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Khan MS, Asif A, Khawaldeh S, Tekin A. Dopamine Detection using Mercaptopropionic Acid and Cysteamine for Electrodes Surface Modification. JOURNAL OF ELECTRICAL BIOIMPEDANCE 2018; 9:3-9. [PMID: 33584914 PMCID: PMC7852013 DOI: 10.2478/joeb-2018-0002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Indexed: 06/12/2023]
Abstract
Gold electrodes are often not suitable for dopamine measurements as dopamine creates a non-conducting polymer layer on the surface of the electrodes, which leads to increased amount of electrode passivity with the gradual increase in voltammograms measurement. This work presents the impedance spectroscopy and cyclic-voltammetry comparative study for dopamine detection with two modifications for the surface of Au electrodes; cysteamine and mercaptopropionic acid for thermally bonded and ultrasonically welded microfluidic chips, respectively. The effects of optimized tubing selection, bonding techniques, and cleaning methods of the devices with KOH solution played crucial role for improvements in dopamine detection, which are observed in the results. Furthermore, comparison for the modification with unmodified chips, and finding the unknown concentration of dopamine solution using flow injection techniques, is also illustrated.
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Affiliation(s)
- Muhammad Salman Khan
- Graduate School of Engineering and Science, Ozyegin University, Istanbul, Turkey
| | - Afia Asif
- Graduate School of Engineering and Science, Ozyegin University, Istanbul, Turkey
| | - Saed Khawaldeh
- Erasmus+ Joint Master Program in Medical Imaging and Applications, University of Girona, Girona, Spain
- Erasmus+ Joint Master Program in Medical Imaging and Applications, University of Burgundy, Dijon, France
- Erasmus+ Joint Master Program in Medical Imaging and Applications, UNICLAM, CassinoFR, Italy
| | - Ahmet Tekin
- Graduate School of Engineering and Science, Ozyegin University, Istanbul, Turkey
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Sun S, Buer BC, Marsh ENG, Kennedy RT. A Label-free Sirtuin 1 Assay based on Droplet-Electrospray Ionization Mass Spectrometry. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2016; 8:3458-3465. [PMID: 27482292 PMCID: PMC4962873 DOI: 10.1039/c6ay00698a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Sirtuin 1(SIRT1) is a NAD+-dependent deacetylase which has been implicated in age-related diseases such as cancer, Alzheimer's disease, type 2 diabetes, and vascular diseases. SIRT1 modulators are of interest for their potential therapeutic use and potential as chemical probes to study the role of SIRT1. Fluorescence-based assays used to identify SIRT1 activators have been shown to have artifacts related to the fluorophore substrates used in the assays. Such problems highlight the potential utility of a label-free high throughput screening (HTS) strategy. In this work, we describe a label-free SIRT1 assay suitable for HTS based on segmented flow-electrospray ionization-mass spectrometry (ESI-MS). In the assay, 0.5 μM SIRT1 was incubated with 20 μM acetylated 21-amino acid peptide, which acts as substrate for the protein. A stable-isotope labeled product peptide was added to the assay mixture as an internal standard after reaction quenching. The resulting samples are formatted into 100 nL droplets segmented by perfluorodecalin and then infused at 0.8 samples/s into an ESI-MS. To enable direct ESI-MS analysis, 11 μM SIRT1 was dialyzed into a 200 μM ammonium formate (pH 8.0) buffer prior to use in the assay. This buffer was demonstrated to minimally affect enzyme kinetics and yet be compatible with ESI-MS. The assay conditions were optimized through enzyme kinetic study, and tested by screening an 80-compound library. The assay Z-factor was 0.7. Four inhibitors and no activators were detected from the library.
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Affiliation(s)
- Shuwen Sun
- University of Michigan, Department of Chemistry, Ann Arbor, Michigan, 48109, United States
| | - Benjamin C. Buer
- University of Michigan, Department of Chemistry, Ann Arbor, Michigan, 48109, United States
| | - E. Neil G. Marsh
- University of Michigan, Department of Chemistry, Ann Arbor, Michigan, 48109, United States
- University of Michigan, Department of Biological Chemistry, Ann Arbor, Michigan, 48109, United States
| | - Robert T. Kennedy
- University of Michigan, Department of Chemistry, Ann Arbor, Michigan, 48109, United States
- University of Michigan, Department of Pharmacology, Ann Arbor, Michigan, 48109, United States
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3
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A simpler sampling interface of venturi easy ambient sonic-spray ionization mass spectrometry for high-throughput screening enzyme inhibitors. Anal Chim Acta 2016; 913:86-93. [DOI: 10.1016/j.aca.2016.01.051] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/28/2016] [Accepted: 01/29/2016] [Indexed: 12/11/2022]
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Sun S, Kennedy RT. Droplet electrospray ionization mass spectrometry for high throughput screening for enzyme inhibitors. Anal Chem 2014; 86:9309-14. [PMID: 25137241 PMCID: PMC4165461 DOI: 10.1021/ac502542z] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 08/19/2014] [Indexed: 12/20/2022]
Abstract
High throughput screening (HTS) is important for identifying molecules with desired properties. Mass spectrometry (MS) is potentially powerful for label-free HTS due to its high sensitivity, speed, and resolution. Segmented flow, where samples are manipulated as droplets separated by an immiscible fluid, is an intriguing format for high throughput MS because it can be used to reliably and precisely manipulate nanoliter volumes and can be directly coupled to electrospray ionization (ESI) MS for rapid analysis. In this study, we describe a "MS Plate Reader" that couples standard multiwell plate HTS workflow to droplet ESI-MS. The MS plate reader can reformat 3072 samples from eight 384-well plates into nanoliter droplets segmented by an immiscible oil at 4.5 samples/s and sequentially analyze them by MS at 2 samples/s. Using the system, a label-free screen for cathepsin B modulators against 1280 chemicals was completed in 45 min with a high Z-factor (>0.72) and no false positives (24 of 24 hits confirmed). The assay revealed 11 structures not previously linked to cathepsin inhibition. For even larger scale screening, reformatting and analysis could be conducted simultaneously, which would enable more than 145,000 samples to be analyzed in 1 day.
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Affiliation(s)
- Shuwen Sun
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Robert T. Kennedy
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, United States
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Sott K, Eriksson E, Petelenz E, Goksör M. Optical systems for single cell analyses. Expert Opin Drug Discov 2013; 3:1323-44. [PMID: 23496168 DOI: 10.1517/17460441.3.11.1323] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Data extracted from a population of cells represent the average response from all cells within the population. Even when the cells are genetically identical, cell-to-cell variations and genetic noise can make the cells respond in completely different ways. To understand the mechanisms behind the behaviour of a population, the cells must also be analysed on an individual basis. OBJECTIVE This review highlights the use of optical manipulation, microfluidics and advanced fluorescence imaging techniques for the acquisition of single cell data. CONCLUSION By implementation of these three techniques, it is possible to achieve a deeper insight into the principles underlying cellular functioning and a more thorough understanding of the phenomena often observed in cell populations, thus facilitating research in drug discovery.
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Affiliation(s)
- Kristin Sott
- Postdoctoral fellow University of Gothenburg, Department of Physics, SE-41296, Gothenburg, Sweden
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Deng XJ, Yang HQ, Li JZ, Song Y, Guo DH, Luo Y, Du XN, Bo T. MULTICLASS RESIDUES SCREENING OF 105 VETERINARY DRUGS IN MEAT, MILK, AND EGG USING ULTRA HIGH PERFORMANCE LIQUID CHROMATOGRAPHY TANDEM QUADRUPOLE TIME-OF-FLIGHT MASS SPECTROMETRY. J LIQ CHROMATOGR R T 2011. [DOI: 10.1080/10826076.2011.587224] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Affiliation(s)
- Xiao-Jun Deng
- a Shanghai Entry-Exit Inspection and Quarantine Bureau of The People's Republic of China , Shanghai, P.R. China
| | - Hui-Qin Yang
- a Shanghai Entry-Exit Inspection and Quarantine Bureau of The People's Republic of China , Shanghai, P.R. China
| | | | - Yue Song
- b Agilent Technologies , Beijing, P.R. China
| | - De-Hua Guo
- a Shanghai Entry-Exit Inspection and Quarantine Bureau of The People's Republic of China , Shanghai, P.R. China
| | - Yong Luo
- c Shanghai Research Institute of Chemical Industry , Shanghai, P.R. China
| | - Xiao-Ning Du
- c Shanghai Research Institute of Chemical Industry , Shanghai, P.R. China
| | - Tao Bo
- b Agilent Technologies , Beijing, P.R. China
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Yuliana ND, Khatib A, Choi YH, Verpoorte R. Metabolomics for bioactivity assessment of natural products. Phytother Res 2011; 25:157-69. [PMID: 20658470 DOI: 10.1002/ptr.3258] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Natural products historically have been a rich source of lead molecules in drug discovery, based on their capability to create unique and diverse chemical structures. However, it is also true that the vast number of metabolites typically present in natural products and their huge dynamic range results in the loss of many possibly bioactive natural compounds, becoming an inextricable obstacle for drug development. Recently, new strategies which favour a holistic approach as opposed to the traditional reductionist methods used previously, have been introduced with the purpose of overcoming the bottlenecks in natural product research. This approach is based on the application of new technologies, including metabolomics, for example. Metabolomics allows a systematic study of a complex mixture such as a phytochemical preparation, which can be linked to observations obtained through biological testing systems without the need for isolating active principles. This may put drug discovery from natural products back in the limelight again. In this review paper, the description of some examples of successful metabolomics applications in several important fields related to drug discovery from natural sources aims at raising the potential of metabolomics in reducing the gap between natural products (NP) and modern drug discovery demand.
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Affiliation(s)
- Nancy Dewi Yuliana
- Division of Pharmacognosy, Section of Metabolomics, Institute of Biology, Leiden University, Leiden, The Netherlands
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de la Guardia M, Armenta S. The Basis of a Greener Analytical Chemistry. GREEN ANALYTICAL CHEMISTRY 2011. [DOI: 10.1016/b978-0-444-53709-6.00002-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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9
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Yeon JH, Park JK. Drug permeability assay using microhole-trapped cells in a microfluidic device. Anal Chem 2010; 81:1944-51. [PMID: 19203200 DOI: 10.1021/ac802351w] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
As orally administered drugs must be absorbed from the intestine into the blood circulation, permeability assays of drug candidates have been widely used in the early screening stages of drug discovery. In this study, a microfluidic device was developed for the drug permeability assay, considering the in vivo delivery path of drugs in humans. A microhole array for cell trapping was fabricated using the poly(dimethylsiloxane) (PDMS) molding technique by mimicking the intestinal epithelial cell membrane. On the basis of mathematical simulations, the configuration of the microfluidic device, including a microhole array and a mixing channel, was optimized to trap cells firmly in each microhole. At the flow rate under optimal conditions, cells were effectively trapped in a microhole array without cell damage. We measured the permeability of 10 drugs, including those with high and low permeability in microchannels, and compared the results with the reported values of permeability in the human and rat intestine. Most drugs had a high p value (p > 0.4), and only a few drugs had a low p value less than 0.05 by t test. Though their measured permeabilities are not the same as those in vivo human intestine, it shows that in vivo permeabilities in the human and rat intestine are highly correlated with those measured by the microfluidic device (R(2) = 0.9013 and R(2) = 0.8765, respectively). Also, the fraction of the dose absorbed in the human intestine (F(a)) indicated that the drug permeability measured using this device was significantly correlated (R(2) = 0.9641) with those in human subjects. As the microfluidic assay system is dependent on cells trapped inside a microhole array, it is a valuable tool in drug discovery as well as an alternative to animal testing.
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Affiliation(s)
- Ju Hun Yeon
- Department of Bio and Brain Engineering, College of Life Science and Bioengineering, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, Republic of Korea
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Pei J, Li Q, Kennedy RT. Rapid and label-free screening of enzyme inhibitors using segmented flow electrospray ionization mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:1107-1113. [PMID: 20219390 DOI: 10.1016/j.jasms.2010.02.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 02/05/2010] [Accepted: 02/07/2010] [Indexed: 05/28/2023]
Abstract
Electrospray ionization mass spectrometry (ESI-MS) is an attractive analytical tool for high-throughput screening because of its rapid scan time and ability to detect compounds without need for labels. Impediments to the use of ESI-MS for screening have been the relatively large sample consumed and slow sample introduction rates associated with commonly used flow injection analysis. We have previously shown that by segmenting nanoliter plugs of sample with air, an array of discrete samples can be delivered to a platinum-coated emitter tip for ESI-MS analysis with throughput as high as 0.8 Hz and carry-over between samples less than 0.1%. This method was applied to screening for inhibitors of acetylcholinesterase as a demonstration of the potential of segmented flow ESI-MS for such applications. Each enzyme assay consumed 10 nL of sample. At 1 microL/min infusion rate, 102 samples were analyzed, corresponding to a 0.65 Hz sample analysis rate. Linear quantification of choline was achieved from 200 microM to 10 mM using this method and Z' values were over 0.8 for the assay. Detailed pharmacologic dose-response curves of selected inhibitors were also measured in high-throughput fashion to validate the method.
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Affiliation(s)
- Jian Pei
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
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11
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High-throughput in vivo screening of targeted molecular imaging agents. Proc Natl Acad Sci U S A 2009; 106:17904-9. [PMID: 19815497 DOI: 10.1073/pnas.0906925106] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The rapid development and translation of targeted molecular imaging agents from bench to bedside is currently a slow process, with a clear bottleneck between the discovery of new compounds and the development of an appropriate molecular imaging agent. The ability to identify promising new molecular imaging agents, as well as failures, much earlier in the development process using high-throughput screening techniques could save significant time and money. This work combines the advantages of combinatorial chemistry, site-specific solid-phase radiolabeling, and in vivo imaging for the rapid screening of molecular imaging agents. A one-bead-one-compound library was prepared and evaluated in vitro, leading to the identification of 42 promising lead peptides. Over 11 consecutive days, these peptides, along with a control peptide, were successfully radiolabeled with 4-[(18)F]fluorobenzoic acid and evaluated in vivo using microPET. Four peptides were radiolabeled per day, followed by simultaneous injection of each individual peptide into 2 animals. As a result, 4 promising new molecular imaging agents were identified that otherwise would not have been selected based solely on in vitro data. This study is the first example of the practical application of a high-throughput screening approach using microPET imaging of [(18)F]-labeled peptides for the rapid in vivo identification of potential new molecular imaging agents.
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Saunders KC, Ghanem A, Boon Hon W, Hilder EF, Haddad PR. Separation and sample pre-treatment in bioanalysis using monolithic phases: A review. Anal Chim Acta 2009; 652:22-31. [DOI: 10.1016/j.aca.2009.05.043] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 05/29/2009] [Accepted: 05/30/2009] [Indexed: 10/20/2022]
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13
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Kostesha N, Heiskanen A, Spégel C, Hahn-Hägerdal B, Gorwa-Grauslund MF, Emnéus J. Real-time detection of cofactor availability in genetically modified living Saccharomyces cerevisiae cells — Simultaneous probing of different geno- and phenotypes. Bioelectrochemistry 2009; 76:180-8. [DOI: 10.1016/j.bioelechem.2009.02.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2008] [Revised: 02/23/2009] [Accepted: 02/27/2009] [Indexed: 10/21/2022]
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Affiliation(s)
- Eu Vian Tan
- Institute of Biotechnology, Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QT, U.K
| | - Christopher R. Lowe
- Institute of Biotechnology, Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QT, U.K
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15
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Schoonen WGEJ, Westerink WMA, Horbach GJ. High-throughput screening for analysis of in vitro toxicity. EXS 2009; 99:401-52. [PMID: 19157069 DOI: 10.1007/978-3-7643-8336-7_14] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The influence of combinatorial chemistry and high-throughput screening (HTS) technologies in the pharmaceutical industry during the last 10 years has been enormous. However, the attrition rate of drugs in the clinic due to toxicity during this period still remained 40-50%. The need for reduced toxicity failure led to the development of early toxicity screening assays. This chapter describes the state of the art for assays in the area of genotoxicity, cytotoxicity, carcinogenicity, induction of specific enzymes from phase I and II metabolism, competition assays for enzymes of phase I and II metabolism, embryotoxicity as well as endocrine disruption and reprotoxicity. With respect to genotoxicity, the full Ames, Ames II, Vitotox, GreenScreen GC, RadarScreen, and non-genotoxic carcinogenicity assays are discussed. For cytotoxicity, cellular proliferation, calcein uptake, oxygen consumption, mitochondrial activity, radical formation, glutathione depletion as well as apoptosis are described. For high-content screening (HCS), the possibilities for analysis of cytotoxicity, micronuclei, centrosome formation and phospholipidosis are examined. For embryotoxicity, endocrine disruption and reprotoxicity alternative assays are reviewed for fast track analysis by means of nuclear receptors and membrane receptors. Moreover, solutions for analyzing enzyme induction by activation of nuclear receptors, like AhR, CAR, PXR, PPAR, FXR, LXR, TR and RAR are given.
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Heiskanen A, Spégel C, Kostesha N, Lindahl S, Ruzgas T, Emnéus J. Mediator-assisted simultaneous probing of cytosolic and mitochondrial redox activity in living cells. Anal Biochem 2008; 384:11-9. [PMID: 18812160 DOI: 10.1016/j.ab.2008.08.030] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 08/12/2008] [Accepted: 08/28/2008] [Indexed: 11/16/2022]
Abstract
This work describes an electron transfer mediator-assisted amperometric flow injection method for assessing redox enzyme activity in different subcellular compartments of the phosphoglucose isomerase deletion mutant strain of Saccharomyces cerevisiae, EBY44. The method is demonstrated using the ferricyanide-menadione double mediator system to study the effect of dicoumarol, an inhibitor of cytosolic and mitochondrial oxidoreductases and an uncoupler of the electron transport chain. Evaluation of the role of NAD(P)H-producing pathways in mediating biological effects is facilitated by introducing either fructose or glucose as the carbon source, yielding either NADH or NADPH through the glycolytic or pentose phosphate pathway, respectively. Respiratory noncompetent cells show greater inhibition of cytosolic menadione-reducing enzymes when NADH rather than NADPH is produced. Spectrophotometric in vitro assays show no difference between the cofactors. Respiratory competent cells show cytosolic inhibition only when NADPH is produced, whereas production of NADH reveals uncoupling at low dicoumarol concentrations and inhibition of complexes III and IV at higher concentrations. Spectrophotometric assays only indicate the presence of cytosolic inhibition regardless of the reduced cofactor used. This article shows the applicability of the amperometric method and emphasizes the significance of determining biological effects of chemicals in living cells.
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Affiliation(s)
- Arto Heiskanen
- Department of Analytical Chemistry, Lund University, SE-22100 Lund, Sweden; DTU Nanotech-Department of Micro and Nanotechnology, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
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Heiskanen AR, Spégel CF, Kostesha N, Ruzgas T, Emnéus J. Monitoring of Saccharomyces cerevisiae cell proliferation on thiol-modified planar gold microelectrodes using impedance spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:9066-9073. [PMID: 18630975 DOI: 10.1021/la800580f] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
An impedance spectroscopic study of the interaction between thiol-modified Au electrodes and Saccharomyces cerevisiae of strain EBY44 revealed that the cells formed an integral part of the interface, modulating the capacitive properties until a complete monolayer was obtained, whereas the charge transfer resistance ( R ct) to the redox process of [Fe(CN)6] 3-/4- showed a linear relationship to the number of cells even beyond the monolayer coverage. R ct showed strong pH dependence upon increasing the pH of the utilized buffer to 7.2. Upon addition of S. cerevisiae cells at pH 7.2, the obtained value of R ct showed over 560% increase with respect to the value obtained on the same thiol-modified electrode without cells. It was demonstrated that real-time monitoring of S. cerevisiae proliferation, with frequency-normalized imaginary admittance (real capacitance) as the indicator, was possible using a miniaturized culture system, ECIS Cultureware, with integrated planar cysteamine-modified Au microelectrodes. A monolayer coverage was reached after 20-28 h of cultivation, observed as an approximately 15% decrease in the real capacitance of the system.
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Affiliation(s)
- Arto R Heiskanen
- Department of Analytical Chemistry, Lund University, PO Box 124, Lund, Sweden
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Santos-Neto AJ, Bergquist J, Lanças FM, Sjöberg PJ. Simultaneous analysis of five antidepressant drugs using direct injection of biofluids in a capillary restricted-access media-liquid chromatography–tandem mass spectrometry system. J Chromatogr A 2008; 1189:514-22. [DOI: 10.1016/j.chroma.2008.02.107] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 02/14/2008] [Accepted: 02/19/2008] [Indexed: 10/22/2022]
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