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Gouilleux B, Moussallieh FM, Lesot P. Potential and performance of anisotropic 19F NMR for the enantiomeric analysis of fluorinated chiral active pharmaceutical ingredients. Analyst 2024; 149:3204-3213. [PMID: 38655746 DOI: 10.1039/d4an00237g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Controlling the enantiomeric purity of chiral drugs is of paramount importance in pharmaceutical chemistry. Isotropic 1H NMR spectroscopy involving chiral agents is a widely used method for discriminating enantiomers and quantifying their relative proportions. However, the relatively weak spectral separation of enantiomers (1H Δδiso(R, S)) in frequency units at low and moderate magnetic fields, as well as the lack of versatility of a majority of those agents with respect to different chemical functions, may limit the general use of this approach. In this article, we investigate the analytical potential of 19F NMR in anisotropic chiral media for the enantiomeric analysis of fluorinated active pharmaceutical ingredients (API) via two residual anisotropic NMR interactions: the chemical shift anisotropy (19F-RCSA) and dipolar coupling ((19F-19F)-RDC). Lyotropic chiral liquid crystals (CLC) based on poly-γ-benzyl-L-glutamate (PBLG) show an interesting versatility and adaptability to enantiodiscrimination as illustrated for two chiral drugs, Flurbiprofen® (FLU) and Efavirenz® (EFA), which have very different chemical functions. The approach has been tested on a routine 300 MHz NMR spectrometer equipped with a standard probe (5 mm BBFO probe) in a high-throughput context (i.e., ≈10 s of NMR experiments) while the performance for enantiomeric excess (ee) measurement is evaluated in terms of trueness and precision. The limits of detection (LOD) determined were 0.17 and 0.16 μmol ml-1 for FLU and EFA, respectively, allow working in dilute conditions even with such a short experimental duration. The enantiodiscrimination capabilities are also discussed with respect to experimental features such as CLC composition and temperature.
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Affiliation(s)
- Boris Gouilleux
- Université Paris-Saclay, UFR d'Orsay, RMN en Milieu Orienté, ICMMO, UMR CNRS 8182, Bât. HM1, 17-19, Avenue des Sciences, 91400, Orsay, France
| | - François-Marie Moussallieh
- Université Paris-Saclay, UFR d'Orsay, RMN en Milieu Orienté, ICMMO, UMR CNRS 8182, Bât. HM1, 17-19, Avenue des Sciences, 91400, Orsay, France
| | - Philippe Lesot
- Université Paris-Saclay, UFR d'Orsay, RMN en Milieu Orienté, ICMMO, UMR CNRS 8182, Bât. HM1, 17-19, Avenue des Sciences, 91400, Orsay, France
- Centre National de la Recherche Scientifique (CNRS), 3, Rue Michel Ange, F-75016 Paris, France.
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Huynh MT, Buchanan E, Chirayil S, Adebesin AM, Kovacs Z. StereoPHIP: Stereoselective Parahydrogen-Induced Polarization. Angew Chem Int Ed Engl 2023; 62:e202311669. [PMID: 37714818 PMCID: PMC10842948 DOI: 10.1002/anie.202311669] [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: 08/10/2023] [Revised: 09/14/2023] [Accepted: 09/15/2023] [Indexed: 09/17/2023]
Abstract
Parahydrogen-induced polarization (PHIP) followed by polarization transfer to 13 C is a rapidly developing technique for the generation of 13 C-hyperpolarized substrates. Chirality plays an essential role in living systems and differential metabolism of enantiomeric pairs of metabolic substrates is well documented. Inspired by asymmetric hydrogenation, here we report stereoPHIP, which involves the addition of parahydrogen to a prochiral substrate with a chiral catalyst followed by polarization transfer to 13 C spins. We demonstrate that parahydrogen could be rapidly added to the prochiral precursor to both enantiomers of lactic acid (D and L), with both the (R,R) and (S,S) enantiomers of a chiral rhodium(I) catalyst to afford highly 13 C-hyperpolarized (over 20 %) L- and D-lactate ester derivatives, respectively, with excellent stereoselectivity. We also show that the hyperpolarized 1 H signal decays obtained with the (R,R) and (S,S) catalysts were markedly different. StereoPHIP expands the scope of conventional PHIP to the production of 13 C hyperpolarized chiral substrates with high stereoselectivity.
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Affiliation(s)
- Mai T Huynh
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Emily Buchanan
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Sara Chirayil
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Adeniyi M Adebesin
- Department Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Zoltan Kovacs
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
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3
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Yang XL, Yang ZY, Shao R, Guan RF, Dong SL, Xie MH. Chiral MOF Derived Wearable Logic Sensor for Intuitive Discrimination of Physiologically Active Enantiomer. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2304046. [PMID: 37269216 DOI: 10.1002/adma.202304046] [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: 04/30/2023] [Revised: 12/12/2012] [Indexed: 06/04/2023]
Abstract
Chiral sensors have attracted growing interest due to their application in health monitoring. However, rational design of wearable logic chiral sensors remains a great challenge. In this work, a dual responsive chiral sensor RT@CDMOF is prepared through in situ self-assembly of chiral γ-cyclodextrin metal-organic framework (CDMOF), rhodamine 6G hydrazide (RGH), and tetracyanovinylindane (TCN). The embedded RGH and TCN inherit the chirality of host CDMOF, producing dual changes both in fluorescence and reflectance. RT@CDMOF is explored as a dual channel sensor for chiral discrimination of lactate enantiomers. Comprehensive mechanistic studies reveal the chiral binding process, and carboxylate dissociation is confirmed by impedance and solid-state 1 H nuclear magnetic resonance (NMR). A flexible membrane sensor is successfully fabricated based on RT@CDMOF for wearable health monitoring. Practical evaluation confirms the potential of fabricated membrane sensor in point-of-care health monitoring by indexing the exercise intensity. Based on above, a chiral IMPLICATION logic unit can be successfully achieved, demonstrating the promising potential of RT@CDMOF in design and assembly of novel smart devices. This work may open a new avenue to the rational design of logic chiral sensors for wearable health monitoring applications.
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Affiliation(s)
- Xiu-Li Yang
- Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng, 224051, P. R. China
| | - Zheng-Ying Yang
- Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng, 224051, P. R. China
| | - Rong Shao
- Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng, 224051, P. R. China
| | - Rong-Feng Guan
- Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng, 224051, P. R. China
| | - Su-Li Dong
- Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng, 224051, P. R. China
| | - Ming-Hua Xie
- Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng, 224051, P. R. China
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Tickner BJ, Platas-Iglesias C, Duckett SB, Angelovski G. In Situ Ternary Adduct Formation of Yttrium Polyaminocarboxylates Leads to Small Molecule Capture and Activation. Chemistry 2022; 28:e202201780. [PMID: 35853826 DOI: 10.1002/chem.202201780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Indexed: 01/07/2023]
Abstract
In this work the chemistry of yttrium complexes is exploited for small molecule capture and activation. Nuclear magnetic resonance (NMR) and density functional theory (DFT) studies were used to investigate the in situ formation of solution state ternary yttrium-acetate, yttrium-bicarbonate, and yttrium-pyruvate adducts with a range of polyaminocarboxylate chelates. These studies reveal that [Y(DO3A)(H2 O)2 ] (H3 DO3A - 1,4,7,10-tetraazacyclododecane-1,4,7-tricarboxylic acid) and [Y(EDTA)(H2 O)q ]- (H4 EDTA - ethylenediaminetetraacetic acid, q = 2 and 3) are able to form ternary adducts with bicarbonate and pyruvate. In the latter, unusual decarboxylation of pyruvate to form acetic acid and CO2 was observed and further studied using SABRE-hyperpolarised 13 C NMR (SABRE - signal amplification by reversible exchange) to provide information about the reaction timescale and lifetime of intermediates involved in this conversion. The work presented demonstrates that yttrium complexes can capture and activate small molecules, which may lead to novel and useful applications of this metal in catalysis and medical imaging.
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Affiliation(s)
- Ben J Tickner
- Centre for Hyperpolarisation in Magnetic Resonance, Department of Chemistry, University of York, Heslington, YO10 5NY, United Kingdom.,MR Neuroimaging agents, Max Planck Institute for Biological Cybernetics, Tübingen, 72076, Germany
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Química, Facultade de Ciencias, Universidade da Coruña, A Coruña, 15001, Spain
| | - Simon B Duckett
- Centre for Hyperpolarisation in Magnetic Resonance, Department of Chemistry, University of York, Heslington, YO10 5NY, United Kingdom
| | - Goran Angelovski
- MR Neuroimaging agents, Max Planck Institute for Biological Cybernetics, Tübingen, 72076, Germany.,Laboratory of Molecular and Cellular Neuroimaging, International Center for Primate Brain Research (ICPBR), Center for Excellence in Brain Science and Intelligence Technology (CEBSIT), Chinese Academy of Sciences (CAS), Shanghai, 200031, PR China
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Peluso P, Chankvetadze B. Recognition in the Domain of Molecular Chirality: From Noncovalent Interactions to Separation of Enantiomers. Chem Rev 2022; 122:13235-13400. [PMID: 35917234 DOI: 10.1021/acs.chemrev.1c00846] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
It is not a coincidence that both chirality and noncovalent interactions are ubiquitous in nature and synthetic molecular systems. Noncovalent interactivity between chiral molecules underlies enantioselective recognition as a fundamental phenomenon regulating life and human activities. Thus, noncovalent interactions represent the narrative thread of a fascinating story which goes across several disciplines of medical, chemical, physical, biological, and other natural sciences. This review has been conceived with the awareness that a modern attitude toward molecular chirality and its consequences needs to be founded on multidisciplinary approaches to disclose the molecular basis of essential enantioselective phenomena in the domain of chemical, physical, and life sciences. With the primary aim of discussing this topic in an integrated way, a comprehensive pool of rational and systematic multidisciplinary information is provided, which concerns the fundamentals of chirality, a description of noncovalent interactions, and their implications in enantioselective processes occurring in different contexts. A specific focus is devoted to enantioselection in chromatography and electromigration techniques because of their unique feature as "multistep" processes. A second motivation for writing this review is to make a clear statement about the state of the art, the tools we have at our disposal, and what is still missing to fully understand the mechanisms underlying enantioselective recognition.
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Affiliation(s)
- Paola Peluso
- Istituto di Chimica Biomolecolare ICB, CNR, Sede secondaria di Sassari, Traversa La Crucca 3, Regione Baldinca, Li Punti, I-07100 Sassari, Italy
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Avenue 3, 0179 Tbilisi, Georgia
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Botár R, Molnár E, Garda Z, Madarasi E, Trencsényi G, Kiss J, Kálmán FK, Tircsó G. Synthesis and characterization of a stable and inert MnII-based ZnII responsive MRI probe for molecular imaging of glucose stimulated zinc secretion (GSZS). Inorg Chem Front 2022. [DOI: 10.1039/d1qi00501d] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A ZnII responsive MnII-based MRI contrast agent, [Mn(PC2A-DPA)], has been synthesized, investigated and applied in imaging studies. It shows high stability and excellent inertness and can be used to visualize glucose triggered ZnII release by MRI.
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Affiliation(s)
- Richárd Botár
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
- Doctoral School of Chemistry, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - Enikő Molnár
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - Zoltán Garda
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - Enikő Madarasi
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
- Doctoral School of Chemistry, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - György Trencsényi
- Department of Medical Imaging, Division of Nuclear Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - János Kiss
- Department of Medical Imaging, Division of Nuclear Medicine, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - Ferenc K. Kálmán
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - Gyula Tircsó
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
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Suh EH, Geraldes CFGC, Chirayil S, Faubert B, Ayala R, DeBerardinis RJ, Sherry AD. Detection of glucose-derived D- and L-lactate in cancer cells by the use of a chiral NMR shift reagent. Cancer Metab 2021; 9:38. [PMID: 34742347 PMCID: PMC8571830 DOI: 10.1186/s40170-021-00267-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 08/25/2021] [Indexed: 01/04/2023] Open
Abstract
Background Excessive lactate production, a hallmark of cancer, is largely formed by the reduction of pyruvate via lactate dehydrogenase (LDH) to l-lactate. Although d-lactate can also be produced from glucose via the methylglyoxal pathway in small amounts, less is known about the amount of d-lactate produced in cancer cells. Since the stereoisomers of lactate cannot be distinguished by conventional 1H NMR spectroscopy, a chiral NMR shift reagent was used to fully resolve the 1H NMR resonances of d- and l-lactate. Methods The production of l-lactate from glucose and d-lactate from methylglyoxal was first demonstrated in freshly isolated red blood cells using the chiral NMR shift reagent, YbDO3A-trisamide. Then, two different cell lines with high GLO1 expression (H1648 and H 1395) were selected from a panel of over 80 well-characterized human NSCLC cell lines, grown to confluence in standard tissue culture media, washed with phosphate-buffered saline, and exposed to glucose in a buffer for 4 h. After 4 h, a small volume of extracellular fluid was collected and mixed with YbDO3A-trisamide for analysis by 1H NMR spectroscopy. Results A suspension of freshly isolated red blood cells exposed to 5mM glucose produced l-lactate as expected but very little d-lactate. To evaluate the utility of the chiral NMR shift reagent, methylglyoxal was then added to red cells along with glucose to stimulate the production of d-lactate via the glyoxalate pathway. In this case, both d-lactate and l-lactate were produced and their NMR chemical shifts assigned. NSCLC cell lines with different expression levels of GLO1 produced both l- and d-lactate after incubation with glucose and glutamine alone. A GLO1-deleted parental cell line (3553T3) showed no production of d-lactate from glucose while re-expression of GLO1 resulted in higher production of d-lactate. Conclusions The shift-reagent-aided NMR technique demonstrates that d-lactate is produced from glucose in NSCLC cells via the methylglyoxal pathway. The biological role of d-lactate is uncertain but a convenient method for monitoring d-lactate production could provide new insights into the biological roles of d- versus l-lactate in cancer metabolism. Supplementary Information The online version contains supplementary material available at 10.1186/s40170-021-00267-4.
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Affiliation(s)
- Eul Hyun Suh
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Carlos F G C Geraldes
- Department of Life Sciences and Coimbra Chemistry Center, Faculty of Science and Technology, University of Coimbra, 3000-393, Coimbra, Portugal.,CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, 3000-548, Coimbra, Portugal
| | - Sara Chirayil
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Brandon Faubert
- Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Raul Ayala
- School of Health Professions at Yvonne A. Ewell Townview Center, Dallas, TX, USA
| | - Ralph J DeBerardinis
- Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Pediatrics and Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - A Dean Sherry
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA. .,Department of Chemistry and Biochemistry, University of Texas at Dallas, Richardson, TX, USA. .,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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8
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Bai H, Chen L. Simultaneous separation of atenolol enantiomers and its acid/alkaline degradation impurities on mixed-mode chiral ligand exchange stationary phases. Chirality 2021; 33:710-721. [PMID: 34423466 DOI: 10.1002/chir.23353] [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: 05/15/2021] [Revised: 07/05/2021] [Accepted: 07/19/2021] [Indexed: 12/19/2022]
Abstract
Simultaneous separation of the enantiomer and impurities is a huge challenge for the quality control of the chiral drug. In this work, mixed-mode chiral ligand exchange stationary phases (CSPs) modified by octyl and sulfhydryl ligands were prepared by vapor deposition and click chemistry methods. Qualitative and quantitative determination of the prepared CSPs were achieved by Fourier transform infrared spectroscopy, solid-state 13 C CP/MAS NMR, and elemental analysis. The chiral resolution of CSPs was investigated through a comprehensively chromatographic evaluation of various racemates. Besides, the thermodynamic experiment was carried out to elucidate the contribution of hydrophobic ligand to the improvement of chiral recognition and selectivity. Atenolol and its degradation products were analyzed on the synthesized CSPs and compared with the commercial chiral column. A good separation of atenolol enantiomers from its acid and alkaline degradation impurities was simultaneously achieved on the C8 /L-Hypro CSP. This new CSP is expected to have more applications in the quality control of other chiral drugs.
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Affiliation(s)
- Hui Bai
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
| | - Lei Chen
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
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10
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Prasad S, Chandra A, Cavo M, Parasido E, Fricke S, Lee Y, D'Amone E, Gigli G, Albanese C, Rodriguez O, Del Mercato LL. Optical and magnetic resonance imaging approaches for investigating the tumour microenvironment: state-of-the-art review and future trends. NANOTECHNOLOGY 2021; 32:062001. [PMID: 33065554 DOI: 10.1088/1361-6528/abc208] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The tumour microenvironment (TME) strongly influences tumorigenesis and metastasis. Two of the most characterized properties of the TME are acidosis and hypoxia, both of which are considered hallmarks of tumours as well as critical factors in response to anticancer treatments. Currently, various imaging approaches exist to measure acidosis and hypoxia in the TME, including magnetic resonance imaging (MRI), positron emission tomography and optical imaging. In this review, we will focus on the latest fluorescent-based methods for optical sensing of cell metabolism and MRI as diagnostic imaging tools applied both in vitro and in vivo. The primary emphasis will be on describing the current and future uses of systems that can measure intra- and extra-cellular pH and oxygen changes at high spatial and temporal resolution. In addition, the suitability of these approaches for mapping tumour heterogeneity, and assessing response or failure to therapeutics will also be covered.
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Affiliation(s)
- Saumya Prasad
- Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy
| | - Anil Chandra
- Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy
| | - Marta Cavo
- Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy
| | - Erika Parasido
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
- Center for Translational Imaging, Georgetown University Medical Center, Washington, DC, United States of America
| | - Stanley Fricke
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
- Center for Translational Imaging, Georgetown University Medical Center, Washington, DC, United States of America
- Department of Radiology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Yichien Lee
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Eliana D'Amone
- Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy
| | - Giuseppe Gigli
- Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy
- Department of Mathematics and Physics 'Ennio De Giorgi', University of Salento, via Arnesano, 73100, Lecce, Italy
| | - Chris Albanese
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
- Center for Translational Imaging, Georgetown University Medical Center, Washington, DC, United States of America
- Department of Radiology, Georgetown University Medical Center, Washington, DC, United States of America
| | - Olga Rodriguez
- Department of Oncology, Georgetown University Medical Center, Washington, DC, United States of America
- Center for Translational Imaging, Georgetown University Medical Center, Washington, DC, United States of America
| | - Loretta L Del Mercato
- Institute of Nanotechnology, National Research Council (CNR-NANOTEC), c/o Campus Ecotekne, via Monteroni, 73100, Lecce, Italy
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Wydra K, Kobyłka MJ, Lis T, Ślepokura K, Lisowski J. Versatile Binding Modes of Chiral Macrocyclic Amine towards Rare Earth Ions. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000247] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Karol Wydra
- Department of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
| | - Michał J. Kobyłka
- Department of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
| | - Tadeusz Lis
- Department of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
| | - Katarzyna Ślepokura
- Department of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
| | - Jerzy Lisowski
- Department of Chemistry University of Wrocław 14 F. Joliot‐Curie 50‐383 Wrocław Poland
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Use of Large and Diverse Datasets for 1H NMR Serum Metabolic Profiling of Early Lactation Dairy Cows. Metabolites 2020; 10:metabo10050180. [PMID: 32366010 PMCID: PMC7281003 DOI: 10.3390/metabo10050180] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 01/05/2023] Open
Abstract
Most livestock metabolomic studies involve relatively small, homogenous populations of animals. However, livestock farming systems are non-homogenous, and large and more diverse datasets are required to ensure that biomarkers are robust. The aims of this study were therefore to (1) investigate the feasibility of using a large and diverse dataset for untargeted proton nuclear magnetic resonance (1H NMR) serum metabolomic profiling, and (2) investigate the impact of fixed effects (farm of origin, parity and stage of lactation) on the serum metabolome of early-lactation dairy cows. First, we used multiple linear regression to correct a large spectral dataset (707 cows from 13 farms) for fixed effects prior to multivariate statistical analysis with principal component analysis (PCA). Results showed that farm of origin accounted for up to 57% of overall spectral variation, and nearly 80% of variation for some individual metabolite concentrations. Parity and week of lactation had much smaller effects on both the spectra as a whole and individual metabolites (< 3% and < 20%, respectively). In order to assess the effect of fixed effects on prediction accuracy and biomarker discovery, we used orthogonal partial least squares (OPLS) regression to quantify the relationship between NMR spectra and concentrations of the current gold standard serum biomarker of energy balance, β-hydroxybutyrate (BHBA). Models constructed using data from multiple farms provided reasonably robust predictions of serum BHBA concentration (0.05 ≤ RMSE ≤ 0.18). Fixed effects influenced the results biomarker discovery; however, these impacts could be controlled using the proposed method of linear regression spectral correction.
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A New Class of Smart Gadolinium Contrast Agent for Tissue pH Probing Using Magnetic Resonance Imaging. Molecules 2020; 25:molecules25071513. [PMID: 32225079 PMCID: PMC7180778 DOI: 10.3390/molecules25071513] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/13/2020] [Accepted: 03/15/2020] [Indexed: 11/17/2022] Open
Abstract
Detecting tissue pH in vivo is extremely vital for medical diagnosis and formulation of treatment decisions. To this end, many investigations have been carried out to develop an accurate and efficient method of in vivo pH measurement. Most of the techniques developed so far suffer from inadequate accuracy, due to poor sensitivity at low concentration of the target or nonspecific interactions within the tissue matrix. To overcome these issues, we describe herein the development of a simple, yet reliable, way to estimate pH with high precision using a Gd(III)-DOTA-silyl-based acid-labile group as a pH-sensitive contrast agent with Magnetic Resonance Imaging (MRI). With this method, a change in T1 weighted image intensity of the newly developed pH-sensitive contrast is directly linked to the proton concentration in the media. As a result, we were able estimate the pH of the target with 95% reliability.
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Consolino L, Anemone A, Capozza M, Carella A, Irrera P, Corrado A, Dhakan C, Bracesco M, Longo DL. Non-invasive Investigation of Tumor Metabolism and Acidosis by MRI-CEST Imaging. Front Oncol 2020; 10:161. [PMID: 32133295 PMCID: PMC7040491 DOI: 10.3389/fonc.2020.00161] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 01/29/2020] [Indexed: 12/15/2022] Open
Abstract
Altered metabolism is considered a core hallmark of cancer. By monitoring in vivo metabolites changes or characterizing the tumor microenvironment, non-invasive imaging approaches play a fundamental role in elucidating several aspects of tumor biology. Within the magnetic resonance imaging (MRI) modality, the chemical exchange saturation transfer (CEST) approach has emerged as a new technique that provides high spatial resolution and sensitivity for in vivo imaging of tumor metabolism and acidosis. This mini-review describes CEST-based methods to non-invasively investigate tumor metabolism and important metabolites involved, such as glucose and lactate, as well as measurement of tumor acidosis. Approaches that have been exploited to assess response to anticancer therapies will also be reported for each specific technique.
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Affiliation(s)
- Lorena Consolino
- Department of Nanomedicines and Theranostics, Institute for Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany.,Department of Molecular Biotechnology and Health Sciences, Molecular Imaging Center, University of Torino, Turin, Italy
| | - Annasofia Anemone
- Department of Molecular Biotechnology and Health Sciences, Molecular Imaging Center, University of Torino, Turin, Italy
| | - Martina Capozza
- Department of Molecular Biotechnology and Health Sciences, Molecular Imaging Center, University of Torino, Turin, Italy
| | - Antonella Carella
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Turin, Italy
| | - Pietro Irrera
- University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Alessia Corrado
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Turin, Italy
| | - Chetan Dhakan
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Turin, Italy.,University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Martina Bracesco
- Department of Molecular Biotechnology and Health Sciences, Molecular Imaging Center, University of Torino, Turin, Italy
| | - Dario Livio Longo
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Turin, Italy
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15
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Rodríguez-Rodríguez A, Arnosa-Prieto Á, Brandariz I, Esteban-Gómez D, Platas-Iglesias C. Axial Ligation in Ytterbium(III) DOTAM Complexes Rationalized with Multireference and Ligand-Field ab Initio Calculations. J Phys Chem A 2020; 124:1362-1371. [DOI: 10.1021/acs.jpca.9b11683] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Aurora Rodríguez-Rodríguez
- Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Ángela Arnosa-Prieto
- Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Isabel Brandariz
- Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
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16
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He H, Zhao K, Xiao L, Zhang Y, Cheng Y, Wan S, Chen S, Zhang L, Zhou X, Liu K, Zhang H. Detection and Chiral Recognition of α‐Hydroxyl Acid through
1
H and CEST NMR Spectroscopy Using a Ytterbium Macrocyclic Complex. Angew Chem Int Ed Engl 2019; 58:18286-18289. [DOI: 10.1002/anie.201912072] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Haonan He
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Kelu Zhao
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Long Xiao
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of Sciences Wuhan 430071 China
| | - Yi Zhang
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Yi Cheng
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Sikang Wan
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Shizhen Chen
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of Sciences Wuhan 430071 China
| | - Lei Zhang
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
| | - Xin Zhou
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of Sciences Wuhan 430071 China
| | - Kai Liu
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Hongjie Zhang
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
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17
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He H, Zhao K, Xiao L, Zhang Y, Cheng Y, Wan S, Chen S, Zhang L, Zhou X, Liu K, Zhang H. Detection and Chiral Recognition of α‐Hydroxyl Acid through
1
H and CEST NMR Spectroscopy Using a Ytterbium Macrocyclic Complex. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201912072] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Haonan He
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Kelu Zhao
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Long Xiao
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of Sciences Wuhan 430071 China
| | - Yi Zhang
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Yi Cheng
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Sikang Wan
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Shizhen Chen
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of Sciences Wuhan 430071 China
| | - Lei Zhang
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
| | - Xin Zhou
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of Sciences Wuhan 430071 China
| | - Kai Liu
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
| | - Hongjie Zhang
- State Key Laboratory of Rare Earth Resource UtilizationChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China
- University of Science and Technology of China Hefei 230026 P. R. China
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18
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Goldenberg JM, Pagel MD. Assessments of tumor metabolism with CEST MRI. NMR IN BIOMEDICINE 2019; 32:e3943. [PMID: 29938857 PMCID: PMC7377947 DOI: 10.1002/nbm.3943] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/13/2018] [Accepted: 04/18/2018] [Indexed: 05/06/2023]
Abstract
Chemical exchange saturation transfer (CEST) is a relatively new contrast mechanism for MRI. CEST MRI exploits a specific MR frequency (chemical shift) of a molecule while generating an image with good spatial resolution using standard MRI techniques, combining the specificity of MRS with the spatial resolution of MRI. Many CEST MRI acquisition methods have been developed to improve analyses of tumor metabolism. GluCEST, CrCEST, and LATEST can map glutamate, creatine, and lactate, which are important metabolites involved in tumor metabolism. GlucoCEST MRI tracks the pharmacokinetics of glucose transport and cell internalization within tumors. CatalyCEST MRI detects enzyme catalysis that changes a substrate CEST agent. AcidoCEST MRI measures extracellular pH of the tumor microenvironment by exploiting a ratio of two pH-dependent CEST signals. This review describes each technique, the technical issues involved with CEST MRI and each specific technique, and the merits and challenges associated with applying each CEST MRI technique to study tumor metabolism.
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Affiliation(s)
- Joshua M. Goldenberg
- Department of Pharmaceutical Sciences, The University of Arizona, Tucson, AZ, USA
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Mark D. Pagel
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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19
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Abstract
This article aimed at reviewing the advances on the development of paramagnetic complexes used as chemical exchange saturation transfer agents in magnetic resonance imaging. This relatively new type of contrast opens new avenues in the development of MRI probes for molecular imaging, and coordination chemistry lies at the center of such advances. Strategies to detect important biomarkers such as pH, cations, anions, metabolites, enzyme, and O2 were described. The current challenges, limitations, and opportunities in this field of research were discussed.
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20
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Esteban-Gómez D, Büldt LA, Pérez-Lourido P, Valencia L, Seitz M, Platas-Iglesias C. Understanding the Optical and Magnetic Properties of Ytterbium(III) Complexes. Inorg Chem 2019; 58:3732-3743. [DOI: 10.1021/acs.inorgchem.8b03354] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas and Departamento de Química Fundamental, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Laura A. Büldt
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Paulo Pérez-Lourido
- Departamento de Química Inorgánica, Facultad de Ciencias, Universidade de Vigo, As Lagoas, Marcosende, 36310 Pontevedra, Spain
| | - Laura Valencia
- Departamento de Química Inorgánica, Facultad de Ciencias, Universidade de Vigo, As Lagoas, Marcosende, 36310 Pontevedra, Spain
| | - Michael Seitz
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas and Departamento de Química Fundamental, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
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21
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Ntziachristos V, Pleitez MA, Aime S, Brindle KM. Emerging Technologies to Image Tissue Metabolism. Cell Metab 2019; 29:518-538. [PMID: 30269982 DOI: 10.1016/j.cmet.2018.09.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/24/2018] [Accepted: 09/02/2018] [Indexed: 12/19/2022]
Abstract
Due to the implication of altered metabolism in a large spectrum of tissue function and disease, assessment of metabolic processes becomes essential in managing health. In this regard, imaging can play a critical role in allowing observation of biochemical and physiological processes. Nuclear imaging methods, in particular positron emission tomography, have been widely employed for imaging metabolism but are mainly limited by the use of ionizing radiation and the sensing of only one parameter at each scanning session. Observations in healthy individuals or longitudinal studies of disease could markedly benefit from non-ionizing, multi-parameter imaging methods. We therefore focus this review on progress with the non-ionizing radiation methods of MRI, hyperpolarized magnetic resonance and magnetic resonance spectroscopy, chemical exchange saturation transfer, and emerging optoacoustic (photoacoustic) imaging. We also briefly discuss the role of nuclear and optical imaging methods for research and clinical protocols.
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Affiliation(s)
- Vasilis Ntziachristos
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg 85764, Germany; Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Ismaningerstr. 22, Munich 81675, Germany.
| | - Miguel A Pleitez
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg 85764, Germany; Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Ismaningerstr. 22, Munich 81675, Germany
| | - Silvio Aime
- Molecular Imaging Center, Department of Molecular Biotechnologies and Health Sciences, University of Turin, Turin 10126, Italy
| | - Kevin M Brindle
- Department of Biochemistry, University of Cambridge, Old Addenbrooke's Site, Cambridge CB2 1GA, UK; Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
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22
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Farashishiko A, Slack JR, Botta M, Woods M. ParaCEST Agents Encapsulated in Reverse Nano-Assembled Capsules (RACs): How Slow Molecular Tumbling Can Quench CEST Contrast. Front Chem 2018; 6:96. [PMID: 29682499 PMCID: PMC5897432 DOI: 10.3389/fchem.2018.00096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/20/2018] [Indexed: 12/13/2022] Open
Abstract
Although paraCEST is a method with immense scope for generating image contrast in MRI, it suffers from the serious drawback of high detection limits. For a typical discrete paraCEST agent the detection limit is roughly an order of magnitude higher than that of a clinically used relaxation agent. One solution to this problem may be the incorporation of a large payload of paraCEST agents into a single macromolecular agent. Here we report a new synthetic method for accomplishing this goal: incorporating a large payload of the paraCEST agent DyDOTAM3+ into a Reverse Assembled nano-Capsule. An aggregate can be generated between this chelate and polyacrylic acid (PAA) after the addition of ethylene diamine. Subsequent addition of polyallylamine hydrochloride (PAH) followed by silica nanoparticles generated a robust encapsulating shell and afforded capsule with a mean hydrodynamic diameter of 650 ± 250 nm. Unfortunately this encapsulation did not have the effect of amplifying the CEST effect per agent, but quenched the CEST altogether. The quenching effect of encapsulation could be attributed to the effect of slowing molecular tumbling, which is inevitable when the chelate is incorporated into a nano-scale material. This increases the transverse relaxation rate of chelate protons and a theoretical examination using Solomon Bloembergen Morgan theory and the Bloch equations shows that the increase in the transverse relaxation rate constant for the amide protons, in even modestly sized nano-materials, is sufficient to significantly quench CEST.
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Affiliation(s)
- Annah Farashishiko
- Department of Chemistry, Portland State University, Portland, OR, United States
| | - Jacqueline R. Slack
- Department of Chemistry, Portland State University, Portland, OR, United States
| | - Mauro Botta
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale “Amedeo Avogadro”, Alessandria, Italy
| | - Mark Woods
- Department of Chemistry, Portland State University, Portland, OR, United States
- Advanced Imaging Research Center, Oregon Health and Science University, Portland, OR, United States
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