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Lee H, Cho J, Jin M, Lee JH, Lee C, Kim J, Lee J, Shin JC, Yoo J, Lee E, Kim YS. Electrochemical Analysis of Ion Effects on Electrolyte-Gated Synaptic Transistor Characteristics. ACS NANO 2024. [PMID: 38324887 DOI: 10.1021/acsnano.3c10082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Electrolyte-gated transistors (EGTs) are promising candidates as artificial synapses owing to their precise conductance controllability, quick response times, and especially their low operating voltages resulting from ion-assisted signal transmission. However, it is still vague how ion-related physiochemical elements and working mechanisms impact synaptic performance. Here, to address the unclear correlations, we suggest a methodical approach based on electrochemical analysis using poly(ethylene oxide) EGTs with three alkali ions: Li+, Na+, and K+. Cyclic voltammetry is employed to identify the kind of electrochemical reactions taking place at the channel/electrolyte interface, which determines the nonvolatile memory functionality of the EGTs. Additionally, using electrochemical impedance spectroscopy and qualitative analysis of electrolytes, we confirm that the intrinsic properties of electrolytes (such as crystallinity, solubility, and ion conductivity) and ion dynamics ultimately define the linearity/symmetricity of conductance modulation. Through simple but systematic electrochemical analysis, these results offer useful insights for the selection of components for high-performing artificial synapses.
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Affiliation(s)
- Haeyeon Lee
- Department of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jinil Cho
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Minho Jin
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jae Hak Lee
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
- Samsung Display Company, Ltd., 1 Samsung-ro, Giheung-gu, Yongin-si, Gyeonggi-do 17113, Republic of Korea
| | - Chan Lee
- Department of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jiyeon Kim
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jiho Lee
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jong Chan Shin
- Department of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
| | - Jeeyoung Yoo
- School of Energy Engineering, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Eungkyu Lee
- Department of Electronic Engineering, Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Youn Sang Kim
- Department of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, Republic of Korea
- Advanced Institutes of Convergence Technology, 145 Gwanggyo-ro, Yeongtong-gu, Suwon 16229, Republic of Korea
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Muyizere T, Mukiza J. Progress on the development of a metal salt-assisted ionization source for the mass spectrometric analysis of polymers. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2022; 14:2803-2819. [PMID: 35848110 DOI: 10.1039/d2ay00724j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The mass spectrometric analysis of polymers has been addressed as a challenging research topic due to poor ionization and complicated analysis using conventional mass spectrometry. The ionization source has demonstrated a promising future in rapid mass spectrometric analysis. Soft ionization techniques, such as electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) are the most ionization sources appeared to be a powerful tools for polymer characterization when combined with MS. However, they always need metal salts to be introduced during the ionization protocol for polymers due to the crucial role played by their ions (cations and anions). The current review focuses on the progress in the development of metal ion-assisted-ionization sources for the mass spectrometric analysis of polymers. Different ionization systems are comprehensively reviewed. The application of metal ion-assisted ESI, nanoESI, PSI, and MALDI-MS for polymer sample analyses is systematically discussed. The future research trends and challenges in this cutting-edge research field are summarized. It also aims to provide the current state-of-the-art of metal salts as a platform for ionization systems for the mass spectrometric characterization of polymers and offers the current challenges and perspectives on the promising future to improve analytical performance in this field. Finally, this mini-review provides a comprehensive handbook to researchers from different research backgrounds wishing to work in this area.
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Affiliation(s)
- Theoneste Muyizere
- University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100039, China
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology, No. 11 Beiyitiao, Zhongguancun, 100190 Beijing, China.
| | - Janvier Mukiza
- Rwanda Food and Drugs Authority, Kigali 1948, Rwanda.
- School of Education, College of Education, University of Rwanda, P. O. BOX 55, Rwamagana, Rwanda
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Investigation of fragmentation behaviors of steroidal drugs with Li+, Na+, K+ adducts by tandem mass spectrometry aided with computational analysis. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.103939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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Conway U, Warren AD, Arthur CJ, Gates PJ. A study of the application of graphite MALDI to the analysis of short-chain polyethylene glycols. Polym Chem 2021. [DOI: 10.1039/d0py01493a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
MALDI-MS using colloidal graphite matrix doped with lithium chloride for the successful analysis of low molecular weight polymers.
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Affiliation(s)
- Ulric Conway
- School of Chemistry
- University of Bristol
- Bristol
- UK
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Aloui I, Legros V, Giuliani A, Buchmann W. Synchrotron UV photoactivation of trapped sodiated ions produced from poly(ethylene glycol) by electrospray ionization. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34 Suppl 2:e8773. [PMID: 32115839 DOI: 10.1002/rcm.8773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 02/25/2020] [Accepted: 02/28/2020] [Indexed: 06/10/2023]
Abstract
RATIONALE By taking advantage of the gas-phase decompositions of polymer ions, tandem mass spectrometry of polymers allows us to obtain more accurate structural information than from a simple mass measurement. Applied to a model polymer, the goal of this work was to evaluate the performances of an activation technique based on ultraviolet (UV) irradiation, as an alternative to conventional collisional activation. METHODS Sodiated poly(ethylene glycol) produced by electrospray ionization was isolated in a linear ion trap, then submitted to synchrotron UV irradiation over a range of wavelengths (52 to 248 nm). Fragmentation pathways resulting from UV photoactivation were investigated. The proposed mechanisms take into account: (i) the comparison with collision-induced dissociation (CID) product ions, (ii) the effect of wavelength-tunable UV activation, and (iii) deuterium-labeling and various other complementary experiments. For the highest molecular weight compounds, ion mobility spectrometry was used before UV photoactivation. RESULTS Synchrotron UV irradiation can induce dissociation of poly(ethylene glycol) sodiated ions without the requirement of the presence of a specific chromophore, if the photon energy is above 10 eV. UV photoactivation of poly(ethylene glycol) ions can yield fragmentations that differ from those in classical low-energy CID, especially from higher masses (>4000 g mol-1 ). A successful coupling of UV photoactivation with ion mobility pre-filtering was presented. CONCLUSIONS UV activation combined or not with pre-filtering ion mobility is a promising alternative approach for the structural characterization of polymers. UV synchrotron radiation with a tunable wavelength was a great opportunity to study the effect of the photon energy, and to probe the mechanisms of ion decomposition from poly(ethylene glycol).
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Affiliation(s)
- Inès Aloui
- Université Paris-Saclay, Univ Evry, CNRS, CEA, LAMBE, 91025, Evry, France
| | - Véronique Legros
- Université Paris-Saclay, Univ Evry, CNRS, CEA, LAMBE, 91025, Evry, France
| | - Alexandre Giuliani
- Disco Beamline, Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, 91192, Gif-sur-Yvette, France
- UAR1008, CEPIA, INRA, Rue de la Géraudière, F-44316, Nantes, France
| | - William Buchmann
- Université Paris-Saclay, Univ Evry, CNRS, CEA, LAMBE, 91025, Evry, France
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Grossert JS, Melanson JE, Ramaley L. Fragmentation Pathways of Cationized, Saturated, Short-Chain Triacylglycerols: Lithiated and Sodiated Tripropanoyl- and Trihexanoylglycerol. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:34-46. [PMID: 32881521 DOI: 10.1021/jasms.9b00046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Many methods, often depending on tandem mass spectrometry, have been developed for analysis of complex mixtures of triacylglycerols (TAGs), especially in clinical diagnostics and food authentication. Understanding the fragmentation mechanisms of cationized TAGs has proved problematic. To obtain a better understanding of viable mechanisms, detailed studies including double- and triple-stage tandem mass spectrometry were made using electrospray ionization on lithiated and sodiated tripropanoyl- and trihexanoylglycerols. Density functional theory computations, including a functional parameterized for van der Waals interactions, were used to correlate computed energies with mass spectra. Losses of both a neutral salt and a neutral acid corresponding to a glycerol side chain were observed as major product ions in MS2 experiments. Signal intensities at low collision energies correlated well with computed energies. However, an important difference between the lithiated and sodiated ions was the appearance of the sodium cation as a major fragmentation product. Computations on the product ions resulting from the loss of a neutral acid indicated multiple structures for the lithiated ions but mainly a single structure for the sodiated ions. The lithiated product ions could be fragmented further (pseudo-MS3) to give additional structural information, whereas the sodiated ions gave only m/z 23. The longer chain TAG, while giving a much less intense mass spectrum than the shorter chain TAG, gave comparable MS2 and MS3 product ion spectra. Taken together, the spectral and computational work described herein offer a new and detailed pathway for collision-induced fragmentation of lithiated and sodiated saturated TAGs.
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Affiliation(s)
- J Stuart Grossert
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. Box 15000, Halifax, NS, Canada B3H 4R2
| | - Jeremy E Melanson
- Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, ON, Canada K1A 0R6
| | - Louis Ramaley
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. Box 15000, Halifax, NS, Canada B3H 4R2
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Muyizere T, Zheng Y, Liu H, Zhao J, Li J, Lu X, Austin DE, Zhang Z. Metal salt assisted electrospray ionization mass spectrometry for the soft ionization of GAP polymers in negative ion mode. Analyst 2019; 145:34-45. [PMID: 31755893 DOI: 10.1039/c9an01887e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Glycidyl azide polymers (GAP) are one of the most important energetic polymers, but it is still a challenge to elucidate their structures using mass spectrometry due to their fragility upon ionization. Herein we developed a soft metal salt assisted electrospray ionization (MSAESI) to characterize directly GAP polymers using mass spectrometry. This technique combines paper spray ionization and the complexing effect of anions from metal salts with GAP in the negative ion mode to softly ionize GAP polymers prior to mass spectrometry analysis. The effects of experimental parameters (e.g., ion mode, applied voltage, and type and concentration of metal salts) have been investigated in detail. In contrast to the positive ion mode, a softer ionization was observed for GAP polymers when the negative ion mode was applied. The radius and average charge of cations and anions in metal salts were found to play crucial roles in determining the performance of the MSAESI analysis of GAP. For a given charge number, a smaller radius of cations favored the soft ionization of GAP polymers (e.g., Na+ > K+ > Rb+), whereas a larger radius of anions led to a preferred performance (e.g., F- < Cl- < Br- < I-) due to variation in dissolution ability. For anions with multiple charges, the ones with fewer charges gave a more favorable ionization to the GAP sample because of their better complexing to GAP molecules than those with more charges in the structure of anions (e.g., NO3- > SO42- > PO43-). According to the experimental observation and evidence from mass spectrometry, we proposed the plausible electrospray mechanisms of MSAESI for GAP analysis with the involvement of metal salts. Moreover, the developed protocol has been applied successfully to the analysis of various GAP samples, and works for other types of sources such as nanoelectrospray ionization.
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Affiliation(s)
- Theoneste Muyizere
- School of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an 710065, China.
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A Sensitive LC-MS/MS Method for Palytoxin Using Lithium Cationization. Toxins (Basel) 2018; 10:toxins10120537. [PMID: 30558165 PMCID: PMC6316396 DOI: 10.3390/toxins10120537] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 12/10/2018] [Accepted: 12/11/2018] [Indexed: 12/31/2022] Open
Abstract
Palytoxin (PlTX) and analogues are produced by certain dinoflagellates, sea anemones, corals and cyanobacteria. PlTX can accumulate in the food chain and when consumed it may cause intoxication with symptoms like myalgia, weakness, fever, nausea, and vomiting. The analysis of PlTXs is challenging, and because of the large molecular structure, it is difficult to develop a sensitive and selective liquid chromatography-mass spectrometry (LC-MS/MS) method. In this work, an LC-MS/MS method was developed to analyse PlTXs with use of lithium iodine and formic acid as additives in the mobile phase. For method development, initially, LC-hrMS was used to accurately determine the elemental composition of the precursor and product ions. The main adduct formed was [M + H + 2Li]3+. Fragments were identified with LC-hrMS and these were incorporated in the LC-MS/MS method. A method of 10 min was developed and a solid phase extraction clean-up procedure was optimised for shellfish matrix. The determined limits of detection were respectively 8 and 22 µg PlTX kg-1 for mussel and oyster matrix. Oysters gave a low recovery of approximately 50% for PlTX during extraction. The method was successfully in-house validated, repeatability had a relative standard deviation less than 20% (n = 5) at 30 µg PlTX kg-1 in mussel, cockle, and ensis, and at 60 µg PlTX kg-1 in oyster.
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Hong A, Lee HH, Heo CE, Cho Y, Kim S, Kang D, Kim HI. Distinct Fragmentation Pathways of Anticancer Drugs Induced by Charge-Carrying Cations in the Gas Phase. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:628-637. [PMID: 27981443 DOI: 10.1007/s13361-016-1559-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 10/24/2016] [Accepted: 10/31/2016] [Indexed: 06/06/2023]
Abstract
With the growth of the pharmaceutical industry, structural elucidation of drugs and derivatives using tandem mass spectrometry (MS2) has become essential for drug development and pharmacokinetics studies because of its high sensitivity and low sample requirement. Thus, research seeking to understand fundamental relationships between fragmentation patterns and precursor ion structures in the gas phase has gained attention. In this study, we investigate the fragmentation of the widely used anticancer drugs, doxorubicin (DOX), vinblastine (VBL), and vinorelbine (VRL), complexed by a singly charged proton or alkali metal ion (Li+, Na+, K+) in the gas phase. The drug-cation complexes exhibit distinct fragmentation patterns in tandem mass spectra as a function of cation size. The trends in fragmentation patterns are explicable in terms of structures derived from ion mobility mass spectrometry (IM-MS) and theoretical calculations. Graphical Abstract ᅟ.
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Affiliation(s)
- Areum Hong
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, Seoul, 02841, Republic of Korea
- Division of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
| | - Hong Hee Lee
- Division of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
| | - Chae Eun Heo
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, Seoul, 02841, Republic of Korea
| | - Yunju Cho
- Green-Nano Materials Research Center, Daegu, 41566, Republic of Korea
| | - Sunghwan Kim
- Green-Nano Materials Research Center, Daegu, 41566, Republic of Korea
- Department of Chemistry, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Dukjin Kang
- Division of Metrology for Quality of Life, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
| | - Hugh I Kim
- Department of Chemistry, Research Institute for Natural Sciences, Korea University, Seoul, 02841, Republic of Korea.
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Lee HH, Hong A, Cho Y, Kim S, Kim WJ, Kim HI. Structural Characterization of Anticancer Drug Paclitaxel and Its Metabolites Using Ion Mobility Mass Spectrometry and Tandem Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:329-338. [PMID: 26466599 DOI: 10.1007/s13361-015-1280-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 09/15/2015] [Accepted: 09/18/2015] [Indexed: 06/05/2023]
Abstract
Paclitaxel (PTX) is a popular anticancer drug used in the treatment of various types of cancers. PTX is metabolized in the human liver by cytochrome P450 to two structural isomers, 3′-p-hydroxypaclitaxel (3p-OHP) and 6α-hydroxypaclitaxel (6α-OHP). Analyzing PTX and its two metabolites, 3p-OHP and 6α-OHP, is crucial for understanding general pharmacokinetics, drug activity, and drug resistance. In this study, electrospray ionization ion mobility mass spectrometry (ESI-IM-MS) and collision induced dissociation (CID) are utilized for the identification and characterization of PTX and its metabolites. Ion mobility distributions of 3p-OHP and 6α-OHP indicate that hydroxylation of PTX at different sites yields distinct gas phase structures. Addition of monovalent alkali metal and silver metal cations enhances the distinct dissociation patterns of these structural isomers. The differences observed in the CID patterns of metalated PTX and its two metabolites are investigated further by evaluating their gas-phase structures. Density functional theory calculations suggest that the observed structural changes and dissociation pathways are the result of the interactions between the metal cation and the hydroxyl substituents in PTX metabolites.
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Affiliation(s)
- Hong Hee Lee
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea
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Lang J, Cayir M, Walg SP, Di Martino-Fumo P, Thiel WR, Niedner-Schatteburg G. Intermetallic Competition in the Fragmentation of Trimetallic Au-Zn-Alkali Complexes. Chemistry 2016; 22:2345-55. [PMID: 26785330 DOI: 10.1002/chem.201504093] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Indexed: 12/20/2022]
Affiliation(s)
- Johannes Lang
- Fachbereich Chemie and Forschungszentrum OPTIMAS; Technische Universität Kaiserslautern; 67663 Kaiserslautern Germany
| | - Merve Cayir
- Fachbereich Chemie and Forschungszentrum OPTIMAS; Technische Universität Kaiserslautern; 67663 Kaiserslautern Germany
| | - Simon P. Walg
- Fachbereich Chemie and Forschungszentrum OPTIMAS; Technische Universität Kaiserslautern; 67663 Kaiserslautern Germany
| | - Patrick Di Martino-Fumo
- Fachbereich Chemie and Forschungszentrum OPTIMAS; Technische Universität Kaiserslautern; 67663 Kaiserslautern Germany
| | - Werner R. Thiel
- Fachbereich Chemie and Forschungszentrum OPTIMAS; Technische Universität Kaiserslautern; 67663 Kaiserslautern Germany
| | - Gereon Niedner-Schatteburg
- Fachbereich Chemie and Forschungszentrum OPTIMAS; Technische Universität Kaiserslautern; 67663 Kaiserslautern Germany
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Qi Y, Volmer DA. Structural analysis of small to medium-sized molecules by mass spectrometry after electron-ion fragmentation (ExD) reactions. Analyst 2016; 141:794-806. [PMID: 26725919 DOI: 10.1039/c5an02171e] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electron capture dissociation (ECD) is a tandem mass spectrometry (MS/MS) method that utilizes the interaction of ions and electrons. Its unique ability to preserve labile bonds distinguishes it from conventional threshold-based MS/MS methods, the most important of which is collision-induced dissociation (CID). During the last decade, ECD has opened up several new venues in protein analyses, for example top-down sequencing, identification of post-translational modifications, and characterization of protein-protein interactions. In recent years, a number of related dissociation techniques, so-called ExD techniques, particularly electron transfer dissociation (ETD), electron detachment dissociation (EDD), electron induced dissociation (EID), and negative electron transfer dissociation (NETD), have emerged and have extended the application range of ion-electron dissociations further. Importantly, ExD techniques have been applied beyond protein analyses, which is the focus of the current paper. This short introduction describes the application of ExD to small and medium-sized molecules and reviews important applications to natural products, biomedical compounds, synthetic molecules, crude oils, and environmental toxins.
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Affiliation(s)
- Yulin Qi
- Institute of Bioanalytical Chemistry, Saarland University, 66123 Saarbrücken, Germany.
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