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Huang L, Yan X. Construction of a genetic linkage map in Pyropia yezoensis (Bangiales, Rhodophyta) and QTL analysis of several economic traits of blades. PLoS One 2019; 14:e0209128. [PMID: 30849086 PMCID: PMC6407771 DOI: 10.1371/journal.pone.0209128] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 02/20/2019] [Indexed: 11/18/2022] Open
Abstract
Pyropia yezoensis is an economically important seaweed but its molecular genetics is poorly understood. In the present study, we used a doubled haploid (DH) population that was established in our previous work to construct a genetic linkage map of P. yezoensis and analyze the quantitative trait loci (QTLs) of blades. The DH population was genotyped with fluorescent sequence-related amplified polymorphism (SRAP) markers. A chi-square test identified 301 loci with normal segregation (P ≥ 0.01) and 96 loci (24.18%) with low-level skewed segregation (0.001 ≤ P < 0.01). The genetic map was constructed after a total of 92 loci were assembled into three linkage groups (LGs). The map spanned 557.36 cM covering 93.71% of the estimated genome, with a mean interlocus space of 6.23 cM. Kolmogorov-Smirnov test (α = 5%) showed a uniform distribution of the markers along each LG. On the genetic map, 10 QTLs associated with five economic traits of blades were detected. One QTL was for length, one for width, two for fresh weight, two for specific growth rate of length and four for specific growth rate of fresh weight. These QTLs could explain 2.29–7.87% of the trait variations, indicating that their effects were all minor. The results may serve as a framework for future marker-assisted breeding in P. yezoensis.
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Affiliation(s)
- Linbin Huang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, Shanghai, P. R. China
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai, P. R. China
- International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai, P. R. China
| | - Xinghong Yan
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, Shanghai, P. R. China
- National Demonstration Center for Experimental Fisheries Science Education (Shanghai Ocean University), Shanghai, P. R. China
- International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai, P. R. China
- * E-mail:
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2
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Posch TN, Pütz M, Martin N, Huhn C. Electromigrative separation techniques in forensic science: combining selectivity, sensitivity, and robustness. Anal Bioanal Chem 2014; 407:23-58. [PMID: 25381613 DOI: 10.1007/s00216-014-8271-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 10/12/2014] [Accepted: 10/14/2014] [Indexed: 01/27/2023]
Abstract
In this review we introduce the advantages and limitations of electromigrative separation techniques in forensic toxicology. We thus present a summary of illustrative studies and our own experience in the field together with established methods from the German Federal Criminal Police Office rather than a complete survey. We focus on the analytical aspects of analytes' physicochemical characteristics (e.g. polarity, stereoisomers) and analytical challenges including matrix tolerance, separation from compounds present in large excess, sample volumes, and orthogonality. For these aspects we want to reveal the specific advantages over more traditional methods. Both detailed studies and profiling and screening studies are taken into account. Care was taken to nearly exclusively document well-validated methods outstanding for the analytical challenge discussed. Special attention was paid to aspects exclusive to electromigrative separation techniques, including the use of the mobility axis, the potential for on-site instrumentation, and the capillary format for immunoassays. The review concludes with an introductory guide to method development for different separation modes, presenting typical buffer systems as starting points for different analyte classes. The objective of this review is to provide an orientation for users in separation science considering using capillary electrophoresis in their laboratory in the future.
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Affiliation(s)
- Tjorben Nils Posch
- Forschungszentrum Jülich GmbH, Central Institute for Engineering, Electronics and Analytics, Analytics ZEA-3, 52425, Jülich, Germany
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3
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Nguyen TV, Murray V. The electrophoretic mobility of DNA fragments differing by a single 3'-terminal nucleotide in an automated capillary DNA sequencer. Biomed Chromatogr 2012; 27:390-5. [PMID: 22911138 DOI: 10.1002/bmc.2804] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/16/2012] [Accepted: 07/25/2012] [Indexed: 12/15/2022]
Abstract
The electrophoretic mobility of DNA fragments that differ by a single 3'-terminal nucleotide was assessed by capillary electrophoresis. This was accomplished using dideoxy sequencing with a 5'-fluorescently labelled primer to generate DNA fragments with 3'-hydrogen ends. The resulting DNA fragments were electrophoresed on the ABI 3730 automated capillary sequencer, and the data were analysed with the GeneMapper software to determine the electrophoretic mobility differences on addition of a 3'-terminal nucleotide. It was found that the 3'-terminal nucleotide gave rise to different electrophoretic mobility profiles depending on the identity of the terminal nucleotide. The apparent electrophoretic mobility was (faster) -C > -A > -T > -G (slower). The C-terminated fragments were the fastest and the G-terminated fragments the slowest, relative to other nucleotides. It was proposed that the terminal nucleotide effect was due to changes in partial net charges on the nucleotides that resulted in alterations in the electrophoretic mobility of the DNA fragments in the automated capillary DNA sequencer. Other alternative explanations are also discussed.
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Affiliation(s)
- Trung V Nguyen
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
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4
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Wang L, Ota N, Romanova EV, Sweedler JV. A novel pyridoxal 5'-phosphate-dependent amino acid racemase in the Aplysia californica central nervous system. J Biol Chem 2011; 286:13765-74. [PMID: 21343289 DOI: 10.1074/jbc.m110.178228] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
D-aspartate (D-Asp) is found in specific neurons, transported to neuronal terminals and released in a stimulation-dependent manner. Because D-Asp formation is not well understood, determining its function has proved challenging. Significant levels of D-Asp are present in the cerebral ganglion of the F- and C-clusters of the invertebrate Aplysia californica, and D-Asp appears to be involved in cell-cell communication in this system. Here, we describe a novel protein, DAR1, from A. californica that can convert aspartate and serine to their other chiral form in a pyridoxal 5'-phosphate (PLP)-dependent manner. DAR1 has a predicted length of 325 amino acids and is 55% identical to the bivalve aspartate racemase, EC 5.1.1.13, and 41% identical to the mammalian serine racemase, EC 5.1.1.18. However, it is only 14% identical to the recently reported mammalian aspartate racemase, DR, which is closely related to glutamate-oxaloacetate transaminase, EC 2.6.1.1. Using whole-mount immunohistochemistry staining of the A. californica central nervous system, we localized DAR1-like immunoreactivity to the medial region of the cerebral ganglion where the F- and C-clusters are situated. The biochemical and functional similarities between DAR1 and other animal serine and aspartate racemases make it valuable for examining PLP-dependent racemases, promising to increase our knowledge of enzyme regulation and ultimately, D-serine and D-Asp signaling pathways.
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Affiliation(s)
- Liping Wang
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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5
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Bioanalytical applications of capillary electrophoresis with laser-induced native fluorescence detection. Bioanalysis 2010; 2:1641-53. [DOI: 10.4155/bio.10.72] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
In this article we describe recent developments and applications of capillary electrophoresis (CE) coupled with laser-induced native fluorescence (LINF) detection in the analysis of biological, pharmaceutical and environmental samples. Compared with traditional UV absorbance detection used in CE, the LINF technique can greatly improve the concentration sensitivity of CE without the need for derivatization; the only requirement being that the analyte must have native fluorescence. Instrumentation and laser sources used in CE–LINF are summarized and specific applications of CE–LINF to small-biomolecule analysis, profiling of human biofluids, detection of native fluorescent peptides and proteins, single-cell analysis and the use of online sample preconcentration methods are also reviewed in detail.
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6
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Microwave-accelerated derivatization for capillary electrophoresis with laser-induced fluorescence detection: A case study for determination of histidine, 1- and 3-methylhistidine in human urine. Talanta 2010; 82:72-7. [DOI: 10.1016/j.talanta.2010.03.061] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 03/25/2010] [Accepted: 03/27/2010] [Indexed: 11/19/2022]
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7
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Li H, Yan ZY. Analysis of amino acid neurotransmitters in hypothalamus of rats during cerebral ischemia-reperfusion by microdialysis and capillary electrophoresis. Biomed Chromatogr 2010; 24:1185-92. [DOI: 10.1002/bmc.1425] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Ryvolová M, Preisler J, Foret F, Hauser PC, Krásenský P, Paull B, Macka M. Combined Contactless Conductometric, Photometric, and Fluorimetric Single Point Detector for Capillary Separation Methods. Anal Chem 2009; 82:129-35. [DOI: 10.1021/ac902376v] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Markéta Ryvolová
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Jan Preisler
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - František Foret
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Peter C. Hauser
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Pavel Krásenský
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Brett Paull
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Mirek Macka
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
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Feás X, Fente CA, Hosseini SV, Cepeda A. New near ultraviolet laser-induced native fluorescence detection coupled to HPLC to analyse residues of oxolinic acid and flumequine: a comparison with conventional xenon flash lamp Nuevo método de análisis de residuos de oxolínico y flumequina utilizando la detección de la fluorescencia nativa inducida por láser acoplada en el ultravioleta cercano acoplada al HPLC: comparación con la lámpara de xenon convencional. CYTA - JOURNAL OF FOOD 2009. [DOI: 10.1080/11358120902850552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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10
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Lai HH, Quinto-Su PA, Sims CE, Bachman M, Li GP, Venugopalan V, Allbritton NL. Characterization and use of laser-based lysis for cell analysis on-chip. J R Soc Interface 2008; 5 Suppl 2:S113-21. [PMID: 18583277 DOI: 10.1098/rsif.2008.0177.focus] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We demonstrate the use of a pulsed laser microbeam for cell lysis followed by electrophoretic separation of cellular analytes in a microfluidic device. The influence of pulse energy and laser focal point within the microchannel on the threshold for plasma formation was measured. The thickness of the poly(dimethylsiloxane) (PDMS) layer through which the beam travelled was a critical determinant of the threshold energy. An effective optical path length, Leff, for the laser beam can be used to predict the threshold for optical breakdown at different microchannel locations. A key benefit of laser-based cell lysis is the very limited zone (less than 5 microm) of lysis. A second asset is the rapid cell lysis times (approx. microseconds). These features enable two analytes, fluorescein and Oregon Green, from a cell to be electrophoretically separated in the channel in which cell lysis occurred. The resolution and efficiency of the separation of the cellular analytes are similar to those of standards demonstrating the feasibility of using a pulsed laser microbeam in single-cell analysis.
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Affiliation(s)
- Hsuan-Hong Lai
- Department of Electrical Engineering and Computer Science, University of California, Irvine, CA 92697, USA
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11
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Zhao S, Wang J, Ye F, Liu YM. Determination of uric acid in human urine and serum by capillary electrophoresis with chemiluminescence detection. Anal Biochem 2008; 378:127-31. [DOI: 10.1016/j.ab.2008.04.014] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2007] [Revised: 04/04/2008] [Accepted: 04/07/2008] [Indexed: 11/28/2022]
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12
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Miguéns M, Del Olmo N, Higuera-Matas A, Torres I, García-Lecumberri C, Ambrosio E. Glutamate and aspartate levels in the nucleus accumbens during cocaine self-administration and extinction: a time course microdialysis study. Psychopharmacology (Berl) 2008; 196:303-13. [PMID: 17940751 DOI: 10.1007/s00213-007-0958-x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Accepted: 09/19/2007] [Indexed: 11/29/2022]
Abstract
RATIONALE Accumbal excitatory amino acid (EAA) transmission has been implicated in cocaine addiction. However, the time course effects of extinction of cocaine self-administration on EAAs are unknown. OBJECTIVES The objective of this study was to define the time course of cocaine self-administration and extinction effects on glutamate and aspartate levels in the nucleus accumbens. MATERIALS AND METHODS Rats were trained to self-administer cocaine for 20 days, and the levels of extracellular glutamate and aspartate were measured by in vivo microdialysis both during cocaine self-administration and after a priming cocaine injection at different time points after extinction (1, 5, or 10 days). A food-reinforced control group was also included in this study. Furthermore, the effect of acute i.v. cocaine administration (0, 1, 2, or 4 mg/kg) on glutamate and aspartate levels was also evaluated. RESULTS At any of the dose tested, acute i.v. cocaine did not affect the levels of glutamate or aspartate in the Nacc. In contrast, glutamate levels were reduced in animals trained to self-administer cocaine, although they augmented substantially during a subsequent session of cocaine self-administration, and similar changes were not observed in food-reinforced controls. After 1 or 5, but not after 10 days of extinction, the glutamate levels were also reduced, and the ability of i.v. cocaine priming injections to increase glutamate levels followed a similar time course. These effects were specific, as aspartate levels were not affected by any administration protocol. CONCLUSIONS These data suggest that glutamatergic transmission could be involved in the maintenance of cocaine self-administration and in the early phases of abstinence.
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Affiliation(s)
- M Miguéns
- Departamento de Psicobiología, Facultad de Psicología, UNED, C/ Juan del Rosal no. 10, 28040 Madrid, Spain
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13
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Liu Q, Liu Y, Li Y, Yao S. Nonaqueous capillary electrophoresis coupled with laser-induced native fluorescence detection for the analysis of berberine, palmatine, and jatrorrhizine in Chinese herbal medicines. J Sep Sci 2007; 29:1268-74. [PMID: 16833085 DOI: 10.1002/jssc.200600032] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
LIF detection is one of the most sensitive detection methods for CE. However, its application is limited because the analyte is usually required to be derivatized with a fluorescent label. As a result, LIF is seldom used to analyze active ingredients in plants. In this work, we introduce a rapid, simple, and sensitive method of nonaqueous CE (NACE) coupled with laser-induced native fluorescence detection for the simultaneous analysis of berberine, palmatine, and jatrorrhizine. This method skillfully utilizes the native fluorescence of these alkaloids and requires no troublesome fluorescent derivatization. As these alkaloids can fluoresce to some degree, they were simply detected by a commercially available 488 nm Ar+ laser. The native fluorescence of the analytes was greatly enhanced by nonaqueous media. Compared with the reported UV detection method, much lower LOD was achieved (6.0 ng/mL for berberine, 7.5 ng/mL for palmatine, and 380 ng/mL for jatrorrhizine). This method was successfully applied to analyze berberine, palmatine, and jatrorrhizine in two Chinese herbal medicines, Rhizoma coptidis and Caulis mahoniae.
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Affiliation(s)
- Qian Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, P. R. China
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14
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Williams BJ, Cameron CJ, Workman R, Broeckling CD, Sumner LW, Smith JT. Amino acid profiling in plant cell cultures: an inter-laboratory comparison of CE-MS and GC-MS. Electrophoresis 2007; 28:1371-9. [PMID: 17377946 DOI: 10.1002/elps.200600609] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A CE-MS method for metabolic profiling of amino acids was developed and used in an integrated functional genomics project to study the response of Medicago truncatula liquid suspension cell cultures to stress. This project required the analysis of more than 500 root cell culture extracts. The CE-MS method profiled 20 biologically important amino acids. The CE-MS method required no sample derivatization prior to injection and used minimal sample preparation. The method is described in terms of CE and MS operational parameters, reproducibility of migration times and response ratios, sample preparation, sample throughput, and reliability. This method was then compared with a previously published report that used GC-MS metabolic profiling for the same tissues. The data reveal a high level of similarity between the CE-MS and GC-MS amino acid profiling methods, thus supporting these as complementary technologies for metabolomics. We conclude that CE-MS is a valid alternative to GC-MS for targeted profiling of metabolites, such as amino acids, and possesses some significant advantages over GC-MS.
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Affiliation(s)
- Brad J Williams
- Southeastern Oklahoma State University, Physical Sciences, Durant, OK 74701-0609, USA
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15
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Cellar NA, Burns ST, Meiners JC, Chen H, Kennedy RT. Microfluidic chip for low-flow push-pull perfusion sampling in vivo with on-line analysis of amino acids. Anal Chem 2007; 77:7067-73. [PMID: 16255611 DOI: 10.1021/ac0510033] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Multilayer soft lithography was used to prepare a poly(dimethylsiloxane) microfluidic chip that allows for in vivo sampling of amino acid neurotransmitters by low-flow push-pull perfusion. The chip incorporates a pneumatically actuated peristaltic pump to deliver artificial cerebrospinal fluid to a push-pull perfusion probe, pull sample from the probe, perform on-line derivatization with o-phthaldialdehyde, and push derivatized amino acids into the flow-gated injector of a high-speed capillary electrophoresis-laser-induced fluorescence instrument. Peristalsis was achieved by sequential actuation of six, 200 microm wide by 15 microm high control valves that drove fluid through three fluidic channels of equal dimensions. Electropherograms with 100,000 theoretical plates were acquired at approximately 20-s intervals. Relative standard deviations of peak heights were 4% in vitro, and detection limits for the excitatory amino acids were approximately 60 nM. For in vivo measurements, push-pull probes were implanted in the striatum of anesthetized rats and amino acid concentrations were monitored while sampling at 50 nL/min. o-Phosphorylethanolamine, glutamate, aspartate, taurine, glutamine, serine, and glycine were all detected with stable peak heights observed for over 4 h with relative standard deviations of 10% in vivo. Basal concentrations of glutamate were 1.9 +/- 0.6 microM (n = 4) in good agreement with similar methods. Monitoring of dynamic changes of neurotransmitters resulting from 10-min applications of 70 mM K(+) through the push channel of the pump was demonstrated. The combined system allows temporal resolution for multianalyte monitoring of approximately 45 s with spatial resolution 65-fold better than conventional microdialysis probe with 4-mm length. The system demonstrates the feasibility of sampling from a complex microenvironment with transfer to a microfluidic device for on-line analysis.
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Affiliation(s)
- Nicholas A Cellar
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
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16
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Kirschner DL, Jaramillo M, Green TK. Enantioseparation and stacking of Cyanobenz[f]isoindole-amino acids by reverse polarity capillary electrophoresis and sulfated beta-cyclodextrin. Anal Chem 2007; 79:736-43. [PMID: 17222044 DOI: 10.1021/ac061725+] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A capillary electrophoresis method with laser-induced fluorescence detection for the chiral separation of cyanobenz[f]isoindole (CBI) derivatives of amino acids was developed and optimized. The enantioseparations are accomplished with sulfated beta-CD (S-beta-CD) as chiral selector at low pH and reverse polarity. BGE conditions were optimized for CBI-serine and then applied to other CBI-amino acids. Baseline resolution of 13 CBI-amino acids was achieved using a single BGE formulation of 2 wt % S-beta-CD in 25 mM phosphate buffer at pH 2.00 and a voltage of -30 kV. pH is the most critical BGE parameter affecting resolution. At 2 wt % S-beta-CD, CBI-serine enantiomers are baseline-resolved at pH 2.00 but no resolution is obtained at pH 3.00. l-Glutamate, l-aspartate and d-serine are simultaneously quantified in the microdialysate of an arctic ground squirrel to illustrate the application to biological samples. Dilute solutions of the CBI-amino acids in water can be stacked by hydrodynamic injection with a 100-fold improvement in signal-to-noise ratio without loss of chiral resolution. The stacking is proposed to consist of field-amplified migration, pH-mediated stacking, and sweeping by S-beta-CD. The limit of detections for CBI-dl-serine and CBI-dl-glutamate are determined as 0.20 and 0.30 nM, respectively. The stacking method was not applicable to the high ionic strength microdialysates.
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Affiliation(s)
- Daniel L Kirschner
- Department of Chemistry & Biochemistry, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska 99775, USA
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Kustos I, Kocsis B, Kilár F. Bacterial outer membrane protein analysis by electrophoresis and microchip technology. Expert Rev Proteomics 2007; 4:91-106. [PMID: 17288518 DOI: 10.1586/14789450.4.1.91] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Outer membrane proteins are indispensable components of bacterial cells and participate in several relevant functions of the microorganisms. Changes in the outer membrane protein composition might alter antibiotic sensitivity and pathogenicity. Furthermore, the effects of various factors on outer membrane protein expression, such as antibiotic treatment, mutation, changes in the environment, lipopolysaccharide modification and biofilm formation, have been analyzed. Traditionally, the outer membrane protein profile determination was performed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Converting this technique to capillary electrophoresis format resulted in faster separation, lower sample consumption and automation. Coupling capillary electrophoresis with mass spectrometry enabled the fast identification of bacterial proteins, while immediate quantitative analysis permitted the determination of up- and downregulation of certain outer membrane proteins. Adapting capillary electrophoresis to microchip format ensured a further ten- to 100-fold decrease in separation time. Application of different separation techniques combined with various sensitive detector systems has ensured further opportunities in the field of high-throughput bacterial protein analysis. This review provides an overview using selected examples of outer membrane proteins and the development and application of the electrophoretic and microchip technologies for the analysis of these proteins.
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Affiliation(s)
- Ildikó Kustos
- University of Pécs, Department of Medical Microbiology & Immunology, Faculty of Medicine, Pécs, Hungary.
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18
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Phillips TM, Smith PD. IMMUNOAFFINITY ANALYSIS OF SUBSTANCE P IN COMPLEX BIOLOGICAL FLUIDS: ANALYSIS OF SUB-MICROLITER SAMPLES. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120015881] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Sano M, Nishino I. Assay for spermidine synthase activity by micellar electrokinetic chromatography with laser-induced fluorescence detection. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 845:80-3. [PMID: 16931179 DOI: 10.1016/j.jchromb.2006.07.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Revised: 06/23/2006] [Accepted: 07/24/2006] [Indexed: 11/29/2022]
Abstract
An assay for spermidine synthase (SPDS) activity in rat liver has been developed using micellar electrokinetic chromatography (MEKC) with laser-induced fluorescence (LIF) detection to enable the discovery of SPDS inhibitors. The assay was established by estimating the amount of spermidine (SPD) produced from the putrescine (PUT) present by SPDS. The SPD in an enzyme reaction mixture of homogenized rat liver could directly react with 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-F) as a fluorescence derivatization reagent. The NBD derivatives of SPD and PUT could be separated and detected by MEKC-LIF detection within 15 min. The IC(50) value measured for SPDS inhibitor, 4-methylcyclohexylamine, in rat liver by this assay was consistent with published data. Our SPDS assay using MEKC-LIF is simple and allows easy determination of SPDS activity in homogenized samples without troublesome procedures such as preparation of antibody or fluorescence-labeled substrate. The assay should be effective for discovering the SPDS inhibitors using biological samples.
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Affiliation(s)
- Masatake Sano
- Shionogi Research Laboratories, Shionogi & Co. Ltd., 12-4, Sagisu-5-Chome, Osaka 553-0002, Japan.
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Abstract
This paper provides an overview on the current status of the analysis of biogenic amines by CE. The basic CE separation and detection strategies for the analysis of biogenic amines are briefly described. CZE and MEKC that provide highly efficient and reproducible analysis of biogenic amines are particularly surveyed. With respect to the detection of biogenic amines, we focus on LIF, UV-visible absorption, electrochemiluminescence, and MS. Derivatization strategies, indirect methods, and on-line concentration techniques such as field-amplified sample stacking, sweeping, and use of polymer solution are described. To show the practicality of CE, we highlight currently developed techniques for the determinations of biogenic amines in biological samples, including foods, beverages, cerebrospinal fluids, urine, and single cells.
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Affiliation(s)
- Tai-Chia Chiu
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
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21
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Fang L, Kang J, Yin XB, Yang X, Wang E. CE coupling with end-column electrochemiluminescence detection for chiral separation of disopyramide. Electrophoresis 2006; 27:4516-22. [PMID: 17066381 DOI: 10.1002/elps.200600114] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
CE with electrochemiluminescence (ECL) detection technique was successfully applied for the chiral separation of a kind of class IA antiarrhythmic racemic drug. To the best of our knowledge, this is the first report of ECL detection used in chiral CE. To get better detection sensitivity and good enantioresolution at the same time, the conditions of capillary inlet and outlet buffer were systematically optimized. Unlike the traditional chiral separation method, the buffers we used in the capillary inlet and outlet differed from each other in terms of buffer pH, ionic strength, type of BGE as well as buffer composition. Under the optimum conditions, baseline enantioseparation and highly sensitive detection of the enantiomers were achieved. Wide linear relationship of each enantiomer was achieved in the range of 5 x 10(-7) to 2 x 10(-5) mol/L with relative coefficients of 0.996 and 0.997, respectively. The detection limits were estimated to be 8 x 10(-8) and 1.0 x 10(-7) mol/L (S/N = 3) for the enantiomers, respectively. In addition, a successful application of this new method to the chiral separation of the racemic drug in spiked plasma samples confirmed the validity and applicability of the chiral CE-ECL method.
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Affiliation(s)
- Lanyun Fang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Science, Graduate School of the Chinese Academy of Sciences, Changchun, China
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22
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Lin YW, Chang HT. Analysis of double-stranded DNA by capillary electrophoresis using poly(ethylene oxide) in the presence of hexadecyltrimethylammonium bromide. J Chromatogr A 2006; 1130:206-11. [PMID: 16597443 DOI: 10.1016/j.chroma.2006.03.050] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2006] [Revised: 03/01/2006] [Accepted: 03/17/2006] [Indexed: 01/23/2023]
Abstract
The impact of hexadecyltrimethylammonium bromide (CTAB) on the separation of ds-DNA by capillary electrophoresis in conjunction with laser-induced fluorescence (CE-LIF) detection using poly(ethylene oxide) (PEO) solution is described. The use of CTAB for improved separation reproducibility and efficiency of DNA has not been demonstrated although it is widely used for controlling the magnitude and direction of electroosmotic flow in CE. With increasing CTAB concentration, the interactions of DNA with ethidium bromide (EtBr) and with the capillary wall decrease. For the separation of DNA fragments with the sizes ranging from several base pairs (bp) to 2,176 bp, a polymer solution consisting of 0.75% poly(ethylene oxide), 100 mM TB buffer (pH 8.0), 25 microg/mL EtBr, and 0.36 microg/mL CTAB is proper. Using the PEO solution, we separated a mixture of DNA markers V (pBR 322/HaeIII digest) and VI (pBR 328/BglI digest and pBR 328/HinfI digest) within 8 min at -375 V/cm, with the limit of detection of 2.0 ng/mL based on the peak height for the 18-bp DNA fragment. The method is highly efficient (>10(6)plate/m), repeatable (RSD of the migration times <1.5%), and sensitive. In addition, it is convenient to fill a capillary (75 microm in diameter) with such a low-viscosity PEO solution by syringe pushing.
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Affiliation(s)
- Yang-Wei Lin
- Department of Chemistry, National Taiwan University, Section 4, Roosevelt Road, Taipei, Taiwan, ROC
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23
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Venton BJ, Robinson TE, Kennedy RT, Maren S. Dynamic amino acid increases in the basolateral amygdala during acquisition and expression of conditioned fear. Eur J Neurosci 2006; 23:3391-8. [PMID: 16820029 DOI: 10.1111/j.1460-9568.2006.04841.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Glutamate and gamma-aminobutyric acid (GABA) release in the amygdala are thought to be crucial for the acquisition and expression of fear memories, but the time course of amino acid changes during conditioning is unknown. We used rapid-sampling microdialysis with 14 s temporal resolution to address this issue. During auditory fear conditioning, large, rapid and transient increases in glutamate and GABA were detected, but only during the first noise-shock pairing. In contrast, rats receiving unsignaled shocks during contextual fear conditioning showed no changes in GABA and less glutamate release for the initial shock, but increased glutamate release during later shocks. Expression of conditioned fear to either a white noise or the context previously paired with shock produced similar rapid and transient increases in many amino acids in the amygdala. These experiments demonstrate glutamate and GABA levels in the amygdala are differentially modulated during auditory and contextual fear learning, and are transiently increased during the expression of fear memories.
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Affiliation(s)
- B Jill Venton
- Department of Chemistry, University of Michigan, 930 N. University, Ann Arbor, MI 48109-1055, USA.
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24
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Pittet P, Lu GN, Bertoncini N, Renaud L. CMOS absorbance detection system for capillary electrophoresis. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2006. [DOI: 10.1016/j.msec.2005.10.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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25
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Chapter 3.1 Liquid chromatographic methods used for microdialysis: an overview. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/s1569-7339(06)16013-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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26
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Hsieh MM, Chang HT. Impact of halides on the simultaneous separation of aromatic amines and their acidic metabolites by capillary electrophoresis with laser-induced native fluorescence detection under acidic conditions. J Chromatogr A 2006; 1102:302-8. [PMID: 16325830 DOI: 10.1016/j.chroma.2005.11.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2005] [Revised: 10/28/2005] [Accepted: 11/01/2005] [Indexed: 11/15/2022]
Abstract
This paper describes a simple, sensitive, efficient, and rapid method for simultaneous analysis of biologically active amines and acids by capillary electrophoresis in conjunction with laser-induced native fluorescence detection (CE-LINF) using a diode pumped solid state nanolaser at 266 nm. In order to optimize resolution of the amines that were prepared in 10.0 mM formate-Tris (FT) solutions, 10.0 mM FT solutions with and without containing halides were used to fill the capillary and reservoirs, respectively. The electrophoretic mobilities of tryptamine (TA) and serotonin (5-HT) at pH 4.0 decrease with the increase in halide concentration (0-10.0 mM). Taken together with a great effect of iodide than other halides, we suggest that the formation of ion pairs is a main contributor for altering the migration of the amines. In order to simultaneously analyze the amines and their metabolites (acids) at low pH, a high bulk EOF is required. The analysis of 10 anlytes including amines and acids was completed within 12 min by CE-LINF using a capillary treated with 0.5M NaOH and then filled with 10.0 mM FT solutions (pH 4.0) containing 10.0 mM KCl prior to analysis. The limits of detection for TA and 5-hydroxyindole-3-acetic acid (5-HIAA) are 0.12 and 6.0 nM, respectively. The present method has been further validated by analyzing urine samples, with an RSD less than 3.1% (migration times) and 3.9% (concentration).
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Affiliation(s)
- Ming-Mu Hsieh
- Department of Applied Chemistry, Fooyin University, 151 Chin-Hsueh Road, Ta-Liao Hsiang, 831 Kaohsiung Hsien, Taiwan.
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27
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Babu C V S, Song EJ, Babar SME, Wi MH, Yoo YS. Capillary electrophoresis at the omics level: Towards systems biology. Electrophoresis 2006; 27:97-110. [PMID: 16421959 DOI: 10.1002/elps.200500511] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Emerging systems biology aims at integrating the enormous amount of existing omics data in order to better understand their functional relationships at a whole systems level. These huge datasets can be obtained through advances in high-throughput, sensitive, precise, and accurate analytical instrumentation and technological innovation. Separation sciences play an important role in revealing biological processes at various omic levels. From the perspective of systems biology, CE is a strong candidate for high-throughput, sensitive data generation which is capable of tackling the challenges in acquiring qualitative and quantitative knowledge through a system-level study. This review focuses on the applicability of CE to systems-based analytical data at the genomic, transcriptomic, proteomic, and metabolomic levels.
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Affiliation(s)
- Suresh Babu C V
- Bioanalysis and Biotransformation Research Center, Korea Institute of Science and Technology, Cheongryang, Seoul, Korea
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28
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Venton BJ, Robinson TE, Kennedy RT. Transient changes in nucleus accumbens amino acid concentrations correlate with individual responsivity to the predator fox odor 2,5-dihydro-2,4,5-trimethylthiazoline. J Neurochem 2005; 96:236-46. [PMID: 16300631 DOI: 10.1111/j.1471-4159.2005.03549.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Predator odors elicit fear and defensive behavioral responses in rats, but a wide range of individual responsivity exists. The aim of this study was to examine whether individual differences in behavioral responsivity correlate with differences in amino acid neurotransmission to a predator fox odor, 2,5-dihydro-2,4,5-trimethylthiazoline (TMT). We investigated the time course of behaviorally evoked amino acid neurotransmitter changes in the nucleus accumbens using on-line microdialysis coupled to capillary electrophoresis with 14-s temporal resolution. One subset of animals (high responders) showed a large, biphasic increase in amino acids, such as glutamate and GABA, which lasted about 3 min. These neurochemical changes were highly correlated with increases in locomotion and burrowing, but lagged behind the behavioral changes by 2 min. A second subset of rats (low responders) showed neither behavioral activation nor changes in amino acid neurotransmission. As a positive control, rats were subjected to tail pinch, which evoked transient changes in amino acids in all animals. Cocaine (2 mg/kg, i.v.) increased locomotion but not amino acid levels. This work demonstrates that rapid and transient increases in amino acid neurotransmitters correlate with behavioral reactivity to salient stimuli.
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Affiliation(s)
- B Jill Venton
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, USA
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29
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Eberhard J, Eisenbeiss AK, Braun A, Hedderich J, Jepsen S. Evaluation of Selective Caries Removal by a Fluorescence Feedback-Controlled Er:YAG Laser in vitro. Caries Res 2005; 39:496-504. [PMID: 16251795 DOI: 10.1159/000088186] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2004] [Accepted: 02/17/2005] [Indexed: 11/19/2022] Open
Abstract
AIM To establish a fluorescence threshold level that could guide a therapeutic Er:YAG laser through a caries lesion to determine a therapeutic endpoint of caries removal. MATERIALS AND METHODS A total of 65 extracted human teeth, 35 with dentine caries and 30 healthy, were used for this study. An Er:YAG laser system that emitted at a wavelength of 2.94 microm was used. The laser was equipped with a laser fluorescence feedback system, excitation wavelength 655 nm, to control the irradiation by the Er:YAG laser. The evaluated threshold levels of the fluorescence feedback system were 3, 7, 8, 10, 12, 15 and 20. After treatment the teeth were prepared for histological staining according to the method of Brown and Brenn for the identification of bacteria. The specimens were subjected to a quantitative evaluation of residual bacteria on the treated dentine surface. In addition, the internal fluorescence of dentine and potential fluorescence changes of dentine after laser irradiation were evaluated. RESULTS About 80% of the irradiated dentine surface showed residual bacteria with threshold levels of 20, 15, 12, and 10. Residual bacteria were not found with threshold levels of 7 and 3. The study revealed a significant increase in dentine fluorescence after laser irradiation. CONCLUSION The results of the present in vitro study indicate that a fluorescence threshold level of 7 or 8 units can guide an Er:YAG laser to a complete removal of carious dentine.
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Affiliation(s)
- J Eberhard
- Department of Operative Dentistry and Periodontology, University Hospital Schleswig-Holstein, Kiel, Germany.
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30
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Zinellu A, Sotgia S, Caddeo S, Deiana L, Carru C. Sodium glycylglycine as effective electrolyte run buffer for ascorbic and uric acid separation by CZE: A comparison with two other CE assays. J Sep Sci 2005; 28:2193-9. [PMID: 16318217 DOI: 10.1002/jssc.200500109] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A new CE method for ascorbic acid (AA) and uric acid (UA) detection in human plasma has been developed. Analytes were resolved in less than 4 min by employing sodium glycylglycine (Glygly) as electrolyte run buffer at pH 8.0. Using the diode array detector ability to measure multiple wavelengths simultaneously, detection was optimized by monitoring the run at 262 nm for AA and at 288 nm for UA. Electrophoretic parameters such as resolution, migration times, efficiency, and peak areas of this new method were compared to those obtained by the two CE assays described in literature, in which the analytes separation was achieved by using sodium borate (that allows faster migration times but poor resolution) or tricine (with the highest resolution but elevated migration times) as electrolyte run buffer. Sodium Glygly allows to obtain the same good resolution given by the tricine buffer but with the faster analysis times of the sodium borate run buffer. Ascorbate and urate levels were measured in 35 healthy volunteers by the three methods and the obtained data were compared by three different statistical tests (mountain plot, Passing-Bablok regression, and Bland-Altman test) in order to verify the accuracy of our proposed method.
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Affiliation(s)
- Angelo Zinellu
- Clinical Biochemistry, University of Sassari, Sassari, Italy
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31
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Powell PR, Ewing AG. Recent advances in the application of capillary electrophoresis to neuroscience. Anal Bioanal Chem 2005; 382:581-91. [PMID: 15726336 DOI: 10.1007/s00216-005-3075-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2004] [Revised: 12/29/2004] [Accepted: 01/17/2005] [Indexed: 05/01/2023]
Abstract
With fast separation times (seconds to minutes), minimal sample requirements (nanoliters to femtoliters), and excellent mass detection limits (femtomole to zeptomole), capillary electrophoresis (CE) is ideally suited for in vitro and in vivo sampling of neurological samples with a high degree of spatial resolution. Advances in extracellular fluid analysis employing improved microdialysis and push-pull perfusion sampling methodologies has enabled the resolution of neurotransmitters present in limited amounts using CE. Great progress has been made to resolve complex neuropeptides, amino acids, and biogenic amines in tissue and cell cultures. Finally, owing largely to the small volume sampling abilities of CE, investigations of single nerve cells, both invertebrate and mammalian, have been accomplished. These applications of CE to the advancement of neuroscience are presented.
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Affiliation(s)
- Paula R Powell
- Department of Chemistry, The Pennsylvania State University, 104 Chemistry Building, University Park, PA 16802, USA
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32
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Ohyama K, Wada M, Lord GA, Ohba Y, Nakashima MN, Nakashima K, Akiyama S, Lim CK, Kuroda N. Capillary electrochromatography of caffeine and its metabolites in rat brain microdialysate. Electrophoresis 2005; 26:812-817. [PMID: 15714566 DOI: 10.1002/elps.200410292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A capillary electrochromatography (CEC) method has been developed for the separation of caffeine and its two metabolites 1-methylxanthine (1-MX) and 1,7-dimethylxanthine (1,7-DX). The stationary phase was 3-(1,8-naphthalimido) propyl-modified silyl silica gel (NAIP) and the best separations were achieved with 4.0 mM citrate buffer (pH 5.0) containing 80% methanol at an applied voltage of 25 kV. The compounds were completely separated in less than 3.5 min with good repeatability, which was approximately 3-times less than that in high-performance liquid chromatography (HPLC) with NAIP. The proposed method coupled with microdialysis was successfully applied to the monitoring of caffeine concentration in rat brain with detection limits of 1.11 microg/mL.
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Affiliation(s)
- Kaname Ohyama
- Graduate School of Biomedical Sciences, Course of Pharmaceutical Sciences, Nagasaki University, Nagasaki, Japan
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Zinellu A, Carru C, Sotgia S, Deiana L. Optimization of ascorbic and uric acid separation in human plasma by free zone capillary electrophoresis ultraviolet detection. Anal Biochem 2004; 330:298-305. [PMID: 15203336 DOI: 10.1016/j.ab.2004.04.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2004] [Indexed: 02/04/2023]
Abstract
In this paper we propose a new fast free zone capillary electrophoresis method for the simultaneous determination of ascorbic acid (AA) and uric acid (UA) in human plasma. We investigated the effect of analytical parameters, such as concentration and pH of borate running buffer, cartridge temperature, and sample treatment, on resolution, migration times, corrected peak areas, and efficiency. A good separation was achieved using a 60.2-cmx75-microm uncoated silica capillary and 100 mmol/L sodium borate buffer, pH 8, when metaphosphoric acid was employed as protein precipitant, in less than 4 min. These conditions gave a good reproducibility of migration times (CV 0.35 and 0.34%) and peak areas (CV 3.2 and 3.1%) for ascorbate and urate, respectively. The limit of detection was 0.5mg/L for both analytes when the detection was performed at 254 nm for AA and at 292 nm for UA. We compared the present method with a validated capillary electrophoresis assay by measuring plasma urate and ascorbate in 32 normal subjects and the obtained data were analyzed by the Passing and Bablok regression.
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Affiliation(s)
- Angelo Zinellu
- Chair of Clinical Biochemistry, University of Sassari, 07100 Sassari, Italy
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Horstkötter C, Schepmann D, Blaschke G. Separation and identification of zaleplon metabolites in human urine using capillary electrophoresis with laser-induced fluorescence detection and liquid chromatography–mass spectrometry. J Chromatogr A 2003; 1014:71-81. [PMID: 14558613 DOI: 10.1016/s0021-9673(03)00564-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A capillary electrophoresis (CE) method using laser-induced fluorescence (LIF) detection for the determination of the hypnotic drug zaleplon and its metabolites in human urine could be developed using carboxymethyl-beta-cyclodextrin as a charged carrier. By the help of a complementary HPLC method coupled to mass spectrometry, three metabolites present in human urine could be identified as 5-oxozaleplon, 5-oxo-N-deethylzaleplon and 5-oxozaleplon glucuronide. N-Deethylzaleplon, a previously described zaleplon metabolite, as well as zaleplon itself could not be detected in human urine by the CE-LIF assay. The results were confirmed by spiking with reference compounds of the phase I metabolites. The metabolites differed very much concerning their fluorescence intensities, thus the 5-oxo metabolites present as lactam tautomer fluoresced tenfold lower than the unchanged drug zaleplon and its N-deethylated metabolite. The glucuronide of the 5-oxozaleplon, however, showed high fluorescence due to its lactim structure. Limits of quantification yielded by the CE-LIF assay including a ten-fold preconcentration step by solid-phase extraction were 10 ng/ml for zaleplon and N-deethylzaleplon and 100 ng/ml for 5-oxozaleplon and 5-oxo-N-deethylzaleplon.
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Affiliation(s)
- Christian Horstkötter
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Hittorfstrasse 58-62, D-48149 Münster, Germany
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35
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Sano M, Ueno K, Kamimori H. Enzyme assay for protein kinase using micellar electrokinetic chromatography with laser-induced fluorescence detection. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 794:149-56. [PMID: 12888207 DOI: 10.1016/s1570-0232(03)00450-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Micellar electrokinetic chromatography (MEKC) with laser-induced fluorescence (LIF) detection has been developed for a protein kinase assay. This protein kinase assay could readily determine the phosphorylation activity of substrate peptide kemptide using cAMP-dependent protein kinase (PKA) as a model enzyme. Kemptide and phosphorylated kemptide could be reacted with 7-fluoro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-F) as a fluorescence derivatization reagent for LIF detection by directly adding NBD-F into the PKA enzymatic reaction mixture. These derivatives of substrate and product were separated and detected within the analysis time of 5 min by micellar electrokinetic mode using a mixture of sodium dodecylsulfate and methanol as a running buffer. Good linearity of the peak response of the phosphorylated kemptide was obtained over the range of 1-20 mU/tube of PKA in the assay. The relative standard deviation of the peak areas of the phosphorylated kemptide using 2, 5 and 10 mU/tube of PKA were calculated to <10.4%, indicating that the assay was reproducible. Also, IC(50) values of six PKA inhibitors, the K(i) value and the inhibition pattern of one inhibitor, which were calculated to estimate by the variation of the peak area of the phosphorylated kemptide using 5 mU/tube of PKA, were consistent with the published data. The sensitivity of the assay was higher than that of enzyme-linked immunosorbent assay (ELISA) for PKA phosphorylation activity, as IC(50) values, K(i) value, and the inhibition mechanism of inhibitors could be estimated using one-tenth amounts of PKA, compared with that of ELISA. The MEKC-LIF is expected to be very useful for protein kinase assay and its application to the estimation of inhibitors because this method does not entail experimentally troublesome procedures such as the preparation of antibody or fluorescence-labeled substrate.
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Affiliation(s)
- Masatake Sano
- Shionogi Research Laboratories, Shionogi & Co, Ltd, 12-4, Sagisu-5-Chome, Fukushima-ku, Osaka 553-0002, Japan.
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36
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Lin YW, Chiu TC, Chang HT. Laser-induced fluorescence technique for DNA and proteins separated by capillary electrophoresis. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 793:37-48. [PMID: 12880853 DOI: 10.1016/s1570-0232(03)00363-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recent developments in capillary electrophoresis (CE) in conjunction with laser-induced fluorescence (LIF) using long-wavelength (maximum excitation wavelength>500 nm) dyes are reviewed. These dyes are particularly of interest when conducting the analyses of biopolymers by CE-LIF using He-Ne lasers. These systems are benefited from low background, low costs, easy maintenance, and compactness. Derivatizations of DNA and proteins with fluorescent or nonfluorescent chemicals can be carried out prior to, during, or after separations. With the advantages of sensitivity, rapidity, and high efficiency, the applications of CE-LIF to the analysis of polymerase chain reaction products, DNA sequencing, trace analysis of proteins, and single cell analysis have been presented.
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Affiliation(s)
- Yang-Wei Lin
- Department of Chemistry, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei, Taiwan
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37
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Kelly RT, Woolley AT. Thermal bonding of polymeric capillary electrophoresis microdevices in water. Anal Chem 2003; 75:1941-5. [PMID: 12713054 DOI: 10.1021/ac0262964] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new method for thermally bonding poly(methyl methacrylate) (PMMA) substrates to form microfluidic systems has been demonstrated. A PMMA substrate is first imprinted with a Si template using applied pressure and elevated temperature to form microchannel structures. This embossing method has been used to successfully pattern over 65 PMMA pieces using a single Si template. Thermal bonding for channel enclosure is accomplished by clamping together an imprinted and a blank substrate and placing the assembly in boiling water for 1 h. The functionality of these water-bonded microfluidic substrates was demonstrated by performing high-resolution electrophoretic separations of fluorescently labeled amino acids. Testing of bond strength in four microdevices showed an average failure pressure of 130 kPa, which was comparable to the bond strength for devices sealed in air. Subsequent profilometry of separated substrates revealed that the dimensions of the channels were well preserved during the bonding process. This new methodology for generation of microfluidic constructs should facilitate the permanent incorporation of hydrated, molecular size-selective membranes in microdevices, thus circumventing problems associated with membrane swelling in microfluidic systems upon exposure to water.
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Affiliation(s)
- Ryan T Kelly
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA
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Fukushima T, Usui N, Santa T, Imai K. Recent progress in derivatization methods for LC and CE analysis. J Pharm Biomed Anal 2003; 30:1655-87. [PMID: 12485710 DOI: 10.1016/s0731-7085(02)00511-3] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The derivatization procedure with a suitable fluorescence or chemiluminescence reagent is performed for the purpose of increasing the detection sensitivity and selectivity, in high-performance liquid chromatography (HPLC) and/or capillary electrophoresis (CE). In this article, recent derivatization methods and their applications to biosamples are described. In HPLC, femto mol order of mass detection limits are obtained by derivatization. Regarding the fluorescence reagents, the use of water-soluble reagents has been effective to avoid an undesired adsorption in the process of determination of peptides. In CE, the advantages of having extremely low mass detection limits (ranging from atto to yocto mol level) and requiring only a very short analysis time (less than a few minutes) are made possible by using laser-induced fluorescence or near infra-red detections.
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Affiliation(s)
- Takeshi Fukushima
- Laboratory of Bio-Analytical Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Wetterhall M, Palmblad M, Håkansson P, Markides KE, Bergquist J. Rapid analysis of tryptically digested cerebrospinal fluid using capillary electrophoresis-electrospray ionization-Fourier transform ion cyclotron resonance-mass spectrometry. J Proteome Res 2002; 1:361-6. [PMID: 12645892 DOI: 10.1021/pr025526s] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mass spectrometry has in recent years been established as the method of choice for protein identification and characterization in proteomics. Capillary electrophoresis (CE) is a fast and efficient method for the separation of peptides and proteins. The on-line combination of CE with Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS) has been shown to be a powerful tool in the analysis of complex mixtures of proteins. This paper presents the first results from a proteomic analysis of human cerebrospinal fluid proteins by tryptic digestion and CE-FTICR-MS, where 30 proteins could be identified on a 95% confidence level with mass measurement errors less than 5 ppm.
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Affiliation(s)
- Magnus Wetterhall
- Institute of Chemistry, Department of Analytical Chemistry, Uppsala University, PO Box 531, SE-751 21 Uppsala, Sweden
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