1
|
Senthil Kumar HK, Noh Y, Bachmann AL, Beckingham BS. Compositional analysis of multilayered plastic constituents and constituent mixtures using benchtop 1H NMR spectroscopy. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:619-628. [PMID: 38693688 DOI: 10.1002/mrc.5450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 04/09/2024] [Accepted: 04/13/2024] [Indexed: 05/03/2024]
Abstract
Multilayered plastics are widely used in food packaging and other commercial applications due to their tailored functional properties. By layering different polymers, the multilayered composite material can have enhanced mechanical, thermal, and barrier properties compared to a single plastic. However, there is a significant need to recycle these multilayer plastics, but their complex structure offers significant challenges to their successful recycling. Ultimately, the use and recycling of these complex materials requires the ability to characterize the composition and purity as a means of quality control for both production and recycling processes. New advances and availability of low-field benchtop 1H NMR spectrometers have led to increasing interest in its use for characterization of multicomponent polymers and polymer mixtures. Here, we demonstrate the capability of low-field benchtop 1H NMR spectroscopy for characterization of three common polymers associated with multilayered packaging systems (low-density polyethylene [LDPE], ethylene vinyl alcohol [EVOH], and Nylon) as well as their blends. Calibration curves are obtained for determining the unknown composition of EVOH and Nylon in multilayered packaging plastics using both the EVOH hydroxyl peak area and an observed peak shift, both yielding results in good agreement with the prepared sample compositions. Additionally, comparison of results extracted for the same samples characterized by our benchtop spectrometer and a 500-MHz spectrometer found results to be consistent and within 2 wt% on average. Overall, low-field benchtop 1H NMR spectroscopy is a reliable and accessible tool for characterization of these polymer systems.
Collapse
Affiliation(s)
| | - Yoorae Noh
- Department of Chemical Engineering, Auburn University, Auburn, Alabama, USA
| | - Adam L Bachmann
- Department of Chemical Engineering, Auburn University, Auburn, Alabama, USA
| | - Bryan S Beckingham
- Department of Chemical Engineering, Auburn University, Auburn, Alabama, USA
| |
Collapse
|
2
|
Silva Elipe MV, Ndukwe IE, Murray JI. Cryogen-free 400-MHz nuclear magnetic resonance spectrometer as a versatile tool for pharmaceutical process analytical technology. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:512-534. [PMID: 38369696 DOI: 10.1002/mrc.5434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 02/20/2024]
Abstract
The discovery of new ceramic materials containing Ba-La-Cu oxides in 1986 that exhibited superconducting properties at high temperatures in the range of 35 K or higher, recognized with the Nobel Prize in Physics in 1987, opened a new world of opportunities for nuclear magnetic resonance (NMRs) and magnetic resonance imaging (MRIs) to move away from liquid cryogens. This discovery expands the application of high temperature superconducting (HTS) materials to fields beyond the chemical and medical industries, including electrical power grids, energy, and aerospace. The prototype 400-MHz cryofree HTS NMR spectrometer installed at Amgen's chemistry laboratory has been vital for a variety of applications such as structure analysis, reaction monitoring, and CASE-3D studies with RDCs. The spectrometer has been integrated with Amgen's chemistry and analytical workflows, providing pipeline project support in tandem with other Kinetic Analysis Platform technologies. The 400-MHz cryofree HTS NMR spectrometer, as the name implies, does not require liquid cryogens refills and has smaller footprint that facilitates installation into a chemistry laboratory fume hood, sharing the hood with a process chemistry reactor. Our evaluation of its performance for structural analysis with CASE-3D protocol and for reaction monitoring of Amgen's pipeline chemistry was successful. We envision that the HTS magnets would become part of the standard NMR and MRI spectrometers in the future. We believe that while the technology is being developed, there is room for all magnet options, including HTS, low temperature superconducting (LTS) magnets, and low field benchtop NMRs with permanent magnets, where utilization will be dependent on application type and costs.
Collapse
Affiliation(s)
| | - Ikenna Edward Ndukwe
- Department of Attribute Sciences, Process Development, Amgen Inc., Thousand Oaks, California, USA
| | - James I Murray
- Pivotal and Commercial Drug Substance Technologies, Process Development, Amgen Inc., Thousand Oaks, California, USA
| |
Collapse
|
3
|
Le-McClain A, Zanelotti C, Robert H, Casanova F. Analysis of complex mixtures with benchtop nuclear magnetic resonance: Solvent suppression with T 2 and diffusion filters. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:497-504. [PMID: 38369688 DOI: 10.1002/mrc.5438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/22/2024] [Accepted: 01/24/2024] [Indexed: 02/20/2024]
Abstract
Benchtop nuclear magnetic resonance (NMR) spectrometers are being employed in a wide variety of applications from undergraduate teaching and research in academia to quality control and process monitoring in industrial settings. Incorporating benchtop NMR in some of these applications presents opportunities for new practical uses of the technology and challenges that truly test the capabilities of compact NMR spectrometers. For instance, the use of protonated solvents in manufacturing or process monitoring requires separating and quantitating the analyte signals of interest from the strong (overwhelming) response from the solvents. Furthermore, due to the lower field strength available with permanent magnet spectrometers, the NMR spectra of complex mixtures can be more difficult to analyze due to partial or complete signal overlap. To address some of these challenges and to extend the range of applications of benchtop NMR, we investigate NMR techniques that enable quantitative analysis of different components in mixtures. These pulse sequences can be used to suppress one or multiple solvent peaks, to filter out signals by spin-spin relaxation time (T2), or to separate signal components by a molecule's diffusion coefficient (NMR diffusometry). In this paper, we discuss quantitative analysis of excipients in buffers for therapeutic proteins to highlight the usefulness of these NMR pulse sequences in the analysis of complex samples with benchtop NMR spectrometers.
Collapse
|
4
|
Jenne A, Soong R, Downey K, Biswas RG, Decker V, Busse F, Goerling B, Haber A, Simpson MJ, Simpson AJ. Brewing alcohol 101: An undergraduate experiment utilizing benchtop NMR for quantification and process monitoring. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:429-438. [PMID: 38230451 DOI: 10.1002/mrc.5428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 12/22/2023] [Accepted: 01/01/2024] [Indexed: 01/18/2024]
Abstract
In recent years there has been a renewed interest in benchtop NMR. Given their lower cost of ownership, smaller footprint, and ease of use, they are especially suited as an educational tool. Here, a new experiment targeted at upper-year undergraduates and first-year graduate students follows the conversion of D-glucose into ethanol at low-field. First, high and low-field data on D-glucose are compared and students learn both the Hz and ppm scales and how J-coupling is field-independent. The students then acquire their own quantitative NMR datasets and perform the quantification using an Electronic Reference To Access In Vivo Concentration (ERETIC) technique. To our knowledge ERETIC is not currently taught at the undergraduate level, but has an advantage in that internal standards are not required; ideal for following processes or with future use in flow-based benchtop monitoring. Using this quantitative data, students can relate a simple chemical process (fermentation) back to more complex topics such as reaction kinetics, bridging the gaps between analytical and physical chemistry. When asked to reflect on the experiment, students had an overwhelmingly positive experience, citing agreement with learning objectives, ease of understanding the protocol, and enjoyment. Each of the respondents recommended this experiment as a learning tool for others. This experiment has been outlined for other instructors to utilize in their own courses across institutions, with the hope that a continued expansion of low-field NMR will increase accessibility and learning opportunities at the undergraduate level.
Collapse
Affiliation(s)
- Amy Jenne
- Environmental NMR Center, University of Toronto Scarborough, Toronto, ON, Canada
| | - Ronald Soong
- Environmental NMR Center, University of Toronto Scarborough, Toronto, ON, Canada
| | - Katelyn Downey
- Environmental NMR Center, University of Toronto Scarborough, Toronto, ON, Canada
| | | | | | | | | | | | - Myrna J Simpson
- Environmental NMR Center, University of Toronto Scarborough, Toronto, ON, Canada
| | - Andre J Simpson
- Environmental NMR Center, University of Toronto Scarborough, Toronto, ON, Canada
| |
Collapse
|
5
|
Pellizzari J, Soong R, Downey K, Biswas RG, Kock FC, Steiner K, Goerling B, Haber A, Decker V, Busse F, Simpson M, Simpson A. Slice through the water-Exploring the fundamental challenge of water suppression for benchtop NMR systems. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:463-473. [PMID: 38282484 DOI: 10.1002/mrc.5431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 12/01/2023] [Accepted: 01/02/2024] [Indexed: 01/30/2024]
Abstract
Benchtop NMR provides improved accessibility in terms of cost, space, and technical expertise. In turn, this encourages new users into the field of NMR spectroscopy. Unfortunately, many interesting samples in education and research, from beer to whole blood, contain significant amounts of water that require suppression in 1H NMR in order to recover sample information. However, due to the significant reduction in chemical shift dispersion in benchtop NMR systems, the sample signals are much closer to the water resonance compared to those in a corresponding high-field NMR spectrum. Therefore, simply translating solvent suppression experiments intended for high-field NMR instruments to benchtop NMR systems without careful consideration can be problematic. In this study, the effectiveness of several popular water suppression schemes was evaluated for benchtop NMR applications. Emphasis is placed on pulse sequences with no, or few, adjustable parameters making them easy to implement. These fall into two main categories: (1) those based on Pre-SAT including Pre-SAT, PURGE, NOESY-PR, and g-NOESY-PR and (2) those based on binomial inversion including JRS and W5-WATERGATE. Among these schemes, solvent suppression sequences based on Pre-SAT offer a general approach for easy solvent suppression for samples with higher analyte concentrations (sucrose standard and Redbull™). However, for human urine, binomial-like sequences were required. In summary, it is demonstrated that highly efficient water suppression approaches can be implemented on benchtop NMR systems in a simple manner, despite the limited spectral dispersion, further illustrating the potential for widespread implementation of these approaches in education and research.
Collapse
Affiliation(s)
| | - Ronald Soong
- University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Katelyn Downey
- University of Toronto Scarborough, Toronto, Ontario, Canada
| | | | - Flavio C Kock
- University of Toronto Scarborough, Toronto, Ontario, Canada
| | | | | | | | | | | | - Myrna Simpson
- University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Andre Simpson
- University of Toronto Scarborough, Toronto, Ontario, Canada
| |
Collapse
|
6
|
Remy C, Danoun S, Delample M, Morris C, Gilard V, Balayssac S. Characterization of fatty acid forms using benchtop NMR in omega-3 oil supplements. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:328-336. [PMID: 37736944 DOI: 10.1002/mrc.5398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/08/2023] [Accepted: 09/11/2023] [Indexed: 09/23/2023]
Abstract
Omega-3 fatty acid supplements, such as fish oil and plant-based oils, have gained popularity because of their potential health benefits. However, the quality and composition of these supplements can vary widely, particularly in terms of the two main forms of omega-3 fatty acids: triacylglycerols (TAGs) and ethyl esters (EEs). TAGs are the natural form found in fish oil but are prone to oxidation, whereas EEs are more stable but less well absorbed by the body. Differentiating between these forms is crucial for assessing the efficacy and tolerance of omega-3 supplements. This article describes a novel approach to differentiate between TAG and EE forms of omega-3 fatty acids in dietary supplements, utilizing a 60-MHz benchtop nuclear magnetic resonance (NMR) spectrometer. The proposed method using 1H and 1H-1H COSY NMR provides a quick and accurate approach to screen the forms of omega-3 fatty acids and evaluate their ratios. The presence of diacylglycerol (DAGs) in some supplements was also highlighted by this method and adds some information about the process used (i.e., esterification/enrichment). The affordability and user-friendliness of benchtop NMR equipment make this method feasible for food processing companies or quality control laboratories. In this study, 24 oil supplements were analyzed using NMR analysis in order to demonstrate the potential of this method for the differentiation of TAG and EE forms in omega-3 supplements.
Collapse
Affiliation(s)
- Carla Remy
- Laboratoire des IMRCP, Université de Toulouse, CNRS UMR 5623, Université Toulouse III-Paul Sabatier, Toulouse Cedex, France
| | - Saïda Danoun
- Laboratoire SPCMIB, Université de Toulouse, CNRS UMR 5068, Université Toulouse III-Paul Sabatier, Toulouse Cedex, France
| | | | | | - Véronique Gilard
- Laboratoire des IMRCP, Université de Toulouse, CNRS UMR 5623, Université Toulouse III-Paul Sabatier, Toulouse Cedex, France
| | - Stéphane Balayssac
- Laboratoire des IMRCP, Université de Toulouse, CNRS UMR 5623, Université Toulouse III-Paul Sabatier, Toulouse Cedex, France
| |
Collapse
|
7
|
Phuong J, Romero Z, Hasse H, Münnemann K. Polarization transfer methods for quantitative analysis of flowing mixtures with benchtop 13C NMR spectroscopy. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:398-411. [PMID: 38114253 DOI: 10.1002/mrc.5417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 11/06/2023] [Accepted: 11/09/2023] [Indexed: 12/21/2023]
Abstract
Benchtop NMR spectroscopy is attractive for process monitoring; however, there are still drawbacks that often hamper its use, namely, the comparatively low spectral resolution in 1H NMR, as well as the low signal intensities and problems with the premagnetization of flowing samples in 13C NMR. We show here that all these problems can be overcome by using 1H-13C polarization transfer methods. Two ternary test mixtures (one with overlapping peaks in the 1H NMR spectrum and one with well-separated peaks, which was used as a reference) were studied with a 1 T benchtop NMR spectrometer using the polarization transfer sequence PENDANT (polarization enhancement that is nurtured during attached nucleus testing). The mixtures were analyzed quantitatively in stationary as well as in flow experiments by PENDANT enhanced 13C NMR experiments, and the results were compared with those from the gravimetric sample preparation and from standard 1H and 13C NMR spectroscopy. Furthermore, as a proxy for a process monitoring application, continuous dilution experiments were carried out, and the composition of the mixture was monitored in a flow setup by 13C NMR benchtop spectroscopy with PENDANT. The results demonstrate the high potential of polarization transfer methods for applications in quantitative process analysis with benchtop NMR instruments, in particular with flowing samples.
Collapse
Affiliation(s)
- Johnnie Phuong
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
- Laboratory of Advanced Spin Engineering - Magnetic Resonance (LASE-MR), RPTU Kaiserslautern, Kaiserslautern, Germany
| | - Zeno Romero
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
- Laboratory of Advanced Spin Engineering - Magnetic Resonance (LASE-MR), RPTU Kaiserslautern, Kaiserslautern, Germany
| | - Hans Hasse
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
- Laboratory of Advanced Spin Engineering - Magnetic Resonance (LASE-MR), RPTU Kaiserslautern, Kaiserslautern, Germany
| | - Kerstin Münnemann
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
- Laboratory of Advanced Spin Engineering - Magnetic Resonance (LASE-MR), RPTU Kaiserslautern, Kaiserslautern, Germany
| |
Collapse
|
8
|
Phuong J, Mross S, Bellaire D, Hasse H, Münnemann K. Determination of self-diffusion coefficients in mixtures with benchtop 13C NMR spectroscopy via polarization transfer. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:386-397. [PMID: 38014888 DOI: 10.1002/mrc.5412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 10/18/2023] [Accepted: 10/25/2023] [Indexed: 11/29/2023]
Abstract
Nuclear magnetic resonance (NMR) is an established method to determine self-diffusion coefficients in liquids with high precision. The development of benchtop NMR spectrometers makes the method accessible to a wider community. In most cases, 1H NMR spectroscopy is used to determine self-diffusion coefficients due to its high sensitivity. However, especially when using benchtop NMR spectrometers for the investigation of complex mixtures, the signals in 1H NMR spectra can overlap, hindering the precise determination of self-diffusion coefficients. In 13C NMR spectroscopy, the signals of different compounds are generally well resolved. However, the sensitivity of 13C NMR is significantly lower than that of 1H NMR spectroscopy leading to very long measurement times, which makes diffusion coefficient measurements based on 13C NMR practically infeasible with benchtop NMR spectrometers. To circumvent this problem, we have combined two known pulse sequences, one for polarization transfer from 1H to the 13C nuclei (PENDANT) and one for the measurement of diffusion coefficients (PFG). The new method (PENPFG) was used to measure the self-diffusion coefficients of three pure solvents (acetonitrile, ethanol and 1-propanol) as well as in all their binary mixtures and the ternary mixture at various compositions. For comparison, also measurements of the same systems were carried out with a standard PFG-NMR routine on a high-field NMR instrument. The results are in good agreement and show that PENPFG is a useful tool for the measurement of the absolute value of the self-diffusion coefficients in complex liquid mixtures with benchtop NMR spectrometers.
Collapse
Affiliation(s)
- Johnnie Phuong
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
| | - Sarah Mross
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
| | - Daniel Bellaire
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
| | - Hans Hasse
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
| | - Kerstin Münnemann
- Laboratory of Engineering Thermodynamics (LTD), RPTU Kaiserslautern, Kaiserslautern, Germany
| |
Collapse
|
9
|
Kemsley EK. Graphical exploration of 600- and 60-MHz proton NMR spectral datasets from ground roast coffee extracts. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:236-251. [PMID: 37311710 DOI: 10.1002/mrc.5373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 05/24/2023] [Accepted: 05/30/2023] [Indexed: 06/15/2023]
Abstract
This article uses a variety of graphical and mathematical approaches to analyse 600- and 60-MHz ('benchtop') proton NMR spectra acquired from lipophilic and hydrophilic extracts of roasted coffee beans. The collection of 40 authenticated samples comprised various coffee species, cultivars and hybrids. The spectral datasets were analysed by a combination of metabolomics approaches, cross-correlation and whole spectrum methods, assisted by visualisation and mathematical techniques not conventionally employed to treat NMR data. A large amount of information content was shared between the 600-MHz and benchtop datasets, including in its magnitude spectral form, suggesting the potential for a lower cost, lower tech route to conducting informative metabolomics studies.
Collapse
Affiliation(s)
- E Kate Kemsley
- Core Science Resources Group, Quadram Institute Bioscience, Norwich, UK
| |
Collapse
|
10
|
Bornemann-Pfeiffer M, Meyer K, Lademann J, Kraume M, Maiwald M. Contributions towards variable temperature shielding for compact NMR instruments. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:259-268. [PMID: 37438985 DOI: 10.1002/mrc.5379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 06/23/2023] [Accepted: 06/28/2023] [Indexed: 07/14/2023]
Abstract
The application of compact NMR instruments to hot flowing samples or exothermically reacting mixtures is limited by the temperature sensitivity of permanent magnets. Typically, such temperature effects directly influence the achievable magnetic field homogeneity and hence measurement quality. The internal-temperature control loop of the magnet and instruments is not designed for such temperature compensation. Passive insulation is restricted by the small dimensions within the magnet borehole. Here, we present a design approach for active heat shielding with the aim of variable temperature control of NMR samples for benchtop NMR instruments using a compressed airstream which is variable in flow and temperature. Based on the system identification and surface temperature measurements through thermography, a model predictive control was set up to minimise any disturbance effect on the permanent magnet from the probe or sample temperature. This methodology will facilitate the application of variable-temperature shielding and, therefore, extend the application of compact NMR instruments to flowing sample temperatures that differ from the magnet temperature.
Collapse
Affiliation(s)
- Martin Bornemann-Pfeiffer
- Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany
- Chair of Chemical and Process Engineering, Technical University Berlin, Berlin, Germany
| | - Klas Meyer
- Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany
| | - Jeremy Lademann
- Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany
| | - Matthias Kraume
- Chair of Chemical and Process Engineering, Technical University Berlin, Berlin, Germany
| | - Michael Maiwald
- Bundesanstalt für Materialforschung und -prüfung, Berlin, Germany
| |
Collapse
|
11
|
Kircher R, Xu J, Barskiy DA. In Situ Hyperpolarization Enables 15N and 13C Benchtop NMR at Natural Isotopic Abundance. J Am Chem Soc 2024; 146:514-520. [PMID: 38126275 DOI: 10.1021/jacs.3c10030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Without employing isotopic labeling, we demonstrate the generation of 15N and 13C NMR signals for molecules containing -NH2 motifs using benchtop NMR spectrometers (1-1.4 T). Specifically, high-SNR (>50) detection of ammonia, 4-aminopyridine, benzylamine, and phenethylamine dissolved in methanol or dichloromethane is demonstrated after only 10 s of parahydrogen bubbling using signal amplification by reversible exchange and applying a pulse sequence based on spin-lock-induced crossing. Optimization of the sequence parameters allows us to achieve up to 12% 15N and 0.4% 13C polarization in situ without the need for the sample transfer typically employed in other hyperpolarization methods. Moreover, hyperpolarization is generated continuously without having to stop the parahydrogen bubbling to reset magnetization, paving the way toward fast 2D spectroscopic methods and relaxometry. The provided methodology may find application for the identification of diluted chemicals relevant to industry and research with the aid of affordable benchtop NMR spectrometers.
Collapse
Affiliation(s)
- Raphael Kircher
- Johannes Gutenberg Universität Mainz, 55128, Mainz, Germany
- Helmholtz-Institut Mainz, 55128, Mainz, Germany
- Helmholtzzentrum für Schwerionenforschung, 64291, Darmstadt, Germany
| | - Jingyan Xu
- Johannes Gutenberg Universität Mainz, 55128, Mainz, Germany
- Helmholtz-Institut Mainz, 55128, Mainz, Germany
- Helmholtzzentrum für Schwerionenforschung, 64291, Darmstadt, Germany
| | - Danila A Barskiy
- Johannes Gutenberg Universität Mainz, 55128, Mainz, Germany
- Helmholtz-Institut Mainz, 55128, Mainz, Germany
- Helmholtzzentrum für Schwerionenforschung, 64291, Darmstadt, Germany
| |
Collapse
|
12
|
Yang L, Chen F, Chen L, Zhang Z, Chen J, Wang J, Cheng X, Feng J, Bao Q, Liu C. An easy-built Halbach magnet for LF-NMR with high homogeneity using optimized target-field passive shimming method. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 357:107582. [PMID: 37950959 DOI: 10.1016/j.jmr.2023.107582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 10/01/2023] [Accepted: 10/30/2023] [Indexed: 11/13/2023]
Abstract
The aim of this work is to develop a Halbach magnet that possesses characteristics such as easy-built, low cost and high homogeneity for use in a portable low-field NMR (LF-NMR) system. Considering portability, a 4-ring Halbach magnet was designed through simulation and mechanical modelling, which was successfully constructed in a general laboratory setting. The obtained field strength (B0) was 0.169 T, with an initial homogeneity of 8204 ppm within a sphere with a diameter of 20 mm. To enhance robustness, efficiency and effectiveness of shimming, an optimized target-field passive shimming method was proposed. Subsequently, the homemade spectrometer was used to run NMR experiments on the Halbach magnet. The 1H NMR linewidths of water samples became significantly narrower after passive shimming, e.g., the linewidth of a sample with a diameter of 3 mm and a length of 3 mm reduced from 452.3 Hz (62.5 ppm) to 12.9 Hz (1.8 ppm), which was much less than 102 Hz. The NMR results demonstrate that the proposed passive shimming method can achieve high homogeneity, and the developed Halbach magnet is capable of satisfying numerous LF-NMR applications.
Collapse
Affiliation(s)
- Lize Yang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fang Chen
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Li Chen
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junfei Chen
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiaxin Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Cheng
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiwen Feng
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingjia Bao
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chaoyang Liu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China; Optics Valley Laboratory, Wuhan 430074, China.
| |
Collapse
|
13
|
Galvan D, de Aguiar LM, Bona E, Marini F, Killner MHM. Successful combination of benchtop nuclear magnetic resonance spectroscopy and chemometric tools: A review. Anal Chim Acta 2023; 1273:341495. [PMID: 37423658 DOI: 10.1016/j.aca.2023.341495] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/20/2023] [Accepted: 06/05/2023] [Indexed: 07/11/2023]
Abstract
Low-field nuclear magnetic resonance (NMR) has three general modalities: spectroscopy, imaging, and relaxometry. In the last twelve years, the modality of spectroscopy, also known as benchtop NMR, compact NMR, or just low-field NMR, has undergone instrumental development due to new permanent magnetic materials and design. As a result, benchtop NMR has emerged as a powerful analytical tool for use in process analytical control (PAC). Nevertheless, the successful application of NMR devices as an analytical tool in several areas is intrinsically linked to its coupling with different chemometric methods. This review focuses on the evolution of benchtop NMR and chemometrics in chemical analysis, including applications in fuels, foods, pharmaceuticals, biochemicals, drugs, metabolomics, and polymers. The review also presents different low-resolution NMR methods for spectrum acquisition and chemometric techniques for calibration, classification, discrimination, data fusion, calibration transfer, multi-block and multi-way.
Collapse
Affiliation(s)
- Diego Galvan
- Chemistry Institute, Universidade Federal de Mato Grosso do Sul (UFMS), 79070-900, Campo Grande, MS, Brazil; Chemistry Departament, Universidade Estadual de Londrina (UEL), 86.057-970, Londrina, PR, Brazil.
| | | | - Evandro Bona
- Post-Graduation Program of Food Technology (PPGTA), Universidade Tecnológica Federal do Paraná (UTFPR), Campus Campo Mourão, 87301-899, Campo Mourão, PR, Brazil; Post-Graduation Program of Chemistry (PPGQ), Universidade Tecnológica Federal do Paraná (UTFPR), Campus Curitiba, 80230-901, Curitiba, PR, Brazil
| | - Federico Marini
- Department of Chemistry, University of Rome "La Sapienza", Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Mário Henrique M Killner
- Chemistry Departament, Universidade Estadual de Londrina (UEL), 86.057-970, Londrina, PR, Brazil
| |
Collapse
|
14
|
Tang B, Chong K, Ragauskas AJ, Evans R. Quantitative Low-Field 19 F Nuclear Magnetic Resonance Analysis of Carbonyl Groups in Pyrolysis Oils. CHEMSUSCHEM 2023; 16:e202300625. [PMID: 37318880 DOI: 10.1002/cssc.202300625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 06/09/2023] [Accepted: 06/14/2023] [Indexed: 06/17/2023]
Abstract
Pyrolysis bio-oils, one of the products of lignocellulosic biomass pyrolysis, have the potential to be widely used as fuels. The chemical composition of bio-oils is very complicated as they contain hundreds, if not thousands, of different, mostly oxygen-containing, compounds with a wide distribution of physical properties, chemical structures, and concentrations. Detailed knowledge of bio-oil composition is crucial for optimizing both the pyrolysis processes and for any subsequent upgrading into a more viable fuel resource. Here we report the successful use of low-field, or benchtop, nuclear magnetic resonance (NMR) spectrometers in the analysis of pyrolysis oils. Pyrolysis oils from four different feedstocks were derivatized and analyzed using 19 F NMR techniques. The NMR results compare favorably with titrations for total carbonyl content. In addition, the benchtop NMR spectrometer proves able to reveal key spectral features, thus allowing the quantification of different carbonyl groups, such as aldehydes, ketones and quinones. Benchtop NMR spectrometers are typically compact, cheaper than their superconducting counterparts and do not require cryogens. Their use will make NMR analysis of pyrolysis oils easier and more accessible to a wide range of different potential users.
Collapse
Affiliation(s)
- Bridget Tang
- Aston Institute of Materials Research, Aston University, Aston Triangle, Birmingham, B4 7ET, UK
| | - Katie Chong
- Energy and Bioproducts Research Institute, Aston University, Aston Triangle, Birmingham, B4 7ET, UK
| | - Arthur J Ragauskas
- Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, Tennessee, 37996, United States
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37771, United States
| | - Robert Evans
- Aston Institute of Materials Research, Aston University, Aston Triangle, Birmingham, B4 7ET, UK
| |
Collapse
|
15
|
Zhu H, Zhang XX, Zhang R, Feng JY, Thakur K, Zhang JG, Wei ZJ. Anti-hardening effect and mechanism of silkworm sericin peptide in high protein nutrition bars during early storage. Food Chem 2023; 407:135168. [PMID: 36508867 DOI: 10.1016/j.foodchem.2022.135168] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/28/2022] [Accepted: 12/05/2022] [Indexed: 12/14/2022]
Abstract
Hardening presents an inevitable challenge during the storage of high protein nutrition bars. Sericin peptide is the product of hydrolysis of sericin, a protein from the silkworm cocoon. Here in, the effects of sericin peptide addition on the hardening of high protein nutrition bars during 72 h of storage were investigated. The addition of sericin peptide to high protein nutrition bars reduced the hardening of the sample during the early storage, The main mechanism was to improve the mobility of water and small hydrophilic molecules, which slowed down the phase separation. As well, after sericin peptide addition, the ζ- potential, the content of secondary structure, and the surface hydrophobicity of the samples were also changed, which prevented the self-aggregation of proteins. These results indicate that SRP can be used as a promising anti-hardening ingredient in the food industry to improve the texture of food products.
Collapse
Affiliation(s)
- Hongtao Zhu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, People's Republic of China
| | - Xiu-Xiu Zhang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, People's Republic of China
| | - Rui Zhang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, People's Republic of China.
| | - Jing-Yu Feng
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, People's Republic of China
| | - Kiran Thakur
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, People's Republic of China; School of Biological Science and Engineering, Collaborative Innovation Center for Food Production and Safety, North Minzu University, Yinchuan 750021, People's Republic of China.
| | - Jian-Guo Zhang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, People's Republic of China; School of Biological Science and Engineering, Collaborative Innovation Center for Food Production and Safety, North Minzu University, Yinchuan 750021, People's Republic of China.
| | - Zhao-Jun Wei
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, People's Republic of China; School of Biological Science and Engineering, Collaborative Innovation Center for Food Production and Safety, North Minzu University, Yinchuan 750021, People's Republic of China.
| |
Collapse
|
16
|
Alonso-Moreno P, Rodriguez I, Izquierdo-Garcia JL. Benchtop NMR-Based Metabolomics: First Steps for Biomedical Application. Metabolites 2023; 13:metabo13050614. [PMID: 37233655 DOI: 10.3390/metabo13050614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 04/19/2023] [Accepted: 04/24/2023] [Indexed: 05/27/2023] Open
Abstract
Nuclear magnetic resonance (NMR)-based metabolomics is a valuable tool for identifying biomarkers and understanding the underlying metabolic changes associated with various diseases. However, the translation of metabolomics analysis to clinical practice has been limited by the high cost and large size of traditional high-resolution NMR spectrometers. Benchtop NMR, a compact and low-cost alternative, offers the potential to overcome these limitations and facilitate the wider use of NMR-based metabolomics in clinical settings. This review summarizes the current state of benchtop NMR for clinical applications where benchtop NMR has demonstrated the ability to reproducibly detect changes in metabolite levels associated with diseases such as type 2 diabetes and tuberculosis. Benchtop NMR has been used to identify metabolic biomarkers in a range of biofluids, including urine, blood plasma and saliva. However, further research is needed to optimize the use of benchtop NMR for clinical applications and to identify additional biomarkers that can be used to monitor and manage a range of diseases. Overall, benchtop NMR has the potential to revolutionize the way metabolomics is used in clinical practice, providing a more accessible and cost-effective way to study metabolism and identify biomarkers for disease diagnosis, prognosis, and treatment.
Collapse
Affiliation(s)
- Pilar Alonso-Moreno
- NMR and Imaging in Biomedicine Group, Instituto Pluridisciplinar, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Ignacio Rodriguez
- NMR and Imaging in Biomedicine Group, Instituto Pluridisciplinar, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Department of Chemistry in Pharmaceutical Sciences, Pharmacy School, Universidad Complutense de Madrid, 28040 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Jose Luis Izquierdo-Garcia
- NMR and Imaging in Biomedicine Group, Instituto Pluridisciplinar, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Department of Chemistry in Pharmaceutical Sciences, Pharmacy School, Universidad Complutense de Madrid, 28040 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain
| |
Collapse
|
17
|
Schmid E, Rondeau S, Rudszuck T, Nirschl H, Guthausen G. Inline NMR via a Dedicated V-Shaped Sensor. SENSORS (BASEL, SWITZERLAND) 2023; 23:2388. [PMID: 36904592 PMCID: PMC10007489 DOI: 10.3390/s23052388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 02/13/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
Process monitoring and control require dedicated and reliable measures which reflect the status of the process under investigation. Although nuclear magnetic resonance is known to be a versatile analytical technique, it is only seldomly found in process monitoring. Single-sided nuclear magnetic resonance is one well known approach for being applied in process monitoring. The dedicated V-sensor is a recent approach that allows the inline investigation of materials in a pipe non-destructively and non-invasively. An open geometry of the radiofrequency unit is realized using a tailored coil, enabling the sensor to be applied for manifold mobile applications in in-line process monitoring. Stationary liquids were measured, and their properties were integrally quantified as the basis for successful process monitoring. The sensor, in its inline version, is presented along with its characteristics. An exemplary field of application is battery production in terms of anode slurries; thus, the first results on graphite slurries will demonstrate the added value of the sensor in process monitoring.
Collapse
Affiliation(s)
- Eric Schmid
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Simon Rondeau
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Thomas Rudszuck
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Hermann Nirschl
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Gisela Guthausen
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
- Engler-Bunte-Institut, Chair of Water Chemistry and Water Technology, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| |
Collapse
|
18
|
Draper SL, McCarney ER. Benchtop nuclear magnetic resonance spectroscopy in forensic chemistry. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:106-129. [PMID: 34286862 DOI: 10.1002/mrc.5197] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/21/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a powerful technique well known for its ability to elucidate structures and analyse mixtures and its quantitative nature. However, the cost and maintenance of high field NMR instruments prevent its widespread use by forensic chemists. The introduction of benchtop NMR spectrometers to the market operating at 40-80 MHz have a small footprint, are easy to use and cost much less than high field instruments, which makes them well suited to meet the needs of forensic chemists. These modern low field spectrometers are often capable of running multiple nuclei including 1 H, 13 C, 19 F and 31 P; 2D NMR experiments and advanced experiments such as solvent suppression and diffusion-ordered spectroscopy (DOSY) are possible. This has resulted in a number of publications in the area of forensic chemistry using benchtop NMR spectroscopy in the last 5 years that was previously missing from the literature. This mini review summarises this research including examples of benchtop NMR being used to identify and quantify compounds relevant to forensics and some advanced methods that may be used to overcome some of the limitations of these instruments for forensic analysis. Further validation and automation are likely required for widespread uptake of benchtop NMR in industry; however, it has been demonstrated as a useful complement to other analytical techniques commonplace of forensic laboratories.
Collapse
Affiliation(s)
- Sarah L Draper
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand
| | | |
Collapse
|
19
|
Araneda JF, Baumgarte M, Lange M, Maier AFG, Riegel SD. Identification of seven psychedelic 2,5-dimethoxy-phenylethyl-amine-based designer drugs via benchtop 1 H nuclear magnetic resonance spectroscopy. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:66-72. [PMID: 34404110 DOI: 10.1002/mrc.5205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 08/10/2021] [Accepted: 08/12/2021] [Indexed: 06/13/2023]
Abstract
The dissemination of spectral information of new psychoactive substances (NPS) acquired on benchtop nuclear magnetic resonance (NMR) spectrometers is of high importance considering the emerging application of such portable and accessible instruments in forensic analyses. Seven members of the 2C-X series (2C-B, 2C-C, 2C-D, 2C-E, 2C-P, 2C-T2, and 2C-T7) of NPS were analyzed via 60 MHz 1 H benchtop NMR spectroscopy and their molecular structural relations are discussed with respect to the observed proton NMR spectra.
Collapse
Affiliation(s)
- Juan F Araneda
- Application Chemistry, Nanalysis Corp., Calgary, Alberta, Canada
| | - Marion Baumgarte
- Forensic Science Institute, State Criminal Police Office of Lower Saxony, Hanover, Germany
| | - Marie Lange
- Forensic Science Institute, State Criminal Police Office of Lower Saxony, Hanover, Germany
| | | | - Susanne D Riegel
- Application Chemistry, Nanalysis Corp., Calgary, Alberta, Canada
| |
Collapse
|
20
|
Osman A, Chittiboyina AG, Avula B, Ali Z, Adams SJ, Khan IA. Quality Consistency of Herbal Products: Chemical Evaluation. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2023; 122:163-219. [PMID: 37392312 DOI: 10.1007/978-3-031-26768-0_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/03/2023]
Abstract
The widespread utility of herbal products has been rising considerably worldwide, including both developed and developing countries, leading to the rapid growth of their availability in the United States and globally. This substantial increase in consumption of herbal products has witnessed the emergence of adverse effects upon oral administration of certain of these products, and thus has raised safety concerns. The adverse effects caused by the consumption of certain botanical medicines occur primarily as a result of the poor quality of plant raw materials or the finished products, which inherently may affect safety and/or efficacy. The poor quality of some herbal products can be attributed to a lack of proper quality assurance and quality control. A high demand for herbal products that surpasses production, combined with a desire for maximizing profits, along with a lack of rigorous quality control within some manufacturing facilities have led to the emergence of quality inconsistencies. The underlying causes for this involve the misidentification of plant species, or their substitution, adulteration, or contamination with harmful ingredients. Analytical assessments have revealed there to be frequent and significant compositional variations between marketed herbal products. The inconsistency of the quality of herbal products can be ascribed essentially to the inconsistency of the botanical raw material quality used to manufacture the products. Thus, the quality assurance and the quality control of the botanical raw materials is may contribute significantly to improving the quality and consistency of the quality of the end products. The current chapter focuses on the chemical evaluation of quality and consistency of herbal products, including botanical dietary supplements. Different techniques, instruments, applications, and methods used in identifying, quantifying, and generating chemical fingerprints and chemical profiles of the ingredients of the herbal products will be described. The strengths and weaknesses of the various techniques available will be addressed. Limitations of the other approaches including morphological or microscopic analysis and DNA-based analysis will be presented.
Collapse
Affiliation(s)
- Ahmed Osman
- School of Pharmacy, National Center for Natural Products Research, The University of Mississippi, University, MS, 38677, USA.
| | - Amar G Chittiboyina
- School of Pharmacy, National Center for Natural Products Research, The University of Mississippi, University, MS, 38677, USA
| | - Bharathi Avula
- School of Pharmacy, National Center for Natural Products Research, The University of Mississippi, University, MS, 38677, USA
| | - Zulfiqar Ali
- School of Pharmacy, National Center for Natural Products Research, The University of Mississippi, University, MS, 38677, USA
| | - Sebastian J Adams
- School of Pharmacy, National Center for Natural Products Research, The University of Mississippi, University, MS, 38677, USA
| | - Ikhlas A Khan
- School of Pharmacy, National Center for Natural Products Research, The University of Mississippi, University, MS, 38677, USA
| |
Collapse
|
21
|
Srivastava S, He F, Huang Y, Niu M, Adholeya A, Peng WK. A Brief Review on Medicinal Plants-At-Arms against COVID-19. Interdiscip Perspect Infect Dis 2023; 2023:7598307. [PMID: 37139479 PMCID: PMC10151152 DOI: 10.1155/2023/7598307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 03/09/2023] [Accepted: 03/22/2023] [Indexed: 05/05/2023] Open
Abstract
COVID-19 pandemic caused by the novel SARS-CoV-2 has impacted human livelihood globally. Strenuous efforts have been employed for its control and prevention; however, with recent reports on mutated strains with much higher infectivity, transmissibility, and ability to evade immunity developed from previous SARS-CoV-2 infections, prevention alternatives must be prepared beforehand in case. We have perused over 128 recent works (found on Google Scholar, PubMed, and ScienceDirect as of February 2023) on medicinal plants and their compounds for anti-SARS-CoV-2 activity and eventually reviewed 102 of them. The clinical application and the curative effect were reported high in China and in India. Accordingly, this review highlights the unprecedented opportunities offered by medicinal plants and their compounds, candidates as the therapeutic agent, against COVID-19 by acting as viral protein inhibitors and immunomodulator in (32 clinical trials and hundreds of in silico experiments) conjecture with modern science. Moreover, the associated foreseeable challenges for their viral outbreak management were discussed in comparison to synthetic drugs.
Collapse
Affiliation(s)
- Shivani Srivastava
- Centre for Mycorrhizal Research, Sustainable Agriculture Division, The Energy and Resources Institute (TERI), TERI Gram, Gwal Pahari, Gurugram 122001, India
| | - Fangzhou He
- Songshan Lake Materials Laboratory, University Innovation Park, Dongguan 523-808, China
| | - Yuanding Huang
- Songshan Lake Materials Laboratory, University Innovation Park, Dongguan 523-808, China
| | - Meng Niu
- China Medical University, Shenyang, China
| | - Alok Adholeya
- Centre for Mycorrhizal Research, Sustainable Agriculture Division, The Energy and Resources Institute (TERI), TERI Gram, Gwal Pahari, Gurugram 122001, India
| | - Weng Kung Peng
- Songshan Lake Materials Laboratory, University Innovation Park, Dongguan 523-808, China
| |
Collapse
|
22
|
Novel time-domain NMR-based traits for rapid, label-free Olive oils profiling. NPJ Sci Food 2022; 6:59. [PMID: 36513670 PMCID: PMC9746572 DOI: 10.1038/s41538-022-00173-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 11/30/2022] [Indexed: 12/15/2022] Open
Abstract
Olive oil is one of the oldest and essential edible oils in the market. The classification of olive oils (e.g. extra virgin, virgin, refined) is often influenced by factors ranging from its complex inherent physiochemical properties (e.g. fatty acid profiles) to the undisclosed manufacturing processes. Therefore, olive oils have been the target of adulteration due to its profitable margin. In this work, we demonstrate that multi-parametric time-domain NMR relaxometry can be used to rapidly (in minutes) identify and classify olive oils in label-free and non-destructive manner. The subtle differences in molecular microenvironment of the olive oils induce substantial changes in the relaxation mechanism in the time-domain NMR regime. We demonstrated that the proposed NMR-relaxation based detection (AUC = 0.95) is far more sensitive and specific than the current gold-standards in the field i.e. near-infrared spectroscopy (AUC = 0.84) and Ultraviolet-visible spectroscopy (AUC = 0.73), respectively. We further show that, albeit the inherent complexity of olive plant natural phenotypic variations, the proposed NMR-relaxation based traits may be a viable mean (AUC = 0.71) in tracing the regions of origin for olive trees, in agreement with their geographical orientation.
Collapse
|
23
|
Kil YS, Nam JW. Quantum-Mechanical Driven 1H Iterative Full Spin Analysis Addresses Complex Peak Patterns of Choline Sulfate. ACS OMEGA 2022; 7:42607-42612. [PMID: 36440115 PMCID: PMC9685754 DOI: 10.1021/acsomega.2c06092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 11/02/2022] [Indexed: 06/16/2023]
Abstract
Choline and choline esters are essential nutrients in biological systems for carrying out normal functions, such as the modulation of neurotransmission and the formation and maintenance of cell membranes. Choline sulfate is reportedly involved in the defense mechanism of accumulating sulfur resources against sulfur deficiency. Contrary to expectations, a full assignment of the 1H NMR spectrum of choline sulfate has not been reported. The present study pioneered a full assignment by quantum-mechanical driven 1H iterative full spin analysis. The complex peak patterns were analyzed in terms of heteronuclear and non-first-order coupling. The 1H-14N coupling constants, including two-bond coupling, which can be neglected, were accurately determined by iterative optimization. Non-first-order splitting has been described to be due to the presence of magnetically non-equivalent geminal protons. Moreover, in the comparison of the methylene proton resonance patterns of choline sulfate with choline and choline phosphate, the differences in the geminal and vicinal coupling constants were further examined through spectral simulation excluding the heteronuclear coupling. The precise spectral interpretation provided in this study is expected to contribute to future 1H NMR-based qualitative or quantitative studies of choline sulfate-containing sources.
Collapse
|
24
|
LF-NMR intelligent evaluation for lipid oxidation indices of polar compound distribution, fatty acid unsaturation, and dynamic viscosity: Preference and mechanism. Food Res Int 2022; 161:111807. [DOI: 10.1016/j.foodres.2022.111807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 07/28/2022] [Accepted: 08/18/2022] [Indexed: 11/17/2022]
|
25
|
Napolitano JG, Yang C, Conklin B, He Y, Ochoa JL. Toward the Development of Rapid, Automated Identification Tests for Neat Organic Liquids Using Benchtop NMR Instrumentation. Anal Chem 2022; 94:16095-16102. [DOI: 10.1021/acs.analchem.2c03276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- José G. Napolitano
- Small Molecule Pharmaceutical Sciences, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Cassie Yang
- Analytical Research and Development, AbbVie Inc., 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Breanna Conklin
- Small Molecule Pharmaceutical Sciences, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| | - Yan He
- Analytical Research and Development, AbbVie Inc., 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - Jessica L. Ochoa
- Small Molecule Pharmaceutical Sciences, Genentech Inc., 1 DNA Way, South San Francisco, California 94080, United States
| |
Collapse
|
26
|
Tadiello L, Drexler HJ, Beweries T. Low-Field Flow 31P NMR Spectroscopy for Organometallic Chemistry: On-Line Analysis of Highly Air-Sensitive Rhodium Diphosphine Complexes. Organometallics 2022. [DOI: 10.1021/acs.organomet.2c00301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Laura Tadiello
- Leibniz Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
| | - Hans-Joachim Drexler
- Leibniz Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
| | - Torsten Beweries
- Leibniz Institut für Katalyse e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
| |
Collapse
|
27
|
Migues I, Rivas F, Moyna G, Kelly SD, Heinzen H. Predicting Mandarin Fruit Acceptability: From High-Field to Benchtop NMR Spectroscopy. Foods 2022; 11:foods11162384. [PMID: 36010384 PMCID: PMC9407331 DOI: 10.3390/foods11162384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/29/2022] [Accepted: 08/01/2022] [Indexed: 11/30/2022] Open
Abstract
Recent advances in nuclear magnetic resonance (NMR) have led to the development of low-field benchtop NMR systems with improved sensitivity and resolution suitable for use in research and quality-control laboratories. Compared to their high-resolution counterparts, their lower purchase and running costs make them a good alternative for routine use. In this article, we show the adaptation of a method for predicting the consumer acceptability of mandarins, originally reported using a high-field 400 MHz NMR spectrometer, to benchtop 60 MHz NMR systems. Our findings reveal that both instruments yield comparable results regarding sugar and citric acid levels, leading to the development of virtually identical predictive linear models. However, the lower cost of benchtop NMR systems would allow cultivators to implement this chemometric-based method as an additional tool for the selection of new cultivars.
Collapse
Affiliation(s)
- Ignacio Migues
- Laboratorio de Farmacognosia y Productos Naturales, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, Montevideo 11800, Uruguay
- Programa de Posgrados de la Facultad de Química, Universidad de la República, Montevideo 11800, Uruguay
| | - Fernando Rivas
- Programa Nacional de Investigación en Producción Citrícola, Instituto Nacional de Investigación Agropecuaria (INIA), Salto 50000, Uruguay
| | - Guillermo Moyna
- Laboratorio de Espectroscopía y Fisicoquímica Orgánica, Departamento de Química del Litoral, CENUR Litoral Norte, Universidad de la República, Paysandú 60000, Uruguay
| | - Simon D. Kelly
- Food Safety Control Laboratory, Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, 1400 Vienna, Austria
| | - Horacio Heinzen
- Laboratorio de Farmacognosia y Productos Naturales, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, Montevideo 11800, Uruguay
- Correspondence: ; Tel.: +598-2924-4068
| |
Collapse
|
28
|
Parameter Visualization of Benchtop Nuclear Magnetic Resonance Spectra toward Food Process Monitoring. Processes (Basel) 2022. [DOI: 10.3390/pr10071264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022] Open
Abstract
Low-cost and user-friendly benchtop low-field nuclear magnetic resonance (NMR) spectrometers are typically used to monitor food processes in the food industry. Because of excessive spectral overlap, it is difficult to characterize food mixtures using low-field NMR spectroscopy. In addition, for standard compounds, low-field benchtop NMR data are typically unavailable compared to high-field NMR data, which have been accumulated and are reusable in public databases. This work focused on NMR parameter visualization of the chemical structure and mobility of mixtures and the use of high-field NMR data to analyze benchtop NMR data to characterize food process samples. We developed a tool to easily process benchtop NMR data and obtain chemical shifts and T2 relaxation times of peaks, as well as transform high-field NMR data into low-field NMR data. Line broadening and time–frequency analysis methods were adopted for data processing. This tool can visualize NMR parameters to characterize changes in the components and mobilities of food process samples using benchtop NMR data. In addition, assignment errors were smaller when the spectra of standard compounds were identified by transferring the high-field NMR data to low-field NMR data rather than directly using experimentally obtained low-field NMR spectra.
Collapse
|
29
|
Dickson CL, Peat G, Rossetto M, Halse ME, Uhrín D. SHARPER-enhanced benchtop NMR: improving SNR by removing couplings and approaching natural linewidths. Chem Commun (Camb) 2022; 58:5534-5537. [PMID: 35421881 DOI: 10.1039/d2cc01325h] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We present a signal enhancement strategy for benchtop NMR that produces SNR increases on the order of 10 to 30 fold by collapsing the target resonance into an extremely narrow singlet. Importantly, the resultant signal is amenable to quantitative interpretation and therefore can be applied to analytical applications such as reaction monitoring.
Collapse
Affiliation(s)
- Claire L Dickson
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK.
| | - George Peat
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK.
| | | | | | - Dušan Uhrín
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK.
| |
Collapse
|
30
|
Ben-Tal Y, Boaler PJ, Dale HJA, Dooley RE, Fohn NA, Gao Y, García-Domínguez A, Grant KM, Hall AMR, Hayes HLD, Kucharski MM, Wei R, Lloyd-Jones GC. Mechanistic analysis by NMR spectroscopy: A users guide. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 129:28-106. [PMID: 35292133 DOI: 10.1016/j.pnmrs.2022.01.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 06/14/2023]
Abstract
A 'principles and practice' tutorial-style review of the application of solution-phase NMR in the analysis of the mechanisms of homogeneous organic and organometallic reactions and processes. This review of 345 references summarises why solution-phase NMR spectroscopy is uniquely effective in such studies, allowing non-destructive, quantitative analysis of a wide range of nuclei common to organic and organometallic reactions, providing exquisite structural detail, and using instrumentation that is routinely available in most chemistry research facilities. The review is in two parts. The first comprises an introduction to general techniques and equipment, and guidelines for their selection and application. Topics include practical aspects of the reaction itself, reaction monitoring techniques, NMR data acquisition and processing, analysis of temporal concentration data, NMR titrations, DOSY, and the use of isotopes. The second part comprises a series of 15 Case Studies, each selected to illustrate specific techniques and approaches discussed in the first part, including in situ NMR (1/2H, 10/11B, 13C, 15N, 19F, 29Si, 31P), kinetic and equilibrium isotope effects, isotope entrainment, isotope shifts, isotopes at natural abundance, scalar coupling, kinetic analysis (VTNA, RPKA, simulation, steady-state), stopped-flow NMR, flow NMR, rapid injection NMR, pure shift NMR, dynamic nuclear polarisation, 1H/19F DOSY NMR, and in situ illumination NMR.
Collapse
Affiliation(s)
- Yael Ben-Tal
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Patrick J Boaler
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Harvey J A Dale
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Ruth E Dooley
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom; Evotec (UK) Ltd, 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire OX14 4RZ, United Kingdom
| | - Nicole A Fohn
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Yuan Gao
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Andrés García-Domínguez
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Katie M Grant
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Andrew M R Hall
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Hannah L D Hayes
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Maciej M Kucharski
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Ran Wei
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom
| | - Guy C Lloyd-Jones
- School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, United Kingdom.
| |
Collapse
|
31
|
Burger R, Lindner S, Rumpf J, Do XT, Diehl BW, Rehahn M, Monakhova YB, Schulze M. Benchtop versus high field NMR: Comparable performance found for the molecular weight determination of lignin. J Pharm Biomed Anal 2022; 212:114649. [DOI: 10.1016/j.jpba.2022.114649] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 10/19/2022]
|
32
|
3,4-Methylenedioxymethamphetamine Quantification via Benchtop 1H qNMR Spectroscopy: Method Validation and its Application to Ecstasy Tablets Collected at Music Festivals. J Pharm Biomed Anal 2022; 214:114728. [DOI: 10.1016/j.jpba.2022.114728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/10/2022] [Accepted: 03/14/2022] [Indexed: 11/17/2022]
|
33
|
Lindner S, Burger R, Rutledge DN, Do XT, Rumpf J, Diehl BWK, Schulze M, Monakhova YB. Is the Calibration Transfer of Multivariate Calibration Models between High- and Low-Field NMR Instruments Possible? A Case Study of Lignin Molecular Weight. Anal Chem 2022; 94:3997-4004. [PMID: 35201769 DOI: 10.1021/acs.analchem.1c05125] [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
Although several successful applications of benchtop nuclear magnetic resonance (NMR) spectroscopy in quantitative mixture analysis exist, the possibility of calibration transfer remains mostly unexplored, especially between high- and low-field NMR. This study investigates for the first time the calibration transfer of partial least squares regressions [weight average molecular weight (Mw) of lignin] between high-field (600 MHz) NMR and benchtop NMR devices (43 and 60 MHz). For the transfer, piecewise direct standardization, calibration transfer based on canonical correlation analysis, and transfer via the extreme learning machine auto-encoder method are employed. Despite the immense resolution difference between high-field and low-field NMR instruments, the results demonstrate that the calibration transfer from high- to low-field is feasible in the case of a physical property, namely, the molecular weight, achieving validation errors close to the original calibration (down to only 1.2 times higher root mean square errors). These results introduce new perspectives for applications of benchtop NMR, in which existing calibrations from expensive high-field instruments can be transferred to cheaper benchtop instruments to economize.
Collapse
Affiliation(s)
- Simon Lindner
- Department of Chemistry and Biotechnology, FH Aachen University of Applied Sciences, Jülich 52428, Germany.,Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach 53359, Germany
| | - René Burger
- Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach 53359, Germany
| | - Douglas N Rutledge
- Université Paris-Saclay, INRAE, AgroParisTech, UMR SayFood, Paris 75005, France.,National Wine and Grape Industry Centre, Charles Sturt University, Wagga Wagga 2650, Australia
| | - Xuan Tung Do
- Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach 53359, Germany
| | - Jessica Rumpf
- Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach 53359, Germany
| | - Bernd W K Diehl
- Spectral Service AG, Emil-Hoffmann-Straße 33, Köln 50996, Germany
| | - Margit Schulze
- Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach 53359, Germany
| | - Yulia B Monakhova
- Department of Chemistry and Biotechnology, FH Aachen University of Applied Sciences, Jülich 52428, Germany.,Spectral Service AG, Emil-Hoffmann-Straße 33, Köln 50996, Germany.,Institute of Chemistry, Saratov State University, Saratov 410012, Russia
| |
Collapse
|
34
|
Gunning Y, Taous F, El Ghali T, Gibbon JD, Wilson E, Brignall RM, Kemsley EK. Mitigating instrument effects in 60 MHz 1H NMR spectroscopy for authenticity screening of edible oils. Food Chem 2022; 370:131333. [PMID: 34788960 DOI: 10.1016/j.foodchem.2021.131333] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/01/2021] [Accepted: 10/03/2021] [Indexed: 11/04/2022]
Abstract
Low field (60 MHz) 1H NMR spectroscopy was used to analyse a large (n = 410) collection of edible oils, including olive and argan, in an authenticity screening scenario. Experimental work was carried out on multiple spectrometers at two different laboratories, aiming to explore multivariate model stability and transfer between instruments. Three modelling methods were employed: Partial Least Squares Discriminant Analysis, Random Forests, and a One Class Classification approach. Clear inter-instrument differences were observed between replicated data collections, sufficient to compromise effective transfer of models based on raw data between instruments. As mitigations to this issue, various data pre-treatments were investigated: Piecewise Direct Standardisation, Standard Normal Variates, and Rank Transformation. Datasets comprised both phase corrected and magnitude spectra, and it was found that that the latter spectral form may offer some advantages in the context of pattern recognition and classification modelling, particularly when used in combination with the Rank Transformation pre-treatment.
Collapse
Affiliation(s)
- Yvonne Gunning
- Quadram Institute Bioscience, Norwich Research Park, Colney, Norwich NR4 7UQ, UK
| | - Fouad Taous
- Centre National de l'Energie des Sciences et des Techniques Nucléaires (CNESTEN) Rabat, Morocco
| | - Tibari El Ghali
- Centre National de l'Energie des Sciences et des Techniques Nucléaires (CNESTEN) Rabat, Morocco
| | | | - E Wilson
- Quadram Institute Bioscience, Norwich Research Park, Colney, Norwich NR4 7UQ, UK
| | | | - E Kate Kemsley
- Quadram Institute Bioscience, Norwich Research Park, Colney, Norwich NR4 7UQ, UK.
| |
Collapse
|
35
|
Zhao J, Wang M, Saroja SG, Khan IA. NMR technique and methodology in botanical health product analysis and quality control. J Pharm Biomed Anal 2022; 207:114376. [PMID: 34656935 DOI: 10.1016/j.jpba.2021.114376] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/03/2021] [Accepted: 09/14/2021] [Indexed: 12/13/2022]
Abstract
Botanicals have played an important role in maintaining human health and well-being throughout history. During the past few decades in particular, the use of botanical health products has gained more popularity. Whereas, quality, safety and efficacy concerns have continuously been critical issues due to the intrinsic chemical complexity of botanicals. Chemical analytical technologies play an imperative role in addressing these issues. Nuclear magnetic resonance (NMR) spectroscopy has proven to be a powerful and useful tool for the investigation of botanical health products. In this review, NMR techniques and methodologies that have been successfully applied to the research and development of botanical health products in all stages, from plants to products, are discussed and summarized. Furthermore, applications of NMR together with other analytical techniques in a variety of domains of botanical health products investigation, such as plant species differentiation, adulteration detection, and bio-activity evaluation, are discussed and illustrated with typical examples. This article provides an overview of the potential uses of NMR techniques and methodologies in an attempt to further promote their recognition and utilization in the field of botanical health products analysis and quality control.
Collapse
Affiliation(s)
- Jianping Zhao
- National Center for Natural Products Research (NCNPR), School of Pharmacy, University of Mississippi, University, MS 38677, USA.
| | - Mei Wang
- Natural Products Utilization Research Unit, Agricultural Research Service, US Department of Agriculture, University, MS 38677, USA
| | - Seethapathy G Saroja
- National Center for Natural Products Research (NCNPR), School of Pharmacy, University of Mississippi, University, MS 38677, USA
| | - Ikhlas A Khan
- National Center for Natural Products Research (NCNPR), School of Pharmacy, University of Mississippi, University, MS 38677, USA; Division of Pharmacognosy, Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA.
| |
Collapse
|
36
|
Geographical Origin Assessment of Extra Virgin Olive Oil via NMR and MS Combined with Chemometrics as Analytical Approaches. Foods 2022; 11:foods11010113. [PMID: 35010239 PMCID: PMC8750049 DOI: 10.3390/foods11010113] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/06/2021] [Accepted: 12/28/2021] [Indexed: 12/17/2022] Open
Abstract
Geographical origin assessment of extra virgin olive oil (EVOO) is recognised worldwide as raising consumers’ awareness of product authenticity and the need to protect top-quality products. The need for geographical origin assessment is also related to mandatory legislation and/or the obligations of true labelling in some countries. Nevertheless, official methods for such specific authentication of EVOOs are still missing. Among the analytical techniques useful for certification of geographical origin, nuclear magnetic resonance (NMR) and mass spectroscopy (MS), combined with chemometrics, have been widely used. This review considers published works describing the use of these analytical methods, supported by statistical protocols such as multivariate analysis (MVA), for EVOO origin assessment. The research has shown that some specific countries, generally corresponding to the main worldwide producers, are more interested than others in origin assessment and certification. Some specific producers such as Italian EVOO producers may have been focused on this area because of consumers’ interest and/or intrinsic economical value, as testified also by the national concern on the topic. Both NMR- and MS-based approaches represent a mature field where a general validation method for EVOOs geographic origin assessment could be established as a reference recognised procedure.
Collapse
|
37
|
McDevitt JC, Gupta RA, Dickinson SG, Martin PL, Rieuthavorn J, Freund A, Pizzorno MC, Capaldi EA, Rovnyak D. Methodology for Single Bee and Bee Brain 1H-NMR Metabolomics. Metabolites 2021; 11:metabo11120864. [PMID: 34940622 PMCID: PMC8704342 DOI: 10.3390/metabo11120864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/07/2021] [Accepted: 12/07/2021] [Indexed: 11/16/2022] Open
Abstract
The feasibility of metabolomic 1H NMR spectroscopy is demonstrated for its potential to help unravel the complex factors that are impacting honeybee health and behavior. Targeted and non-targeted 1H NMR metabolic profiles of liquid and tissue samples of organisms could provide information on the pathology of infections and on environmentally induced stresses. This work reports on establishing extraction methods for NMR metabolic characterization of Apis mellifera, the European honeybee, describes the currently assignable aqueous metabolome, and gives examples of diverse samples (brain, head, body, whole bee) and biologically meaningful metabolic variation (drone, forager, day old, deformed wing virus). Both high-field (600 MHz) and low-field (80 MHz) methods are applicable, and 1H NMR can observe a useful subset of the metabolome of single bees using accessible NMR instrumentation (600 MHz, inverse room temperature probe) in order to avoid pooling several bees. Metabolite levels and changes can be measured by NMR in the bee brain, where dysregulation of metabolic processes has been implicated in colony collapse. For a targeted study, the ability to recover 10-hydroxy-2-decenoic acid in mandibular glands is shown, as well as markers of interest in the bee brain such as GABA (4-aminobutyrate), proline, and arginine. The findings here support the growing use of 1H NMR more broadly in bees, native pollinators, and insects.
Collapse
Affiliation(s)
- Jayne C. McDevitt
- Department of Chemistry, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.C.M.); (R.A.G.); (S.G.D.); (P.L.M.)
| | - Riju A. Gupta
- Department of Chemistry, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.C.M.); (R.A.G.); (S.G.D.); (P.L.M.)
| | - Sydney G. Dickinson
- Department of Chemistry, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.C.M.); (R.A.G.); (S.G.D.); (P.L.M.)
| | - Phillip L. Martin
- Department of Chemistry, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.C.M.); (R.A.G.); (S.G.D.); (P.L.M.)
| | - Jean Rieuthavorn
- Department of Biology, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.R.); (M.C.P.); (E.A.C.)
| | - Amy Freund
- Bruker Biospin, 15 Fortune Drive, Billerica, MA 01821, USA;
| | - Marie C. Pizzorno
- Department of Biology, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.R.); (M.C.P.); (E.A.C.)
| | - Elizabeth A. Capaldi
- Department of Biology, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.R.); (M.C.P.); (E.A.C.)
- Program in Animal Behavior, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA
| | - David Rovnyak
- Department of Chemistry, Bucknell University, 1 Dent Drive, Lewisburg, PA 17837, USA; (J.C.M.); (R.A.G.); (S.G.D.); (P.L.M.)
- Correspondence:
| |
Collapse
|
38
|
Nagata T. New Algorithm by Maximizing Mutual Information for Correction of Frequency Drifts Arising from One-Dimensional NMR Spectroscopic Data Acquisition. ACS OMEGA 2021; 6:31299-31304. [PMID: 34841174 PMCID: PMC8613858 DOI: 10.1021/acsomega.1c05143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/29/2021] [Indexed: 06/13/2023]
Abstract
Benchtop nuclear magnetic resonance (NMR) instruments are getting popular these days. However, the obtained spectra sometimes suffer from significant frequency drifts, which cause difficulty in accumulating the raw data. In this paper, a new algorithm for correction of frequency drifts is proposed, which operates by maximizing mutual information between the obtained spectroscopic data. The algorithm worked well for both 1H and 19F NMR spectroscopic data, even in the case of very noisy ones. In comparison with the previously reported algorithms, the present algorithm has an advantage that NMR spectra complicated by signal overlapping and spin coupling can be handled without difficulty. This makes the present algorithm particularly advantageous for application of benchtop NMR spectrometers in organic chemistry.
Collapse
|
39
|
Lee Y, Matviychuk Y, Park H, Wang L, Holland DJ. Quantitative frother analysis on coal mine process water with a benchtop NMR spectrometer. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 331:107054. [PMID: 34450434 DOI: 10.1016/j.jmr.2021.107054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 06/08/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
This paper investigates the use of a benchtop NMR for quantification of a commonly used frothing agent, methyl isobutyl carbinol (MIBC) in the process water of a coal preparation facility. Solid phase extraction is used to increase the concentration of MIBC in the sample so that it is quantifiable by a benchtop NMR. A polymeric, reversed phase column with methanol as solvent gives a MIBC recovery rate of 67 ± 4% as determined using 400 MHz high-field NMR. The recovery rate consistently falls in the above narrow range even in the presence of diesel and inorganic electrolytes which are likely present as background chemicals in the process water. Using the average MIBC recovery rate, we use a quantum mechanical model to analyse the intensity of MIBC in the benchtop spectra. The quantum mechanical modelling algorithm effectively excludes the effect of the diesel on the measured NMR signal. The quantification error when the inlet concentration of MIBC is between 1 and 12 mg/L (1.2-15 ppm v/v), is within 0.5 mg/L (0.6 ppm v/v).
Collapse
Affiliation(s)
- Yejin Lee
- University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - Yevgen Matviychuk
- University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
| | - Hangil Park
- The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Liguang Wang
- The University of Queensland, St Lucia, Queensland 4072, Australia.
| | - Daniel J Holland
- University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
| |
Collapse
|
40
|
Dyga M, Oppel C, Gooßen LJ. RotoMate: An open-source, 3D printed autosampler for use with benchtop nuclear magnetic resonance spectrometers. HARDWAREX 2021; 10:e00211. [PMID: 35607663 PMCID: PMC9123427 DOI: 10.1016/j.ohx.2021.e00211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/16/2021] [Accepted: 06/17/2021] [Indexed: 06/15/2023]
Abstract
Benchtop nuclear magnetic resonance (NMR) spectrometers are versatile analytic instruments with low acquisition and operation cost. However, in the basic version, samples must be manually measured one after the other. We herein describe the open-source autosampler RotoMate that allows the automated operation of such instruments. The hardware is easily assembled from 3D-printed and inexpensive off-the-shelf parts, and is controlled by an Arduino Uno. A software package interlinks the operation of the autosampler with the software of the NMR spectrometer and the software for the processing of the spectra. Experiments for up to 30 samples can be inserted into an interactive sample list. The autosampler automatically inserts and ejects the samples, initiates measurements on the spectrometer according to parameters specified in the sample list, and interacts with a common NMR software in the processing and visualization of the obtained spectroscopic raw data. If an internal standard is present, conversions and yields of chemical reactions are automatically calculated, enabling e.g. the monitoring of reactions. The device was fitted to a Magritek Spinsolve instrument and can interact with a free academic version of ACD NMR software to process the spectra, but can likely be adapted to similar instruments and spectroscopy software packages.
Collapse
|
41
|
Abstract
Benchtop nuclear magnetic resonance (NMR) spectroscopy uses small permanent magnets to generate magnetic fields and therefore offers the advantages of operational simplicity and reasonable cost, presenting a viable alternative to high-field NMR spectroscopy. In particular, the use of benchtop NMR spectroscopy for rapid in-field analysis, e.g., for quality control or forensic science purposes, has attracted considerable attention. As benchtop NMR spectrometers are sufficiently compact to be operated in a fume hood, they can be efficiently used for real-time reaction and process monitoring. This review introduces the recent applications of benchtop NMR spectroscopy in diverse fields, including food science, pharmaceuticals, process and reaction monitoring, metabolomics, and polymer materials.
Collapse
|
42
|
Joulain D. Jasminum grandiflorum
flowers—Phytochemical complexity and its capture in extracts: a review. FLAVOUR FRAG J 2021. [DOI: 10.1002/ffj.3672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
43
|
Soheilmoghaddam F, Rumble M, Cooper-White J. High-Throughput Routes to Biomaterials Discovery. Chem Rev 2021; 121:10792-10864. [PMID: 34213880 DOI: 10.1021/acs.chemrev.0c01026] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many existing clinical treatments are limited in their ability to completely restore decreased or lost tissue and organ function, an unenviable situation only further exacerbated by a globally aging population. As a result, the demand for new medical interventions has increased substantially over the past 20 years, with the burgeoning fields of gene therapy, tissue engineering, and regenerative medicine showing promise to offer solutions for full repair or replacement of damaged or aging tissues. Success in these fields, however, inherently relies on biomaterials that are engendered with the ability to provide the necessary biological cues mimicking native extracellular matrixes that support cell fate. Accelerating the development of such "directive" biomaterials requires a shift in current design practices toward those that enable rapid synthesis and characterization of polymeric materials and the coupling of these processes with techniques that enable similarly rapid quantification and optimization of the interactions between these new material systems and target cells and tissues. This manuscript reviews recent advances in combinatorial and high-throughput (HT) technologies applied to polymeric biomaterial synthesis, fabrication, and chemical, physical, and biological screening with targeted end-point applications in the fields of gene therapy, tissue engineering, and regenerative medicine. Limitations of, and future opportunities for, the further application of these research tools and methodologies are also discussed.
Collapse
Affiliation(s)
- Farhad Soheilmoghaddam
- Tissue Engineering and Microfluidics Laboratory (TEaM), Australian Institute for Bioengineering and Nanotechnology (AIBN), University Of Queensland, St. Lucia, Queensland, Australia 4072.,School of Chemical Engineering, University Of Queensland, St. Lucia, Queensland, Australia 4072
| | - Madeleine Rumble
- Tissue Engineering and Microfluidics Laboratory (TEaM), Australian Institute for Bioengineering and Nanotechnology (AIBN), University Of Queensland, St. Lucia, Queensland, Australia 4072.,School of Chemical Engineering, University Of Queensland, St. Lucia, Queensland, Australia 4072
| | - Justin Cooper-White
- Tissue Engineering and Microfluidics Laboratory (TEaM), Australian Institute for Bioengineering and Nanotechnology (AIBN), University Of Queensland, St. Lucia, Queensland, Australia 4072.,School of Chemical Engineering, University Of Queensland, St. Lucia, Queensland, Australia 4072
| |
Collapse
|
44
|
Wang XY, Xie J, Chen XJ. Applications of Non-invasive and Novel Methods of Low-Field Nuclear Magnetic Resonance and Magnetic Resonance Imaging in Aquatic Products. Front Nutr 2021; 8:651804. [PMID: 33869268 PMCID: PMC8044990 DOI: 10.3389/fnut.2021.651804] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 02/22/2021] [Indexed: 01/13/2023] Open
Abstract
Aquatic products, such as fish, are popular throughout the world due to their satisfying flavor characteristics as well as rich animal nutrition, and they provide high-value food therapy, but they are easily oxidized and spoiled. It is necessary to detect aquatic products through rapid and accurate technology. Low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) have been widely used in the aquatic product industry due to their sensitivity, fast analysis, non-destructive nature and low cost. The applications of LF-NMR in the measurement of aquatic product quality and nutrients (water, fat, and protein) are summarized in this paper. Applications in aquatic products have been shown to depend on deep processing, storage and authentication. This review discusses the application of MRI technology in the quality control of aquatic products. Therefore, this review will guide the application of the aquatic products industry and aims to supply the reader with both the theory of the method and practical applications of the method for use as a rapid and non-destructive technology in scientific research and the industrial industry.
Collapse
Affiliation(s)
- Xin-Yun Wang
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai, China.,Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai, China.,National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, China.,College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| | - Jing Xie
- Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai, China.,Shanghai Professional Technology Service Platform on Cold Chain Equipment Performance and Energy Saving Evaluation, Shanghai, China.,National Experimental Teaching Demonstration Center for Food Science and Engineering, Shanghai Ocean University, Shanghai, China.,College of Food Science and Technology, Shanghai Ocean University, Shanghai, China
| | - Xin-Jun Chen
- College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| |
Collapse
|
45
|
Höpfner J, Mayerhöfer B, Botha C, Bouillaud D, Farjon J, Giraudeau P, Wilhelm M. Solvent suppression techniques for coupling of size exclusion chromatography and 1H NMR using benchtop spectrometers at 43 and 62 MHz. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 323:106889. [PMID: 33518176 DOI: 10.1016/j.jmr.2020.106889] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 12/03/2020] [Accepted: 12/06/2020] [Indexed: 06/12/2023]
Abstract
The characterisation of polymeric materials in their full complexity of chain length, monomeric composition, branching and functionalization is a tremendous challenge and is best tackled by tailored multi-dimensional coupled analytical and detection techniques. Herein, we focus on the improvement of an affordable but information rich 2D-method for polymer analysis: the online hyphenation of benchtop 1H NMR spectroscopy with size exclusion chromatography (SEC). The main benefit of this approach is correlated information of chain length (SEC) to chemical composition (1H NMR). Our setup combines SEC onflow with a benchtop NMR spectrometer at 43 or 62 MHz with chemical shift resolution as a robust detector. A detailed comparison of the two instruments is included considering, that only the 43 MHz instrument is equipped with a dedicated z-gradient enabling pulse sequences such as WET. The main challenge of this method is the very low concentration of species of interest after chromatographic separation. At typical SEC conditions, the analyte dilution is typically more than a factor of 1000:1 in a protonated solvent. Therefore, an efficient solvent signal suppression is needed. In this article, several suppression pulse sequences are explored like WET, WEFT, JNR and a simple one-pulse approach - some for the first time on this hardware. By choosing an optimal method, signal strength ratios of solvent to analyte of 1:1 or better are achievable on flow. To illustrate the broad range of possible applications, three typical cases of analyte to solvent signal proximity (no overlap, partial and full overlap) are discussed using typical polymers (PS, PMMA, PEMA) and solvents (chloroform and THF). For each case, several suppression methods are compared and evaluated using a set of numerical criteria (analyte signal suppression and broadening, solvent signal suppression, remaining solvent signal width).
Collapse
Affiliation(s)
- J Höpfner
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, Engesserstr. 18, 76131 Karlsruhe, Germany
| | - B Mayerhöfer
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, Engesserstr. 18, 76131 Karlsruhe, Germany
| | - C Botha
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, Engesserstr. 18, 76131 Karlsruhe, Germany
| | - D Bouillaud
- Université de Nantes, CNRS, CEISAM UMR 6230, F-44000 Nantes, France
| | - J Farjon
- Université de Nantes, CNRS, CEISAM UMR 6230, F-44000 Nantes, France
| | - P Giraudeau
- Université de Nantes, CNRS, CEISAM UMR 6230, F-44000 Nantes, France.
| | - M Wilhelm
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, Engesserstr. 18, 76131 Karlsruhe, Germany.
| |
Collapse
|
46
|
Chemometric Analysis of Low-field 1H NMR Spectra for Unveiling Adulteration of Slimming Dietary Supplements by Pharmaceutical Compounds. Molecules 2020; 25:molecules25051193. [PMID: 32155779 PMCID: PMC7179456 DOI: 10.3390/molecules25051193] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 12/29/2022] Open
Abstract
The recent introduction of compact or low-field (LF) NMR spectrometers that use permanent magnets, giving rise to proton (1H) NMR frequencies between 40 and 80 MHz, have opened up new areas of application. The two main limitations of the technique are its insensitivity and poor spectral resolution. However, this study demonstrates that the chemometric treatment of LF 1H NMR spectral data is suitable for unveiling medicines as adulterants of slimming dietary supplements (DS). To this aim, 66 DS were analyzed with LF 1H NMR after quick and easy sample preparation. A first PLS-DA model built with the LF 1H NMR spectra from forty DS belonging to two classes of weight-loss DS (non-adulterated, and sibutramine or phenolphthalein-adulterated) led to the classification of 13 newly purchased test samples as natural, adulterated or borderline. This classification was further refined when the model was made from the same 40 DS now considered as representing three classes of DS (non-adulterated, sibutramine-adulterated, and phenolphthalein-adulterated). The adulterant (sibutramine or phenolphthalein) was correctly predicted as confirmed by the examination of the 1H NMR spectra. A limitation of the chemometric approach is discussed with the example of two atypical weight-loss DS containing fluoxetine or raspberry ketone.
Collapse
|