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Liu L, Chen YZ, Zhang SS, Chen XP, Lin GQ, Yin H, Feng CG, Zhang F. Multiplexed Analysis of Endogenous Guanidino Compounds via Isotope-Coded Doubly Charged Labeling: Application to Lung Cancer Tissues as a Case. Anal Chem 2021; 93:16862-16872. [PMID: 34894659 DOI: 10.1021/acs.analchem.1c03835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Endogenous guanidino compounds (GCs), nitrogen-containing metabolites, have very important physiological activities and participate in biochemical processes. Therefore, accurately characterizing the distribution of endogenous GCs and monitoring their concentration variations are of great significance. In this work, a new derivatization reagent, 4,4'-bis[3-(dimethylamino)propyl]benzyl (BDMAPB), with isotope-coded reagents was designed and synthesized for doubly charged labeling of GCs. BDMAPB-derivatized GCs not only promote the MS signal but also form multicharged quasimolecular ions and abundant fragment ions. With this reagent, an isotope-coded doubly charged labeling (ICDCL) strategy was developed for endogenous GCs with high-resolution liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF MS). The core of this methodology is a 4-fold multiplexed set of [d0]-/[d4]-/[d8]-/[d12]-BDMAPB that yields isotope-coded derivatized GCs. Following a methodological assessment, good linear responses in the range of 25 nM to 1 μM with correlation coefficients over 0.99 were achieved. The limit of detection and the limit of quantitation were below 5 and 25 nM, respectively. The intra- and interday precisions were less than 18%, and the accuracy was in the range of 77.3-122.0%. The percentage recovery in tissues was in the range of 85.1-113.7%. The results indicate that the developed method facilitates long-term testing and ensures accuracy and reliability. Finally, the method was applied for the simultaneous analysis of endogenous GCs in four types of lung tissues (solid adenocarcinoma, solid squamous-cell carcinoma, ground-glass carcinoma, and paracancerous tissues) for absolute quantification, nontargeted screening, and metabolic difference analysis. It is strongly believed that ICDCL combined with isotope-coded BDMAPB will benefit the analysis and study of endogenous GCs.
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Affiliation(s)
- Li Liu
- The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China
| | - Yan-Zhen Chen
- The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China
| | - Shu-Sheng Zhang
- The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China
| | - Xiu-Ping Chen
- The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China
| | - Guo-Qiang Lin
- The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China
| | - Hang Yin
- Department of Thoracic Surgery, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200127, P. R. China
| | - Chen-Guo Feng
- The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China
| | - Fang Zhang
- The Research Center of Chiral Drugs, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China
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Tůma P, Sommerová B, Koval D, Couderc F. Electrophoretic Determination of Symmetric and Asymmetric Dimethylarginine in Human Blood Plasma with Whole Capillary Sample Injection. Int J Mol Sci 2021; 22:2970. [PMID: 33804011 PMCID: PMC7998904 DOI: 10.3390/ijms22062970] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 12/16/2022] Open
Abstract
Asymmetric and symmetric dimethylarginines are toxic non-coded amino acids. They are formed by post-translational modifications and play multifunctional roles in some human diseases. Their determination in human blood plasma is performed using capillary electrophoresis with contactless conductivity detection. The separations are performed in a capillary covered with covalently bonded PAMAPTAC polymer, which generates anionic electroosmotic flow and the separation takes place in the counter-current regime. The background electrolyte is a 750 mM aqueous solution of acetic acid with pH 2.45. The plasma samples for analysis are treated by the addition of acetonitrile and injected into the capillary in a large volume, reaching 94.5% of the total volume of the capillary, and subsequently subjected to electrophoretic stacking. The attained LODs are 16 nm for ADMA and 22 nM for SDMA. The electrophoretic resolution of both isomers has a value of 5.3. The developed method is sufficiently sensitive for the determination of plasmatic levels of ADMA and SDMA. The determination does not require derivatization and the individual steps in the electrophoretic stacking are fully automated. The determined plasmatic levels for healthy individuals vary in the range 0.36-0.62 µM for ADMA and 0.32-0.70 µM for SDMA.
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Affiliation(s)
- Petr Tůma
- Department of Hygiene, Third Faculty of Medicine, Charles University, Ruská 87, 100 00 Prague 10, Czech Republic;
| | - Blanka Sommerová
- Department of Hygiene, Third Faculty of Medicine, Charles University, Ruská 87, 100 00 Prague 10, Czech Republic;
| | - Dušan Koval
- Institute of Organic Chemistry and Biochemistry, The Czech Academy of Sciences, Flemingovo n. 2, 166 10 Prague 6, Czech Republic;
| | - François Couderc
- Laboratoire des IMRCP UMR 5623, University Toulouse III-Paul Sabatier, 31062 Toulouse, France;
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Caruso G, Musso N, Grasso M, Costantino A, Lazzarino G, Tascedda F, Gulisano M, Lunte SM, Caraci F. Microfluidics as a Novel Tool for Biological and Toxicological Assays in Drug Discovery Processes: Focus on Microchip Electrophoresis. MICROMACHINES 2020; 11:E593. [PMID: 32549277 PMCID: PMC7344675 DOI: 10.3390/mi11060593] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 06/04/2020] [Accepted: 06/10/2020] [Indexed: 02/07/2023]
Abstract
The last decades of biological, toxicological, and pharmacological research have deeply changed the way researchers select the most appropriate 'pre-clinical model'. The absence of relevant animal models for many human diseases, as well as the inaccurate prognosis coming from 'conventional' pre-clinical models, are among the major reasons of the failures observed in clinical trials. This evidence has pushed several research groups to move more often from a classic cellular or animal modeling approach to an alternative and broader vision that includes the involvement of microfluidic-based technologies. The use of microfluidic devices offers several benefits including fast analysis times, high sensitivity and reproducibility, the ability to quantitate multiple chemical species, and the simulation of cellular response mimicking the closest human in vivo milieu. Therefore, they represent a useful way to study drug-organ interactions and related safety and toxicity, and to model organ development and various pathologies 'in a dish'. The present review will address the applicability of microfluidic-based technologies in different systems (2D and 3D). We will focus our attention on applications of microchip electrophoresis (ME) to biological and toxicological studies as well as in drug discovery and development processes. These include high-throughput single-cell gene expression profiling, simultaneous determination of antioxidants and reactive oxygen and nitrogen species, DNA analysis, and sensitive determination of neurotransmitters in biological fluids. We will discuss new data obtained by ME coupled to laser-induced fluorescence (ME-LIF) and electrochemical detection (ME-EC) regarding the production and degradation of nitric oxide, a fundamental signaling molecule regulating virtually every critical cellular function. Finally, the integration of microfluidics with recent innovative technologies-such as organoids, organ-on-chip, and 3D printing-for the design of new in vitro experimental devices will be presented with a specific attention to drug development applications. This 'composite' review highlights the potential impact of 2D and 3D microfluidic systems as a fast, inexpensive, and highly sensitive tool for high-throughput drug screening and preclinical toxicological studies.
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Affiliation(s)
- Giuseppe Caruso
- Oasi Research Institute—IRCCS, 94018 Troina (EN), Italy; (M.G.); (F.C.)
| | - Nicolò Musso
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, 95125 Catania, Italy; (N.M.); (G.L.)
| | - Margherita Grasso
- Oasi Research Institute—IRCCS, 94018 Troina (EN), Italy; (M.G.); (F.C.)
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; (A.C.); (M.G.)
| | - Angelita Costantino
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; (A.C.); (M.G.)
| | - Giuseppe Lazzarino
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, 95125 Catania, Italy; (N.M.); (G.L.)
| | - Fabio Tascedda
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy;
- Center for Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Massimo Gulisano
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; (A.C.); (M.G.)
- Molecular Preclinical and Translational Imaging Research Centre-IMPRonTE, University of Catania, 95125 Catania, Italy
- Interuniversity Consortium for Biotechnology, Area di Ricerca, Padriciano, 34149 Trieste, Italy
| | - Susan M. Lunte
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS 66047-1620, USA;
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS 66047-1620, USA
- Department of Chemistry, University of Kansas, Lawrence, KS 66047-1620, USA
| | - Filippo Caraci
- Oasi Research Institute—IRCCS, 94018 Troina (EN), Italy; (M.G.); (F.C.)
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; (A.C.); (M.G.)
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Fresta CG, Hogard ML, Caruso G, Melo Costa EE, Lazzarino G, Lunte SM. Monitoring carnosine uptake by RAW 264.7 macrophage cells using microchip electrophoresis with fluorescence detection. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2017; 9:402-408. [PMID: 29104617 PMCID: PMC5663230 DOI: 10.1039/c6ay03009b] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Carnosine, a dipeptide found in a variety of tissues, is believed to possess antioxidant properties. It serves as a scavenger of reactive nitrogen and oxygen species (RNOS), which are important stress mediators of pro-inflammatory conditions and can lead to macrophage activation. In this study, intracellular concentrations of carnosine in murine RAW 264.7 macrophage cells were determined using microchip electrophoresis with laser-induced fluorescence detection following derivatization with naphthalene-2,3-dicarboxaldehyde and cyanide. The method was linear from 25 nM to 5 μM with a limit of detection in cell lysate samples of 65 nM. Using the method of standard additions, the basal intracellular content of carnosine in macrophage cells was determined to be 0.079 ± 0.02 nmol/106 cells. The uptake of carnosine by these cells was then investigated under both physiological and pro-inflammatory conditions. There was a 2.8-fold increase in carnosine uptake for macrophages exposed to lipopolysaccharide and interferon-γ prior to incubation, compared to the controls. This suggests that macrophages may use carnosine uptake as a defense mechanism under pro-inflammatory conditions. Future studies will investigate the role of the carnosine transporter in carnosine uptake and its possible correlation with cell morphological changes observed after stimulation.
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Affiliation(s)
- Claudia G. Fresta
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, Kansas
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas
| | - Michael L. Hogard
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, Kansas
- Department of Chemistry, University of Kansas, Lawrence, Kansas
| | - Giuseppe Caruso
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, Kansas
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas
| | - Elton E. Melo Costa
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, Kansas
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Alagoas, Brazil
| | - Giuseppe Lazzarino
- Department of Biomedical and Biotechnological Sciences, Division of Medical Biochemistry, University of Catania, Italy
| | - Susan M. Lunte
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, Kansas
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas
- Department of Chemistry, University of Kansas, Lawrence, Kansas
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Faure M, Le Potier I, Pallandre A, Chebil S, Haghiri-Gosnet AM, Deslouis C, Maisonhaute E, Gamby J. Determination of the isomeric forms proportion of fluorogenic naphthalene-2,3-dicarboxaldehyde in a binary mixture of water:methanol using electrochemical methods. Talanta 2016; 148:494-501. [PMID: 26653477 DOI: 10.1016/j.talanta.2015.11.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Revised: 10/29/2015] [Accepted: 11/04/2015] [Indexed: 11/28/2022]
Abstract
The electrochemical response of the fluorogenic label naphthalene-2,3-dicarboxyaldehyde (NDA) in a binary mixture of water/methanol was characterized with cyclic voltammetry (CV) and differential pulse voltammetry (DPV) electrochemical techniques. Naphthalene-2,3-dicarboxyaldehyde does exist in three isomeric forms in aqueous solution: the unhydrated dialdehyde (DA), the acyclic monohydrated (MA) and the cyclic hemiacetal (HAC). The study underlines that the proportion of each of them varies according to the working pH. At low and high pH, the dialdehyde form is in larger proportion than the acyclic monohydrated form. Conversely at intermediate pH, the concentration of the acyclic form is in greater proportion than the dialdehyde form. These results allowed us to determine the optimal pH of 9 for which the labeling of biomolecules could be more efficient due to the base catalyzed regeneration of the unhydrated form. At this pH, the data processing from the analysis of measured currents and estimation of diffusion coefficients of each form according to the semi-empirical models of Wilke-Chang, Scheibel, Reddy-Doraiswamy and Lusis-Ratcliff allowed us to obtain the concentration of dialdehyde (0.28 mM), acyclic monohydrated (0.57 mM) and cyclic hemiacetal monohydrated (0.15 mM) forms starting from 1mM naphthalene-2,3-dicarboxyaldehyde.
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Affiliation(s)
- Mathilde Faure
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, 4 place Jussieu, F-75005 Paris, France
| | - Isabelle Le Potier
- CNRS, Institut Galien Paris-Sud, UMR 8612, F-92290 Châtenay-Malabry, France; Université Paris-Sud, Faculté de Pharmacie, 5 rue Jean-Baptiste Clément, 92290 Châtenay-Malabry, France
| | - Antoine Pallandre
- CNRS, Laboratoire de Photonique et de Nanostructures, UPR20, Marcoussis 91460, France; Université Paris-Sud, Faculté de Pharmacie, 5 rue Jean-Baptiste Clément, 92290 Châtenay-Malabry, France
| | - Syrine Chebil
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, 4 place Jussieu, F-75005 Paris, France
| | | | - Claude Deslouis
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, 4 place Jussieu, F-75005 Paris, France
| | - Emmanuel Maisonhaute
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, 4 place Jussieu, F-75005 Paris, France
| | - Jean Gamby
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire Interfaces et Systèmes Electrochimiques, 4 place Jussieu, F-75005 Paris, France.
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OBORNY NJ, COSTA EEM, SUNTORNSUK L, ABREU FC, LUNTE SM. Evaluation of a Portable Microchip Electrophoresis Fluorescence Detection System for the Analysis of Amino Acid Neurotransmitters in Brain Dialysis Samples. ANAL SCI 2016; 32:35-40. [PMID: 26753703 PMCID: PMC4875779 DOI: 10.2116/analsci.32.35] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 11/09/2015] [Indexed: 01/08/2023]
Abstract
A portable fluorescence detection system for use with microchip electrophoresis was developed and compared to a benchtop system. Using this system, six neuroactive amines commonly found in brain dialysate (arginine, citrulline, taurine, histamine, glutamate, and aspartate) were derivatized offline with naphthalene-2,3-dicarboxaldehyde/cyanide, separated electrophoretically, and detected by fluorescence. The limits of detection for the analytes of interest were 50 - 250 nM for the benchtop system and 250 nM - 1.3 μM for the portable system, both of which were adequate for most analyte detection in brain microdialysis samples. The portable system was then demonstrated for the detection of the same six amines in a rat brain microdialysis sample.
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Affiliation(s)
- Nathan J. OBORNY
- Department of Bioengineering, University of Kansas, Lawrence, KS, USA
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
| | - Elton E. Melo COSTA
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Alagoas, Brazil
| | - Leena SUNTORNSUK
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Fabiane C. ABREU
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Alagoas, Brazil
| | - Susan M. LUNTE
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS, USA
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
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Simultaneous Sensitive MEKC–LIF Determination of Homocysteine, Homoarginine, and Six Arginine Metabolic Derivatives in Fluids from Type 2 Diabetics with Peptic Ulcer Bleeding. Chromatographia 2015. [DOI: 10.1007/s10337-015-2919-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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8
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Wang X, Yi L, Guillo C, Roper MG. Micellar electrokinetic chromatography method for measuring amino acid secretions from islets of Langerhans. Electrophoresis 2015; 36:1172-8. [PMID: 25780900 DOI: 10.1002/elps.201400569] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/14/2015] [Accepted: 02/16/2015] [Indexed: 01/01/2023]
Abstract
Islets of Langerhans are responsible for maintaining glucose homeostasis through regulated secretion of hormones and other factors. It is hypothesized that amino acids secreted from islets play a critical role in cell functionality and viability. For example, glutamate and gamma-aminobutyric acid have been proposed to work as paracrine signaling molecules within islets to coordinate the release of hormone secretion; other amino acids, such as glutamine, leucine, alanine, and arginine, have been shown to stimulate or potentiate glucose-stimulated insulin secretion. To characterize the potential roles that these small molecules may play in islet physiology, derivatization of amino acids in high-salt buffers commonly used in islet experiments with naphthalene-2,3-dicarboxaldehyde and MEKC separation conditions were optimized. The optimized conditions used d-norvaline as the internal standard and allowed quantification of 14 amino acids with LODs ranging from 0.2 to 7 nM. The RSDs of the migration times were 0.04-0.54% and the RSDs of the peak areas were 0.2-5.8% for the various amino acids. The effects of glucose and 2,4-dinitrophenol on amino acid secretions from islets were tested and a suppressive effect of glucose on gamma-aminobutyric acid release was observed, likely acting through adenosine triphosphate inactivation of glutamate decarboxylase.
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Affiliation(s)
- Xue Wang
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Lian Yi
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Christelle Guillo
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Michael G Roper
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
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Linz TH, Lunte SM. Determination of Methylarginines in Infant Plasma by CE-LIF. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2014; 6:3990-3994. [PMID: 25621020 PMCID: PMC4303571 DOI: 10.1039/c4ay00340c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Methylarginines (MAs) are a class of nitric oxide synthase inhibitors that have been implicated in respiratory complications of critically ill infants. This paper describes the development of an analytical method to measure these compounds in the plasma of newborns using capillary electrophoresis (CE). The CE separation method was optimized to enable complete baseline resolution of the four MA analogues of interest. Sample preparation concerns for infant-derived samples were addressed by validating a heat-assisted extraction method for the analysis of low volume (≤100 µL) samples from a plasma matrix. It was determined that the sample matrix (plasma versus serum) did not affect the measured MA concentrations, while extracting smaller volumes of plasma that underwent heat-induced gelation afforded higher MA recoveries than larger volume samples. These methods were then applied to blood samples collected from infants housed in the neonatal intensive care unit. It was discovered that these newborns had significantly elevated concentrations of MAs at younger ages (< 6 months) while amounts were similar between infants 6 months old and adults. The data are preliminary, but demonstrate an interesting age dependence on the concentrations of these nitric oxide inhibitors, which has not been previously reported.
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Affiliation(s)
- Thomas H. Linz
- Department of Chemistry, University of Kansas, Lawrence, KS
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS
| | - Susan M. Lunte
- Department of Chemistry, University of Kansas, Lawrence, KS
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, KS
- Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS
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Poinsot V, Ong-Meang V, Gavard P, Couderc F. Recent advances in amino acid analysis by capillary electromigration methods, 2011-2013. Electrophoresis 2013; 35:50-68. [DOI: 10.1002/elps.201300306] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 09/11/2013] [Accepted: 09/11/2013] [Indexed: 12/28/2022]
Affiliation(s)
- Véréna Poinsot
- Laboratoire des IMRCP; Université Paul Sabatier; Toulouse France
| | | | - Pierre Gavard
- Laboratoire des IMRCP; Université Paul Sabatier; Toulouse France
| | - François Couderc
- Laboratoire des IMRCP; Université Paul Sabatier; Toulouse France
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11
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Linz TH, Lunte SM. Heat-assisted extraction for the determination of methylarginines in serum by CE. Electrophoresis 2013; 34:1693-700. [PMID: 23417924 DOI: 10.1002/elps.201200567] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 11/15/2012] [Accepted: 11/19/2012] [Indexed: 01/05/2023]
Abstract
Methylarginines (MAs) are potent vasoconstrictors that have been reported to be present at elevated concentrations in the blood of patients suffering from cardiovascular disease. To determine the diagnostic potential of MAs for cardiovascular disease, a method capable of rapidly quantifying their endogenous concentrations from serum samples is required. To that end, a heat-assisted extraction method was developed. Serum was first rapidly heated, causing it to congeal into a gel, and then subjected to solid-liquid extraction. The extraction solution was then derivatized with a fluorogenic dye and analyzed by CE-LIF to permit quantitation of the MAs. This heat-assisted extraction procedure allowed a no-net-dilution extraction of the analytes to be performed into a solvent compatible with the subsequent CE analysis. This enabled direct detection of low-abundance analytes, such as MAs, without the need for a preconcentration step. This sample preparation method was compared with a commonly used solid-phase extraction method for MA analysis. Endogenous MA concentrations determined by both the heating and solid-phase extraction methods were found to be in good agreement with each other and with values previously reported in the literature.
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Affiliation(s)
- Thomas H Linz
- Department of Chemistry, University of Kansas, Lawrence, KS, USA
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