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Tayler MCD, Bodenstedt S. NMRduino: A modular, open-source, low-field magnetic resonance platform. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 362:107665. [PMID: 38598992 DOI: 10.1016/j.jmr.2024.107665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/06/2024] [Accepted: 03/20/2024] [Indexed: 04/12/2024]
Abstract
The NMRduino is a compact, cost-effective, sub-MHz NMR spectrometer that utilizes readily available open-source hardware and software components. One of its aims is to simplify the processes of instrument setup and data acquisition control to make experimental NMR spectroscopy accessible to a broader audience. In this introductory paper, the key features and potential applications of NMRduino are described to highlight its versatility both for research and education.
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Affiliation(s)
- Michael C D Tayler
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain.
| | - Sven Bodenstedt
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
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2
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Guo T, He W, Wan C, Zhang Y, Xu Z. NMR Magnetometer Based on Dynamic Nuclear-Polarization for Low-Strength Magnetic Field Measurement. SENSORS (BASEL, SWITZERLAND) 2023; 23:4663. [PMID: 37430578 DOI: 10.3390/s23104663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/29/2023] [Accepted: 05/09/2023] [Indexed: 07/12/2023]
Abstract
Nuclear magnetic resonance (NMR) magnetometers are considered due to their ability to map magnetic fields with high precision and calibrate other magnetic field measurement devices. However, the low signal-to-noise ratio of low-strength magnetic fields limits the precision when measuring magnetic fields below 40 mT. Therefore, we developed a new NMR magnetometer that combines the dynamic nuclear polarization (DNP) technique with pulsed NMR. The dynamic pre-polarization technique enhances the SNR under a low magnetic field. Pulsed NMR was used in conjunction with DNP to improve measurement accuracy and speed. The efficacy of this approach was validated through simulation and analysis of the measurement process. Next, a complete set of equipment was constructed, and we successfully measured magnetic fields of 30 mT and 8 mT with an accuracy of only 0.5 Hz (11 nT) at 30 mT (0.4 ppm) and 1 Hz (22 nT) at 8mT (3 ppm).
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Affiliation(s)
- Taoning Guo
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China
| | - Wei He
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China
| | - Cai Wan
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China
| | - Yuxiang Zhang
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China
| | - Zheng Xu
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China
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3
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Reisenbauer S, Behal P, Wachter G, Trupke M. LithPulser: An open-source pulse generator with 1 ns time resolution based on the Red Pitaya STEMlab 125-10 featuring real-time conditional logic for experimental control. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:014708. [PMID: 35104955 DOI: 10.1063/5.0058786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Many experiments in the physical sciences require high temporal resolution on multiple control channels and can benefit from conditional logic control of the experimental sequence patterns. We present LithPulser, a field programmable gate array (FPGA) based open-source digital pulser solution with 1 ns time resolution on 14 digital output channels. The pulser is set up on the affordable Xilinx Zynq-7010 FPGA in the form of the Red Pitaya STEMlab board 125-10. It offers up to 125 MHz bandwidth and a sequence duration of up to 4.2 s and features 16 sequence play control, including a conditional logic module reactive to input events in real-time. LithPulser is designed for a trial until success experimental use case.
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Affiliation(s)
- S Reisenbauer
- Institute for Atomic and Subatomic Physics, Vienna University of Technology, VCQ, Stadionallee 2, 1020 Vienna, Austria
| | - P Behal
- Institute for Atomic and Subatomic Physics, Vienna University of Technology, VCQ, Stadionallee 2, 1020 Vienna, AustriaFaculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, 1090 Vienna, Austria
| | - G Wachter
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, 1090 Vienna, Austria
| | - M Trupke
- Faculty of Physics, University of Vienna, VCQ, Boltzmanngasse 5, 1090 Vienna, Austria
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4
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Bryden N, Antonacci M, Kelley M, Branca RT. An open-source, low-cost NMR spectrometer operating in the mT field regime. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 332:107076. [PMID: 34624719 PMCID: PMC9208334 DOI: 10.1016/j.jmr.2021.107076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
In recent years, low field and ultra-low field NMR spectrometers have gained interest due to their portability, lower cost, and reduced subject-induced magnetic field inhomogeneities. Here, we describe the design of a low-cost multinuclear NMR spectrometer operating in the ultra-low field regime (ULF), which possesses high spectral resolution and enables arbitrary pulse programming. An inexpensive multifunction input/output (I/O) device is used to handle waveform generation and digitization in the kHz operating range. A home-built radio frequency (RF) mixing circuit is used to down-mix the NMR signals, allowing for the slower sampling rates and lower memory requirements needed to enable minute-long acquisitions using a standard Windows PC. The LabVIEW code, along with a bill of materials for all components used in the spectrometer, is included. As proof of concept, 1H relaxation measurements and the simultaneous detection of 1H with gas phase and dissolved 129Xe frequencies using the described low field NMR spectrometer are demonstrated.
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Affiliation(s)
- Nicholas Bryden
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Michael Antonacci
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Michele Kelley
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Rosa T Branca
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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5
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Kelz JI, Uribe JL, Martin RW. Reimagining magnetic resonance instrumentation using open maker tools and hardware as protocol. JOURNAL OF MAGNETIC RESONANCE OPEN 2021; 6-7:100011. [PMID: 34085051 PMCID: PMC8171197 DOI: 10.1016/j.jmro.2021.100011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Over the course of its history, the field of nuclear magnetic resonance spectroscopy has been characterized by alternating periods of intensive instrumentation development and rapid expansion into new chemical application areas. NMR is now both a mainstay of routine analysis for laboratories at all levels of education and research. On the other hand, new instrumentation and methodological advances promise expanded functionality in the future. At the core of this success is a community fundamentally dedicated to sharing ideas and collaborative advancements, as exemplified by the extensive remixing and repurposing of pulse sequences. Recent progress in modularity, automation, and 3D printing have reignited the tinkering spirit and demonstrate great promise to mature into a maker space that will enable similarly facile sharing of new applications and broader access to magnetic resonance.
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Affiliation(s)
- Jessica I. Kelz
- Department of Chemistry, University of California, Irvine 92697-2025
| | - Jose L. Uribe
- Department of Chemistry, University of California, Irvine 92697-2025
| | - Rachel W. Martin
- Department of Chemistry, University of California, Irvine 92697-2025
- Department of Molecular Biology and Biochemistry, University of California, Irvine 92697-3900
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6
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Birchall JR, Irwin RK, Chowdhury MRH, Nikolaou P, Goodson BM, Barlow MJ, Shcherbakov A, Chekmenev EY. Automated Low-Cost In Situ IR and NMR Spectroscopy Characterization of Clinical-Scale 129Xe Spin-Exchange Optical Pumping. Anal Chem 2021; 93:3883-3888. [PMID: 33591160 DOI: 10.1021/acs.analchem.0c04545] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present on the utility of in situ nuclear magnetic resonance (NMR) and near-infrared (NIR) spectroscopic techniques for automated advanced analysis of the 129Xe hyperpolarization process during spin-exchange optical pumping (SEOP). The developed software protocol, written in the MATLAB programming language, facilitates detailed characterization of hyperpolarized contrast agent production efficiency based on determination of key performance indicators, including the maximum achievable 129Xe polarization, steady-state Rb-129Xe spin-exchange and 129Xe polarization build-up rates, 129Xe spin-relaxation rates, and estimates of steady-state Rb electron polarization. Mapping the dynamics of 129Xe polarization and relaxation as a function of SEOP temperature enables systematic optimization of the batch-mode SEOP process. The automated analysis of a typical experimental data set, encompassing ∼300 raw NMR and NIR spectra combined across six different SEOP temperatures, can be performed in under 5 min on a laptop computer. The protocol is designed to be robust in operation on any batch-mode SEOP hyperpolarizer device. In particular, we demonstrate the implementation of a combination of low-cost NIR and low-frequency NMR spectrometers (∼$1,100 and ∼$300 respectively, ca. 2020) for use in the described protocols. The demonstrated methodology will aid in the characterization of NMR hyperpolarization hardware in the context of SEOP and other hyperpolarization techniques for more robust and less expensive clinical production of HP 129Xe and other contrast agents.
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Affiliation(s)
- Jonathan R Birchall
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan 48202, United States
| | - Robert K Irwin
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Md Raduanul H Chowdhury
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan 48202, United States
| | | | | | - Michael J Barlow
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | - Anton Shcherbakov
- Smart-A, Perm, Perm Region 614000, Russia.,Custom Medical Systems (CMS) LTD, Nicosia 2312, Cyprus
| | - Eduard Y Chekmenev
- Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan 48202, United States.,Russian Academy of Sciences, Leninskiy Prospekt 14, Moscow 119991, Russia
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7
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Windt CW, Nabel M, Kochs J, Jahnke S, Schurr U. A Mobile NMR Sensor and Relaxometric Method to Non-destructively Monitor Water and Dry Matter Content in Plants. FRONTIERS IN PLANT SCIENCE 2021; 12:617768. [PMID: 33613603 PMCID: PMC7892787 DOI: 10.3389/fpls.2021.617768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 01/05/2021] [Indexed: 05/23/2023]
Abstract
Water content (WC) and dry matter content (DMC) are some of the most basic parameters to describe plant growth and yield, but are exceptionally difficult to measure non-invasively. Nuclear Magnetic Resonance (NMR) relaxometry may fill this methodological gap. It allows non-invasive detection of protons in liquids and solids, and on the basis of these measures, can be used to quantify liquid and dry matter contents of seeds and plants. Unfortunately, most existing NMR relaxometers are large, unwieldy and not suitable to measure intact plants or to be used under field conditions. In addition, currently the appropriate NMR relaxometric methods are poorly suited for non-expert use. We here present a novel approach to overcome these drawbacks. We demonstrate that a basic NMR relaxometer with the capability to accept intact plants, in combination with straightforward NMR and data processing methods, can be used as an NMR plant sensor to continuously, quantitatively and non-invasively monitor changes in WC and DMC. This can be done in vivo, in situ, and with high temporal resolution. The method is validated by showing that measured liquid and solid proton densities accurately reflect WC and DMC of reference samples. The NMR plant sensor is demonstrated in an experimental context by monitoring WC of rice leaves under osmotic stress, and by measuring the dynamics of water and dry matter accumulation during seed filling in a developing wheat ear. It is further demonstrated how the method can be used to estimate leaf water potential on the basis of changes in leaf water content.
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Affiliation(s)
- Carel W. Windt
- Institute for Bio- and Geosciences IBG-2: Plant Sciences, Forschungszentrum Jülich, Jülich, Germany
| | - Moritz Nabel
- Institute for Bio- and Geosciences IBG-2: Plant Sciences, Forschungszentrum Jülich, Jülich, Germany
| | - Johannes Kochs
- Institute for Bio- and Geosciences IBG-2: Plant Sciences, Forschungszentrum Jülich, Jülich, Germany
| | - Siegfried Jahnke
- Institute for Bio- and Geosciences IBG-2: Plant Sciences, Forschungszentrum Jülich, Jülich, Germany
- Faculty of Biology Biodiversity, University of Duisburg-Essen, Essen, Germany
| | - Ulrich Schurr
- Institute for Bio- and Geosciences IBG-2: Plant Sciences, Forschungszentrum Jülich, Jülich, Germany
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8
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Biller JR, McPeak JE. EPR Everywhere. APPLIED MAGNETIC RESONANCE 2021; 52:1113-1139. [PMID: 33519097 PMCID: PMC7826499 DOI: 10.1007/s00723-020-01304-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 10/16/2020] [Accepted: 12/06/2020] [Indexed: 06/12/2023]
Abstract
This review is inspired by the contributions from the University of Denver group to low-field EPR, in honor of Professor Gareth Eaton's 80th birthday. The goal is to capture the spirit of innovation behind the body of work, especially as it pertains to development of new EPR techniques. The spirit of the DU EPR laboratory is one that never sought to limit what an EPR experiment could be, or how it could be applied. The most well-known example of this is the development and recent commercialization of rapid-scan EPR. Both of the Eatons have made it a point to remain knowledgeable on the newest developments in electronics and instrument design. To that end, our review touches on the use of miniaturized electronics and applications of single-board spectrometers based on software-defined radio (SDR) implementations and single-chip voltage-controlled oscillator (VCO) arrays. We also highlight several non-traditional approaches to the EPR experiment such as an EPR spectrometer with a "wand" form factor for analysis of the OxyChip, the EPR-MOUSE which enables non-destructive in situ analysis of many non-conforming samples, and interferometric EPR and frequency swept EPR as alternatives to classical high Q resonant structures.
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Affiliation(s)
| | - Joseph E. McPeak
- University of Denver, Denver, CO 80210 USA
- Berlin Joint EPR Laboratory and EPR4Energy, Department Spins in Energy Conversion and Quantum Information Science (ASPINS), Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
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9
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McDaniel PC, Cooley CZ, Stockmann JP, Wald LL. The MR Cap: A single-sided MRI system designed for potential point-of-care limited field-of-view brain imaging. Magn Reson Med 2019; 82:1946-1960. [PMID: 31231885 DOI: 10.1002/mrm.27861] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/06/2019] [Accepted: 05/23/2019] [Indexed: 01/08/2023]
Abstract
PURPOSE The size, cost, and siting requirements of conventional MRI systems limit their availability and preclude usage as monitoring or point-of-care devices. To address this, we developed a lightweight MRI for point-of-care brain imaging over a reduced field of view (FOV). METHODS The B0 magnet was designed with a genetic algorithm optimizing homogeneity over a 3 × 8 × 8 cm FOV and a built-in gradient for slice selection or readout encoding. An external pair of gradient coils enables phase encoding in the other two directions and a radiofrequency (RF) coil provides excitation and detection. The system was demonstrated with high-resolution 1D "depth profiling" and 3D phantom imaging. RESULTS The lightweight B0 magnet achieved a 64-mT average field over the imaging region at a materials cost of <$450 USD. The weight of the magnet, gradient, and RF coil was 8.3 kg. Depth profiles were obtained at high resolution (0.89 mm) and multislice rapid acquisition with refocused echoes (RARE) images were obtained with a resolution ~2 mm in-plane and ~6-mm slice thickness, each in an imaging time of 11 min. CONCLUSION The system demonstrates the feasibility of a lightweight brain MRI system capable of 1D to 3D imaging within a reduced FOV. The proposed system is low-cost and small enough to be used in point-of-care applications.
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Affiliation(s)
- Patrick C McDaniel
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts.,Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts
| | - Clarissa Zimmerman Cooley
- Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Jason P Stockmann
- Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Lawrence L Wald
- Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts.,Harvard Medical School, Boston, Massachusetts.,Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, Massachusetts
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Ariando D, Chen C, Greer M, Mandal S. An autonomous, highly portable NMR spectrometer based on a low-cost System-on-Chip (SoC). JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 299:74-92. [PMID: 30590351 DOI: 10.1016/j.jmr.2018.12.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 05/13/2023]
Abstract
This paper describes the development of a portable and self-optimizing NMR spectrometer based on a miniaturized custom analog front-end and a System-on-Chip (SoC)-based digital back-end. The SoC integrates a field-programmable gate array (FPGA) fabric with a hard processor running a Linux operating system, thus enabling fully-autonomous operation without the need for an external computer. In the proposed approach, data captured by the FPGA fabric during regular operation is transported to the hard processor using an integrated on-chip bus for further processing. The processed results are then used to automatically estimate parameter values that optimize a suitable cost function, such as signal-to-noise ratio (SNR) per unit time. Finally, the optimized values of both electrical and NMR-related tuning parameters (e.g., preamplifier gain and frequency response, pulse length and amplitude, operating frequency, etc.) are programmed back into the front-end and back-end hardware. Experimental NMR results from various samples in a ∼0.1 T permanent magnet are presented to verify the operation of the proposed spectrometer. These demonstrate on-board Laplace inversion and automated frequency tuning to compensate for temperature changes. Preliminary 14N NQR results are also presented.
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Affiliation(s)
- David Ariando
- Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
| | - Cheng Chen
- Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
| | - Mason Greer
- Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
| | - Soumyajit Mandal
- Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
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Hibino Y, Sugahara K, Muro Y, Tanaka H, Sato T, Kondo Y. Simple and low-cost tabletop NMR system for chemical-shift-resolution spectra measurements. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 294:128-132. [PMID: 30036813 DOI: 10.1016/j.jmr.2018.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/08/2018] [Accepted: 07/06/2018] [Indexed: 05/03/2023]
Abstract
We have been working on developing a low-cost tabletop NMR system. We reported that a field homogeneity as high as 50 ppm was achieved with a simple NMR magnet by employing two facing ferrite magnets with iron disks in between (Chonlathep et al., 2017). In this paper, we report two improvements added to our previous system: (1) an FPGA based signal processing unit to improve the S/N ratio and (2) a simple shimming mechanism to improve the field homogeneity. We obtained as high as 1 ppm field homogeneity in the best case. The signals from hydrogen nuclear spins in a methyl and carboxy group in acetic acid were resolved in NMR spectra.
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Affiliation(s)
- Y Hibino
- Graduate School of Science and Engineering Research, Kindai University, 577-8502 Higashi-Osaka, Japan.
| | - K Sugahara
- Graduate School of Science and Engineering Research, Kindai University, 577-8502 Higashi-Osaka, Japan; Department of Electronics and Engineering, Kindai University, 577-8502 Higashi-Osaka, Japan.
| | - Y Muro
- THAMWAY Co., Ltd, 417-0001 Fuji, Japan
| | - H Tanaka
- THAMWAY Co., Ltd, 417-0001 Fuji, Japan
| | - T Sato
- THAMWAY Co., Ltd, 417-0001 Fuji, Japan
| | - Y Kondo
- Graduate School of Science and Engineering Research, Kindai University, 577-8502 Higashi-Osaka, Japan; Department of Physics, Kindai University, 577-8502 Higashi-Osaka, Japan.
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