupling pulse sequences can be used in design of two-dimensional solid state NMR experiments that use powdered dephased antiphase coherence (γ preparation) to encode chemical shifts in the indirect dimension. Both components of this chemical shift encoded gamma-prepared states can be refocused into inphase coherence by a recoupling element. This helps to achieve sensitivity enhancement in 2D NMR experiments by quadrature detection.
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Affiliation(s)
- James Lin
- School of Engineering and Applied Sciences, United States
| | - R G Griffin
- Francis Bitter Magnet Lab, Department of Chemistry, MIT, United States
| | | | - Navin Khaneja
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, United States.
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4
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Gopinath T, Veglia G. Multiple acquisition of magic angle spinning solid-state NMR experiments using one receiver: application to microcrystalline and membrane protein preparations. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 253:143-53. [PMID: 25797011 PMCID: PMC4399235 DOI: 10.1016/j.jmr.2015.01.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 01/02/2015] [Accepted: 01/04/2015] [Indexed: 05/05/2023]
Abstract
Solid-state NMR spectroscopy of proteins is a notoriously low-throughput technique. Relatively low-sensitivity and poor resolution of protein samples require long acquisition times for multidimensional NMR experiments. To speed up data acquisition, we developed a family of experiments called Polarization Optimized Experiments (POE), in which we utilized the orphan spin operators that are discarded in classical multidimensional NMR experiments, recovering them to allow simultaneous acquisition of multiple 2D and 3D experiments, all while using conventional probes with spectrometers equipped with one receiver. POE allow the concatenation of multiple 2D or 3D pulse sequences into a single experiment, thus potentially combining all of the aforementioned advances, boosting the capability of ssNMR spectrometers at least two-fold without the addition of any hardware. In this perspective, we describe the first generation of POE, such as dual acquisition MAS (or DUMAS) methods, and then illustrate the evolution of these experiments into MEIOSIS, a method that enables the simultaneous acquisition of multiple 2D and 3D spectra. Using these new pulse schemes for the solid-state NMR investigation of biopolymers makes it possible to obtain sequential resonance assignments, as well as distance restraints, in about half the experimental time. While designed for acquisition of heteronuclei, these new experiments can be easily implemented for proton detection and coupled with other recent advancements, such as dynamic nuclear polarization (DNP), to improve signal to noise. Finally, we illustrate the application of these methods to microcrystalline protein preparations as well as single and multi-span membrane proteins reconstituted in lipid membranes.
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Affiliation(s)
- T Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States; Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, United States.
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Gopinath T, Veglia G. 3D DUMAS: simultaneous acquisition of three-dimensional magic angle spinning solid-state NMR experiments of proteins. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2012; 220:79-84. [PMID: 22698806 PMCID: PMC3487463 DOI: 10.1016/j.jmr.2012.04.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 04/13/2012] [Indexed: 05/15/2023]
Abstract
Using the DUMAS (Dual acquisition Magic Angle Spinning) solid-state NMR approach, we created new pulse schemes that enable the simultaneous acquisition of three dimensional (3D) experiments on uniformly (13)C, (15)N labeled proteins. These new experiments exploit the simultaneous cross-polarization (SIM-CP) from (1)H to (13)C and (15)N to acquire two 3D experiments simultaneously. This is made possible by bidirectional polarization transfer between (13)C and (15)N and the long living (15)N z-polarization in solid state NMR. To demonstrate the power of this approach, four 3D pulse sequences (NCACX, CANCO, NCOCX, CON(CA)CX) are combined into two pulse sequences (3D DUMAS-NCACX-CANCO, 3D DUMAS-NCOCX-CON(CA)CX) that allow simultaneous acquisition of these experiments, reducing the experimental time by approximately half. Importantly, the 3D DUMAS-NCACX-CANCO experiment alone makes it possible to obtain the majority of the backbone sequential resonance assignments for microcrystalline U-(13)C,(15)N ubiquitin. The DUMAS approach is general and applicable to many 3D experiments, nearly doubling the performance of NMR spectrometers.
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Affiliation(s)
- T. Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455
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Gopinath T, Veglia G. Dual acquisition magic-angle spinning solid-state NMR-spectroscopy: simultaneous acquisition of multidimensional spectra of biomacromolecules. Angew Chem Int Ed Engl 2012; 51:2731-5. [PMID: 22311700 PMCID: PMC3513283 DOI: 10.1002/anie.201108132] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Indexed: 11/05/2022]
Abstract
Fast data collection: a general method for dual data acquisition of multidimensional magic-angle spinning solid-state NMR experiments is presented. The method uses a simultaneous Hartmann-Hahn cross-polarization from (1)H to (13)C and (15)N nuclei and exploits the long-living (15)N polarization for parallel acquisition of two multidimensional experiments.
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Affiliation(s)
- T. Gopinath
- Department of Chemistry and Department of Biochemistry, Molecular Biology and Biophysics, 321 Church St. SE, Minneapolis, MN 55455 USA
| | - Gianluigi Veglia
- Department of Chemistry and Department of Biochemistry, Molecular Biology and Biophysics, 321 Church St. SE, Minneapolis, MN 55455 USA
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7
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Gopinath T, Veglia G. Dual Acquisition Magic-Angle Spinning Solid-State NMR-Spectroscopy: Simultaneous Acquisition of Multidimensional Spectra of Biomacromolecules. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201108132] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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8
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Lin J, Griffin R, Khaneja N. Recoupling in solid state NMR using γ prepared states and phase matching. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 212:402-411. [PMID: 21889380 PMCID: PMC4134438 DOI: 10.1016/j.jmr.2011.07.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 07/25/2011] [Accepted: 07/28/2011] [Indexed: 05/27/2023]
Abstract
The paper describes two-dimensional solid state NMR experiments that use powdered dephased antiphase coherence (γ preparation) to encode chemical shifts in the indirect dimension. Both components of this chemical shift encoded gamma-prepared states can be refocused into inphase coherence by a recoupling element. This helps to achieve sensitivity enhancement in 2D NMR experiments by quadrature detection. The powder dependence of the gamma-prepared states allows for manipulating them by suitable insertion of delays in the recoupling periods. This helps to design experiments that suppress diagonal peaks in 2D spectra, leading to improved resolution. We describe some new phase modulated heteronuclear and homonuclear recoupling pulse sequences that simplify the implementation of the described experiments based on γ prepared states. Recoupling in the heteronuclear spin system is achieved by matching the difference in the amplitude of the sine/cosine modulated phase on the two rf-channels to the spinning frequency while maintaining the same power on the two rf-channels.
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Affiliation(s)
- James Lin
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, United States
| | - R.G. Griffin
- Francis Bitter Magnet Lab, Department of Chemistry, MIT, United States
| | - Navin Khaneja
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, United States
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9
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Straasø LA, Nielsen NC. Recoupling of native homonuclear dipolar couplings in magic-angle-spinning solid-state NMR by the double-oscillating field technique. J Chem Phys 2010; 133:064501. [DOI: 10.1063/1.3464334] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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10
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Gopinath T, Traaseth NJ, Mote K, Veglia G. Sensitivity enhanced heteronuclear correlation spectroscopy in multidimensional solid-state NMR of oriented systems via chemical shift coherences. J Am Chem Soc 2010; 132:5357-63. [PMID: 20345172 PMCID: PMC3328406 DOI: 10.1021/ja905991s] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present new sensitivity enhanced schemes for heteronuclear correlation spectroscopy (HETCOR) in solid-state NMR of oriented systems. These schemes will enhance the sensitivity of the HETCOR by 40% for the two-dimensional experiments (SE-HETCOR) and up to 180% for the 3D HETCOR-separated local field version (SE-PISEMAI-HETCOR). The signal enhancement is demonstrated for a single crystal of ((15)N)N-acetylleucine and the integral membrane protein sarcolipin oriented in lipid bicelles. These methods will significantly reduce the time needed to acquire multidimensional experiments for membrane proteins oriented in magnetically or mechanically aligned lipid bilayers as well as liquid crystalline materials.
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Affiliation(s)
- T. Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | | | - Kaustubh Mote
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455
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11
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Gopinath T, Veglia G. Sensitivity enhancement in static solid-state NMR experiments via single- and multiple-quantum dipolar coherences. J Am Chem Soc 2009; 131:5754-6. [PMID: 19351170 PMCID: PMC3481552 DOI: 10.1021/ja900096d] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present a new method for enhancing the sensitivity in static solid-state NMR experiments for a gain in signal-to-noise ratio of up to 40%. This sensitivity enhancement is different from the corresponding solution NMR sensitivity enhancement schemes and is achieved by combining single- and multiple-quantum dipolar coherences. While this new approach is demonstrated for the polarization inversion spin exchange at magic angle (PISEMA) experiment, it can be generalized to the other separated local field experiments for solid-state NMR spectroscopy. This method will have a direct impact on solid-state NMR spectroscopy of liquid crystals as well as of membrane proteins aligned in lipid membranes.
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Affiliation(s)
- T. Gopinath
- Department of Chemistry andDepartment of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - Gianluigi Veglia
- Department of Chemistry andDepartment of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
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12
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Qian C, Thureau P, Martin RW. Variable angle spinning (VAS) experiments for strongly oriented systems: methods development and preliminary results. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2008; 46:351-355. [PMID: 18306174 DOI: 10.1002/mrc.2170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Variable angle spinning (VAS) experiments provide a useful method for measuring long-range dipolar couplings and obtaining isotropic-anisotropic correlation spectra. These experiments make it possible to obtain correlations between isotropic and anisotropic spectra without altering the chemical composition of the sample. They also allow working with very strongly oriented systems that are not accessible to solution-state techniques. In this communication, we discuss recent hardware developments in our laboratory and show representative data from small molecules in strongly oriented liquid-crystalline samples.
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Affiliation(s)
- Chunqi Qian
- Department of Chemistry, Materials Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720, USA
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Herbst C, Riedel K, Leppert J, Ohlenschläger O, Görlach M, Ramachandran R. 13C-13C chemical shift correlation in rotating solids without 1H decoupling during mixing. Chemphyschem 2007; 8:1770-3. [PMID: 17665381 DOI: 10.1002/cphc.200700234] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Christian Herbst
- Molecular Biophysics/NMR spectroscopy Leibniz Institute for Age Research, Fritz Lipmann Institute, Beutenbergstrasse 11, 07745 Jena, Germany
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Khaneja N. Sensitivity enhanced recoupling experiments in solid-state NMR by gamma preparation. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 183:242-51. [PMID: 16997586 DOI: 10.1016/j.jmr.2006.08.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Revised: 08/25/2006] [Accepted: 08/28/2006] [Indexed: 05/11/2023]
Abstract
In this paper, we introduce a class of dipolar recoupling experiments under magic angle spinning (MAS), which use gamma dependent antiphase polarization during the t1 evolution period. We show that this helps us to design dipolar recoupling experiments that transfer both components of the transverse magnetization of spin S to a coupled spin I in the mixing step of a 2D NMR experiment. We show that it is possible to design such transfer schemes and make them insensitive to the orientation dependency of the couplings in powders. This helps us to develop sensitivity enhanced 2D NMR experiments of powder samples under MAS.
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Affiliation(s)
- Navin Khaneja
- Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
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Tosner Z, Glaser SJ, Khaneja N, Nielsen NC. Effective Hamiltonians by optimal control: Solid-state NMR double-quantum planar and isotropic dipolar recoupling. J Chem Phys 2006; 125:184502. [PMID: 17115760 DOI: 10.1063/1.2366703] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report the use of optimal control algorithms for tailoring the effective Hamiltonians in nuclear magnetic resonance (NMR) spectroscopy through sophisticated radio-frequency (rf) pulse irradiation. Specifically, we address dipolar recoupling in solid-state NMR of powder samples for which case pulse sequences offering evolution under planar double-quantum and isotropic mixing dipolar coupling Hamiltonians are designed. The pulse sequences are constructed numerically to cope with a range of experimental conditions such as inhomogeneous rf fields, spread of chemical shifts, the intrinsic orientation dependencies of powder samples, and sample spinning. While the vast majority of previous dipolar recoupling sequences are operating through planar double-or zero-quantum effective Hamiltonians, we present here not only improved variants of such experiments but also for the first time homonuclear isotropic mixing sequences which transfers all I(x), I(y), and I(z) polarizations from one spin to the same operators on another spin simultaneously and with equal efficiency. This property may be exploited to increase the signal-to-noise ratio of two-dimensional experiments by a factor of square root 2 compared to conventional solid-state methods otherwise showing the same efficiency. The sequences are tested numerically and experimentally for a powder of (13)C(alpha),(13)C(beta)-L-alanine and demonstrate substantial sensitivity gains over previous dipolar recoupling experiments.
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Affiliation(s)
- Zdenek Tosner
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, DK-8000 Aarhus C, Denmark
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