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Sibanda N, Pfukwa H, Bungu PE, Pasch H. Advanced tools for molecular characterization of bio-based and biodegradable polymers. Anal Bioanal Chem 2024; 416:3665-3675. [PMID: 38517490 PMCID: PMC11180630 DOI: 10.1007/s00216-024-05255-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/08/2024] [Accepted: 03/12/2024] [Indexed: 03/24/2024]
Abstract
Bio-based and biodegradable materials play a vital role in a sustainable and green economy. These materials must exhibit properties that are similar to or better than the properties of oil- or coal-based materials and require sophisticated synthesis technologies and detailed knowledge of structure-property correlations. For comprehensive molecular structure elucidation, advanced analytical methods, including coupled and hyphenated techniques that combine advanced fractionation and information-rich spectroscopic detectors, are an indispensable tool. One important tool for fractionating complex polymers regarding molecular size is size exclusion chromatography. For fractionating polymers with regard to chemical composition, solvent (or temperature) gradient HPLC has been developed. The combination of different liquid chromatography methods in comprehensive two-dimensional HPLC setups is another important tool. Today, a toolbox of HPLC methods is in place that enables the fractionation of complex bio-based and biodegradable polymers according to the most important molecular parameters including molecular size, composition, functionality, and branching. Here, an overview of the different techniques and some major applications is presented. Some representative developments in the field are discussed, and different techniques, experimental protocols, and applications are highlighted.
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Affiliation(s)
- Ndumiso Sibanda
- Department of Chemistry and Polymer Science, University of Stellenbosch, Stellenbosch, 7602, South Africa
| | - Helen Pfukwa
- Department of Chemistry and Polymer Science, University of Stellenbosch, Stellenbosch, 7602, South Africa
| | - Paul Eselem Bungu
- Department of Correlative Characterization, Institute of Functional Materials for Sustainability, Helmholtz Center Hereon, Kantstrasse 55, 14513, Teltow, Germany
| | - Harald Pasch
- Department of Correlative Characterization, Institute of Functional Materials for Sustainability, Helmholtz Center Hereon, Kantstrasse 55, 14513, Teltow, Germany.
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2
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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.
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Affiliation(s)
- Sarah L Draper
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand
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3
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Wouters B, Miggiels P, Bezemer R, van der Cruijsen EA, van Leeuwen E, Gauvin J, Houben K, Babu Sai Sankar Gupta K, Zuijdwijk P, Harms A, Carvalho de Souza A, Hankemeier T. Automated Segmented-Flow Analysis – NMR with a Novel Fluoropolymer Flow Cell for High-Throughput Screening. Anal Chem 2022; 94:15350-15358. [DOI: 10.1021/acs.analchem.2c03038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bert Wouters
- Metabolomics and Analytics Centre, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, 2333 CCLeiden, The Netherlands
| | - Paul Miggiels
- Metabolomics and Analytics Centre, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, 2333 CCLeiden, The Netherlands
| | - Roland Bezemer
- DSM Biotechnology Center, Alexander Fleminglaan 1, 2613 AXDelft, The Netherlands
| | | | - Erik van Leeuwen
- DSM Biotechnology Center, Alexander Fleminglaan 1, 2613 AXDelft, The Netherlands
| | - John Gauvin
- DSM Biotechnology Center, Alexander Fleminglaan 1, 2613 AXDelft, The Netherlands
| | - Klaartje Houben
- DSM Biotechnology Center, Alexander Fleminglaan 1, 2613 AXDelft, The Netherlands
| | | | - Paul Zuijdwijk
- DSM Biotechnology Center, Alexander Fleminglaan 1, 2613 AXDelft, The Netherlands
| | - Amy Harms
- Metabolomics and Analytics Centre, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, 2333 CCLeiden, The Netherlands
| | | | - Thomas Hankemeier
- Metabolomics and Analytics Centre, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, 2333 CCLeiden, The Netherlands
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Matz M, Botha C, Beskers T, Wilhelm M. Fourier transformation liquid chromatography: increasing sensitivity by a factor of 50. Analyst 2022; 147:1199-1212. [DOI: 10.1039/d1an02298a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To turn liquid chromatography into a Fourier transformation technique a continuous sinusoidal sample concentration profile is developed, which increases the sensitivity. The analytes can be characterized by evaluating the phase angle and magnitude.
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Affiliation(s)
- Markus Matz
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, Engesserstraße 18, 76131 Karlsruhe, Germany
| | - Carlo Botha
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, Engesserstraße 18, 76131 Karlsruhe, Germany
| | - Timo Beskers
- PSS Polymer Standards Service GmbH, In der Dalheimer Wiese 5, 55023 Mainz, Germany
| | - Manfred Wilhelm
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry, Engesserstraße 18, 76131 Karlsruhe, Germany
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Singh SM, Furman R, Singh RK, Balakrishnan G, Chennamsetty N, Tao L, Li Z. Size exclusion chromatography for the characterization and quality control of biologics. J LIQ CHROMATOGR R T 2021. [DOI: 10.1080/10826076.2021.1979582] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Surinder M. Singh
- Analytical Development and Attribute Sciences, New Brunswick, NJ, USA
| | - Ran Furman
- Analytical Development and Attribute Sciences, New Brunswick, NJ, USA
| | - Rajesh K. Singh
- Analytical Development and Attribute Sciences, New Brunswick, NJ, USA
| | | | | | - Li Tao
- Analytical Development and Attribute Sciences, New Brunswick, NJ, USA
| | - Zhengjian Li
- Analytical Development and Attribute Sciences, New Brunswick, NJ, USA
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Heck M, Botha C, Wilhelm M, Hirschberg V. One-Pot Synthesis of Alternating (Ultra-High Molecular Weight) Multiblock Copolymers via a Combination of Anionic Polymerization and Polycondensation. Macromol Rapid Commun 2021; 42:e2100448. [PMID: 34528318 DOI: 10.1002/marc.202100448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/09/2021] [Indexed: 12/29/2022]
Abstract
This article presents a fast, straightforward synthesis approach to polymerize alternating multiblock copolymers, ultra-high molecular weight (UHMW) (homo)polymers as well as precursors for complex macromolecular topologies such as comb or barbwire architectures. The one-pot synthesis strategy proposed in this work is based on anionic polymerization via a bifunctional initiator and the subsequent linking of macro dianions with a bifunctional linker, additionally overcoming the limitations associated with the monomer reactivity. Thus, the synthetic route guarantees the repeating size of polymer blocks and an equal distribution of functional groups in precursors for complex topologies. Dianions of polystyrene (PS), polyisoprene-b-polystyrene-b-polyisoprene, and poly-2-vinylpyridine-b-polystyrene-b-poly-2-vinylpyridine are linked with α , α ' -dibromo-para-xylene to UHMW and multiblock copolymers. Multiblock copolymers with on average up to 50 well-defined alternating A and B blocks are accessible within 15 min.
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Affiliation(s)
- Matthias Heck
- Institute for Technical Chemistry and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 18, 76131 Karlsruhe, Germany
| | - Carlo Botha
- Institute for Technical Chemistry and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 18, 76131 Karlsruhe, Germany
| | - Manfred Wilhelm
- Institute for Technical Chemistry and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 18, 76131 Karlsruhe, Germany
| | - Valerian Hirschberg
- Institute for Technical Chemistry and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstraße 18, 76131 Karlsruhe, Germany
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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.
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Peters R, Pirok B, Mengerink Y. Molecular Correlative Material Characterization: Advantages for Polymer Analysis Using Liquid Chromatography. LCGC EUROPE 2021. [DOI: 10.56530/lcgc.eu.ez6278j8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This article discusses innovation around the molecular structure of polymeric materials—an indispensable part of modern society—with a specific focus on sustainability. This field of research, so-called molecular correlative material characterization (MCMC), will enhance the transition into new sustainable functional copolymers.
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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).
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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.
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van Beek TA. Low-field benchtop NMR spectroscopy: status and prospects in natural product analysis †. PHYTOCHEMICAL ANALYSIS : PCA 2021; 32:24-37. [PMID: 31989704 DOI: 10.1002/pca.2921] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/14/2019] [Accepted: 12/28/2019] [Indexed: 06/10/2023]
Abstract
INTRODUCTION Since a couple of years, low-field (LF) nuclear magnetic resonance (NMR) spectrometers (40-100 MHz) have re-entered the market. They are used for various purposes including analyses of natural products. Similar to high-field instruments (300-1200 MHz), modern LF instruments can measure multiple nuclei and record two-dimensional (2D) NMR spectra. OBJECTIVE To review the commercial availability as well as applications, advantages, limitations, and prospects of LF-NMR spectrometers for the purpose of natural products analysis. METHOD Commercial LF instruments were compared. A literature search was performed for articles using and discussing modern LF-NMR. Next, the articles relevant to natural products were read and summarised. RESULTS Seventy articles were reviewed. Most appeared in 2018 and 2019. Low costs and ease of operation are most often mentioned as reasons for using LF-NMR. CONCLUSION As the spectral resolution of LF instruments is limited, they are not used for structure elucidation of new natural products but rather applied for quality control (QC), forensics, food and health research, process control and teaching. Chemometric data handling is valuable. LF-NMR is a rapidly developing niche and new instruments keep being introduced.
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Affiliation(s)
- Teris André van Beek
- Laboratory of Organic Chemistry, Wageningen University, Stippeneng 4, WE Wageningen, The Netherlands
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Meunier DM, Wade JH, Janco M, Cong R, Gao W, Li Y, Mekap D, Wang G. Recent Advances in Separation-Based Techniques for Synthetic Polymer Characterization. Anal Chem 2020; 93:273-294. [DOI: 10.1021/acs.analchem.0c04352] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- David M. Meunier
- Core R&D, Analytical Science, The Dow Chemical Company, Midland, Michigan 48640, United States
| | - James H. Wade
- Core R&D, Analytical Science, The Dow Chemical Company, Midland, Michigan 48640, United States
| | - Miroslav Janco
- Core R&D, Analytical Science, The Dow Chemical Company, Collegeville, Pennsylvania 19426, United States
| | - Rongjuan Cong
- Packaging and Specialty Plastics, Characterization, The Dow Chemical Company, Lake Jackson, Texas 77566, United States
| | - Wei Gao
- Core R&D, Analytical Science, The Dow Chemical Company, Collegeville, Pennsylvania 19426, United States
| | - Yongfu Li
- Core R&D, Analytical Science, The Dow Chemical Company, Midland, Michigan 48640, United States
| | - Dibyaranjan Mekap
- Packaging and Specialty Plastics, Characterization, Dow Benelux, 4542 NM Terneuzen, The Netherlands
| | - Grace Wang
- School of Cinematic Arts, University of Southern California, Los Angeles, California 90089, United States
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Day IJ. Matrix-assisted DOSY. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2020; 116:1-18. [PMID: 32130955 DOI: 10.1016/j.pnmrs.2019.09.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/30/2019] [Accepted: 09/01/2019] [Indexed: 06/10/2023]
Abstract
The analysis of mixtures by NMR spectroscopy is challenging. Diffusion-ordered NMR spectroscopy enables a pseudo-separation of species based on differences in their translational diffusion coefficients. Under the right circumstances, this is a powerful technique; however, when molecules diffuse at similar rates separation in the diffusion dimension can be poor. In addition, spectral overlap also limits resolution and can make interpretation challenging. Matrix-assisted diffusion NMR seeks to improve resolution in the diffusion dimension by utilising the differential interaction of components in the mixture with an additive to the solvent. Tuning these matrix-analyte interactions allows the diffusion resolution to be optimised. This review presents the background to matrix-assisted diffusion experiments, surveys the wide range of matrices employed, including chromatographic stationary phases, surfactants and polymers, and demonstrates the current state of the art.
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Affiliation(s)
- Iain J Day
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QJ, UK.
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Vrijsen JH, Thomlinson IA, Levere ME, Lyall CL, Davidson MG, Hintermair U, Junkers T. Online tracing of molecular weight evolution during radical polymerization via high-resolution FlowNMR spectroscopy. Polym Chem 2020. [DOI: 10.1039/d0py00475h] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High-resolution FlowNMR was coupled to a continuous flow reactor to monitor polymer molecular weight evolution online by diffusion ordered NMR spectroscopy.
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Affiliation(s)
- Jeroen H. Vrijsen
- Hasselt University
- 3500 Hasselt
- Belgium
- Polymer Reaction Design Group
- School of Chemistry
| | - Isabel A. Thomlinson
- Centre for Sustainable and Circular Technologies
- University of Bath
- Bath BA2 7AY
- UK
| | - Martin E. Levere
- Dynamic Reaction Monitoring Facility
- University of Bath
- Bath BA2 7AY
- UK
| | | | - Matthew G. Davidson
- Centre for Sustainable and Circular Technologies
- University of Bath
- Bath BA2 7AY
- UK
| | - Ulrich Hintermair
- Centre for Sustainable and Circular Technologies
- University of Bath
- Bath BA2 7AY
- UK
- Dynamic Reaction Monitoring Facility
| | - Tanja Junkers
- Hasselt University
- 3500 Hasselt
- Belgium
- Polymer Reaction Design Group
- School of Chemistry
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14
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Kinetics of RAFT polymerization and copolymerization of vinyl monomers by size exclusion chromatography. Eur Polym J 2020. [DOI: 10.1016/j.eurpolymj.2019.109356] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Rubens M, Van Herck J, Junkers T. Automated Polymer Synthesis Platform for Integrated Conversion Targeting Based on Inline Benchtop NMR. ACS Macro Lett 2019; 8:1437-1441. [PMID: 35651185 DOI: 10.1021/acsmacrolett.9b00767] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
An automated polymer synthesis platform based on an inline low-field nuclear magnetic resonance spectrometer is developed. Flow chemistry and automated inline analyses are an excellent combination for automated kinetic screening and for self-optimizing reactions with programmable conversion targeting. By monitoring monomer conversion over a continuous range of reactor residence times, the platform is able to construct kinetic profiles of polymerizations in an accurate and efficient way. The machine-assisted self-optimization routine allows the reaction to be stopped at any given preselected conversion, giving rise to unprecedented reproducibility in polymer synthesis.
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Affiliation(s)
- Maarten Rubens
- Polymer Reaction Design Group, School of Chemistry, Monash University, 19 Rainforest Walk, Clayton, Victoria 3800, Australia
- Institute for Materials Research, Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
| | - Joren Van Herck
- Polymer Reaction Design Group, School of Chemistry, Monash University, 19 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - Tanja Junkers
- Polymer Reaction Design Group, School of Chemistry, Monash University, 19 Rainforest Walk, Clayton, Victoria 3800, Australia
- Institute for Materials Research, Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
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