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Nawrocka EK, Jadwiszczak M, Leszczyński PJ, Kazimierczuk K. Supporting the assignment of NMR spectra with variable-temperature experiments. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:479-485. [PMID: 38303612 DOI: 10.1002/mrc.5433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 02/03/2024]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is one of the most powerful tools in analytical chemistry. An important step in the analysis of NMR data is the assignment of resonance frequencies to the corresponding atoms in the molecule being investigated. The traditional approach considers the spectrum's characteristic parameters: chemical shift values, internuclear couplings, and peak intensities. In this paper, we show how to support the process of assigning a series of spectra of similar organic compounds by using temperature coefficients, that is, the rates of change in chemical shift values associated with given changes in temperature.
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Affiliation(s)
- Ewa K Nawrocka
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
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2
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Romero JA, Kazimierczuk K, Kasprzak P. Optimizing measurements of linear changes of NMR signal parameters. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 360:107632. [PMID: 38382405 DOI: 10.1016/j.jmr.2024.107632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/24/2024] [Accepted: 01/31/2024] [Indexed: 02/23/2024]
Abstract
Serial NMR experiments are commonly applied in variable-temperature studies, reaction monitoring, and other tasks. The resonance frequencies often shift linearly over the series, and the shift rates help to characterize the studied system. They can be determined using a classical fitting of peak positions or a more advanced method of Radon transform. However, the optimal procedure for data collection remains to be determined. In this paper, we discuss how to invest experimental time, i.e., whether to measure more scans at the expense of the number of spectra or vice versa. The results indicate that classical fitting provides slightly less error than the Radon transform, although the latter can be the method of choice for a low signal-to-noise ratio. We demonstrate this fact through theoretical consideration, simulations, and an experiment. Finally, we extend our considerations to the linear fitting of peak amplitudes. Interestingly, the optimal setup for measuring peak height changes differs from the one for resonance frequency changes - fewer spectra with more scans provide better results.
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Affiliation(s)
- Javier Agustin Romero
- Centre of New Technologies, University of Warsaw, Banacha 2C, Warsaw, 02-097, Poland
| | | | - Paweł Kasprzak
- Faculty of Physics, University of Warsaw, Pasteura 5, Warsaw, 02-093, Poland.
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3
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Shchukina A, Schwarz TC, Nowakowski M, Konrat R, Kazimierczuk K. Non-uniform sampling of similar NMR spectra and its application to studies of the interaction between alpha-synuclein and liposomes. JOURNAL OF BIOMOLECULAR NMR 2023; 77:149-163. [PMID: 37237169 PMCID: PMC10406685 DOI: 10.1007/s10858-023-00418-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023]
Abstract
The accelerated acquisition of multidimensional NMR spectra using sparse non-uniform sampling (NUS) has been widely adopted in recent years. The key concept in NUS is that a major part of the data is omitted during measurement, and then reconstructed using, for example, compressed sensing (CS) methods. CS requires spectra to be compressible, that is, they should contain relatively few "significant" points. The more compressible the spectrum, the fewer experimental NUS points needed in order for it to be accurately reconstructed. In this paper we show that the CS processing of similar spectra can be enhanced by reconstructing only the differences between them. Accurate reconstruction can be obtained at lower sampling levels as the difference is sparser than the spectrum itself. In many situations this method is superior to "conventional" compressed sensing. We exemplify the concept of "difference CS" with one such case-the study of alpha-synuclein binding to liposomes and its dependence on temperature. To obtain information on temperature-dependent transitions between different states, we need to acquire several dozen spectra at various temperatures, with and without the presence of liposomes. Our detailed investigation reveals that changes in the binding modes of the alpha-synuclein ensemble are not only temperature-dependent but also show non-linear behavior in their transitions. Our proposed CS processing approach dramatically reduces the number of NUS points required and thus significantly shortens the experimental time.
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Affiliation(s)
- Alexandra Shchukina
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland
| | - Thomas C Schwarz
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna BioCenter Campus 5, 1030, Vienna, Austria
| | - Michał Nowakowski
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland
| | - Robert Konrat
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna BioCenter Campus 5, 1030, Vienna, Austria
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4
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Gołowicz D, Shchukina A, Kazimierczuk K. Enhanced Nuclear Magnetic Resonance Spectroscopy with Isotropic Mixing as a Pseudodimension. Anal Chem 2022; 94:9114-9121. [PMID: 35695926 PMCID: PMC9244872 DOI: 10.1021/acs.analchem.2c01471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Chemical analysis based on liquid-state nuclear magnetic resonance spectroscopy exploits numerous observables, mainly chemical shifts, relaxation rates, and internuclear coupling constants. Regarding the latter, the efficiencies of internuclear coherence transfers may be encoded in spectral peak intensities. The dependencies of these intensities on the experimental parameter that influences the transfer, for example, mixing time, are an important source of structural information. Yet, they are costly to measure and difficult to analyze. Here, we show that peak intensity build-up curves in two-dimensional total correlation spectroscopy (2D TOCSY) experiments may be quickly measured by employing nonuniform sampling and that their analysis can be effective if supported by quantum mechanical calculations. Thus, such curves can be used to form a new, third pseudodimension of the TOCSY spectrum. Similarly to the other two frequency dimensions, this one also resolves ambiguities and provides characteristic information. We show how the approach supports the analysis of a fragment of protein Tau Repeat-4 domain. Yet, its potential applications are far broader, including the analysis of complex mixtures or other polymers.
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Affiliation(s)
- Dariusz Gołowicz
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland
| | - Alexandra Shchukina
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
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5
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Nawrocka EK, Urbańczyk M, Koziński K, Kazimierczuk K. Variable-temperature NMR spectroscopy for metabolite identification in biological materials. RSC Adv 2021; 11:35321-35325. [PMID: 35493175 PMCID: PMC9043013 DOI: 10.1039/d1ra05626c] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/21/2021] [Indexed: 01/28/2023] Open
Abstract
Nuclear magnetic resonance is a "workhorse technique" used in metabolomics, complementary to mass spectrometry. Unfortunately, only the most basic NMR methods are sensitive enough to allow fast medical screening. The most common of them, a simple 1H NMR, suffers from low dispersion of resonance frequencies, which often hampers the identification of metabolites. In this article we show that 1H NMR spectra contain previously overlooked parameters potentially helpful in metabolite identification, namely the rates of temperature-induced changes of chemical shifts. We prove that they are reproducible between various metabolite mixtures and can be determined quickly when Radon transform is used to process the data.
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Affiliation(s)
- Ewa K Nawrocka
- Centre of New Technologies, University of Warsaw ul. Banacha 2C 02-097 Warsaw Poland
- Faculty of Chemistry, University of Warsaw ul. Pasteura 1 02-093 Warsaw Poland
| | - Mateusz Urbańczyk
- Centre of New Technologies, University of Warsaw ul. Banacha 2C 02-097 Warsaw Poland
- Institute of Physical Chemistry, Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
| | - Kamil Koziński
- Centre of New Technologies, University of Warsaw ul. Banacha 2C 02-097 Warsaw Poland
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6
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Gołowicz D, Kaźmierczak M, Kazimierczuk K. Benefits of time-resolved nonuniform sampling in reaction monitoring: The case of aza-Michael addition of benzylamine and acrylamide. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:213-220. [PMID: 33016346 DOI: 10.1002/mrc.5105] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/01/2020] [Accepted: 10/01/2020] [Indexed: 06/11/2023]
Abstract
Monitoring of chemical reactions is best carried out using methods that sample the test object at a rate greater than the time scale of the processes taking place. The recently proposed time-resolved nonuniform sampling (TR-NUS) method allows the use of two-dimensional (2D) nuclear magnetic resonance (NMR) spectra for this purpose and provides a time resolution equivalent to that achievable using one-dimensional spectra. Herein, we show that TR-NUS acquired data eliminates 2D spectral line disturbances and enables more accurate signal integration and kinetics conclusions. The considerations are exemplified with a seemingly simple aza-Michael reaction of benzylamine and acrylamide. Surprisingly, the product identification is possible only using 2D spectra, although credible monitoring requires TR-NUS.
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Affiliation(s)
- Dariusz Gołowicz
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Faculty of Chemistry, University of Warsaw, Warsaw, Poland
| | - Magdalena Kaźmierczak
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Faculty of Chemistry, Warsaw University of Technology, Warsaw, Poland
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7
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Chen J, Zeng Q, Tian D, Lin Y, Chen Z. High-resolution 2-D NMR spectroscopy based on the Radon transform and pure shift technique for studying chemical shifts perturbations. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2021; 59:346-353. [PMID: 31967670 DOI: 10.1002/mrc.5000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 01/11/2020] [Accepted: 01/19/2020] [Indexed: 06/10/2023]
Abstract
Chemical shift plays an important role in molecular analysis. However, chemical shifts are influenced by temperature, solvent concentration, pressure, and so forth. Therefore, measuring chemical shift perturbations caused by these factors is helpful to molecular studies. A new form of 2-D spectroscopy (projection spectroscopy) has been introduced whose indirect dimension is derived by implementing the Radon transform on a series of conventional 1-D proton spectra and indicates such perturbations. However, signal overlap may exist in the conventional 1-D spectra and hence in the resulting projection spectra, hampering clear multiplet analysis and accurate extraction of perturbations. Here, the pure shift decoupling technique is employed to obtain clearer projection spectrum with higher spectral resolution. The combination of pure shift technique and the Radon transform is helpful to accurately extract chemical shift perturbations. It is believed that this application will open up a vast prospect for molecular analysis.
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Affiliation(s)
- Jinyong Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China
| | - Qing Zeng
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China
| | - Dan Tian
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China
| | - Yanqin Lin
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China
- Shenzhen Research Institute of Xiamen University, Shenzhen, China
| | - Zhong Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China
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8
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Shchukina A, Małecki P, Mateos B, Nowakowski M, Urbańczyk M, Kontaxis G, Kasprzak P, Conrad-Billroth C, Konrat R, Kazimierczuk K. Temperature as an Extra Dimension in Multidimensional Protein NMR Spectroscopy. Chemistry 2021; 27:1753-1767. [PMID: 32985764 DOI: 10.1002/chem.202003678] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Indexed: 11/07/2022]
Abstract
NMR spectroscopy is a particularly informative method for studying protein structures and dynamics in solution; however, it is also one of the most time-consuming. Modern approaches to biomolecular NMR spectroscopy are based on lengthy multidimensional experiments, the duration of which grows exponentially with the number of dimensions. The experimental time may even be several days in the case of 3D and 4D spectra. Moreover, the experiment often has to be repeated under several different conditions, for example, to measure the temperature-dependent effects in a spectrum (temperature coefficients (TCs)). Herein, a new approach that involves joint sampling of indirect evolution times and temperature is proposed. This allows TCs to be measured through 3D spectra in even less time than that needed to acquire a single spectrum by using the conventional approach. Two signal processing methods that are complementary, in terms of sensitivity and resolution, 1) dividing data into overlapping subsets followed by compressed sensing reconstruction, and 2) treating the complete data set with a variant of the Radon transform, are proposed. The temperature-swept 3D HNCO spectra of two intrinsically disordered proteins, osteopontin and CD44 cytoplasmic tail, show that this new approach makes it possible to determine TCs and their non-linearities effectively. Non-linearities, which indicate the presence of a compact state, are particularly interesting. The complete package of data acquisition and processing software for this new approach are provided.
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Affiliation(s)
- Alexandra Shchukina
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Paweł Małecki
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097, Warsaw, Poland
| | - Borja Mateos
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Michał Nowakowski
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Mateusz Urbańczyk
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097, Warsaw, Poland
| | - Georg Kontaxis
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Paweł Kasprzak
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097, Warsaw, Poland.,Department of Mathematical Methods in Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Clara Conrad-Billroth
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter Campus 5, 1030, Vienna, Austria
| | - Robert Konrat
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, Vienna Biocenter Campus 5, 1030, Vienna, Austria
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9
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Gołowicz D, Kasprzak P, Orekhov V, Kazimierczuk K. Fast time-resolved NMR with non-uniform sampling. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2020; 116:40-55. [PMID: 32130958 DOI: 10.1016/j.pnmrs.2019.09.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 06/10/2023]
Abstract
NMR spectroscopy is a versatile tool for studying time-dependent processes: chemical reactions, phase transitions or macromolecular structure changes. However, time-resolved NMR is usually based on the simplest among available techniques - one-dimensional spectra serving as "snapshots" of the studied process. One of the reasons is that multidimensional experiments are very time-expensive due to costly sampling of evolution time space. In this review we summarize efforts to alleviate the problem of limited applicability of multidimensional NMR in time-resolved studies. We focus on techniques based on sparse or non-uniform sampling (NUS), which lead to experimental time reduction by omitting a significant part of the data during measurement and reconstructing it mathematically, adopting certain assumptions about the spectrum. NUS spectra are faster to acquire than conventional ones and thus better suited to the role of "snapshots", but still suffer from non-stationarity of the signal i.e. amplitude and frequency variations within a dataset. We discuss in detail how these instabilities affect the spectra, and what are the optimal ways of sampling the non-stationary FID signal. Finally, we discuss related areas of NMR where serial experiments are exploited and how they can benefit from the same NUS-based approaches.
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Affiliation(s)
- Dariusz Gołowicz
- Centre of New Technologies, University of Warsaw, Banacha 2C, Warsaw 02-097, Poland; Faculty of Chemistry, University of Warsaw, Pasteura 1, Warsaw 02-093, Poland.
| | - Paweł Kasprzak
- Centre of New Technologies, University of Warsaw, Banacha 2C, Warsaw 02-097, Poland; Department of Mathematical Methods in Physics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland.
| | - Vladislav Orekhov
- Department of Chemistry & Molecular Biology, University of Gothenburg, Box 462, 405 30 Gothenburg, Sweden.
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10
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Nawrocka EK, Kasprzak P, Zawada K, Sadło J, Grochala W, Kazimierczuk K, Leszczyński PJ. Nonstationary Two-Dimensional Nuclear Magnetic Resonance: A Method for Studying Reaction Mechanisms in Situ. Anal Chem 2019; 91:11306-11315. [PMID: 31387347 DOI: 10.1021/acs.analchem.9b02414] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nuclear magnetic resonance spectroscopy (NMR) is a versatile tool of chemical analysis allowing one to determine structures of molecules with atomic resolution. Particularly informative are two-dimensional (2D) experiments that directly identify atoms coupled by chemical bonds or a through-space interaction. Thus, NMR could potentially be powerful tool to study reactions in situ and explain their mechanisms. Unfortunately, 2D NMR is very time-consuming and thus often cannot serve as a "snapshot" technique for in situ reaction monitoring. Particularly difficult is the case of spectra, in which resonance frequencies vary in the course of reaction. This leads to resolution and sensitivity loss, often hindering the detection of transient products. In this paper we introduce a novel approach to correct such nonstationary 2D NMR signals and raise the detection limits over 10 times. We demonstrate success of its application for studying the mechanism of the reaction of AgSO4-induced synthesis of diphenylmethane-type compounds. Several reactions occur in the studied mixture of benzene and toluene, all with rather low yield and leading to compounds with similar chemical shifts. Nevertheless, with the use of a proposed 2D NMR approach we were able to describe complex mechanisms of diphenylmethane formation involving AgSO4-induced toluene deprotonation and formation of benzyl carbocation, followed by nucleophilic attacks.
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Affiliation(s)
- Ewa Klaudia Nawrocka
- Faculty of Chemistry , University of Warsaw , Pasteura 1 , 02-089 Warsaw , Poland.,Centre of New Technologies , University of Warsaw , Banacha 2C , 02-097 Warsaw , Poland
| | - Paweł Kasprzak
- Centre of New Technologies , University of Warsaw , Banacha 2C , 02-097 Warsaw , Poland.,Department of Mathematical Methods in Physics, Faculty of Physics , University of Warsaw , Pasteura 5 , 02-093 Warsaw , Poland
| | - Katarzyna Zawada
- Department of Physical Chemistry, Faculty of Pharmacy with the Laboratory Medicine Division , Medical University of Warsaw , Banacha 1 , 02-097 Warsaw , Poland
| | - Jarosław Sadło
- Institute of Nuclear Chemistry and Technology , Dorodna 16 , 03-195 Warsaw , Poland
| | - Wojciech Grochala
- Centre of New Technologies , University of Warsaw , Banacha 2C , 02-097 Warsaw , Poland
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11
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Rytel M, Kasprzak P, Setny P, Kazimierczuk K. Quick temperature-sweep pure-shift NMR: the case of solvent effects in atorvastatin. Phys Chem Chem Phys 2019; 21:19209-19215. [DOI: 10.1039/c9cp03921j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Quick and sensitive serial pseudo-2D pure-shift NMR experiments provide novel insight into the temperature-dependent solvent distribution.
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Affiliation(s)
- Małgorzata Rytel
- Centre of New Technologies
- University of Warsaw
- 02-097 Warsaw
- Poland
| | - Paweł Kasprzak
- Centre of New Technologies
- University of Warsaw
- 02-097 Warsaw
- Poland
- Department of Mathematical Methods in Physics
| | - Piotr Setny
- Centre of New Technologies
- University of Warsaw
- 02-097 Warsaw
- Poland
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12
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Urbańczyk M, Shchukina A, Gołowicz D, Kazimierczuk K. TReNDS-Software for reaction monitoring with time-resolved non-uniform sampling. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2019; 57:4-12. [PMID: 30255516 DOI: 10.1002/mrc.4796] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 09/10/2018] [Accepted: 09/11/2018] [Indexed: 06/08/2023]
Abstract
NMR spectroscopy, used routinely for structure elucidation, has also become a widely applied tool for process and reaction monitoring. However, the most informative of NMR methods-correlation experiments-are often useless in this kind of applications. The traditional sampling of a multidimensional FID is usually time-consuming, and thus, the reaction-monitoring toolbox was practically limited to 1D experiments (with rare exceptions, e.g., single-scan or fast-sampling experiments). Recently, the technique of time-resolved non-uniform sampling (TR-NUS) has been proposed, which allows to use standard multidimensional pulse sequences preserving the temporal resolution close to that achievable in 1D experiments. However, the method existed only as a prototype and did not allow on-the-fly processing during the reaction. In this paper, we introduce TReNDS: free, user-friendly software kit for acquisition and processing of TR-NUS data. The program works on Bruker, Agilent, and Magritek spectrometers, allowing to carry out up to four experiments with interleaved TR-NUS. The performance of the program is demonstrated on the example of enzymatic hydrolysis of sucrose.
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Affiliation(s)
- Mateusz Urbańczyk
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Spektrino Sp. z o.o., Warsaw, Poland
- NMR Research Unit, University of Oulu, Oulu, Finland
| | | | - Dariusz Gołowicz
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
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