Two New Devices for Identifying Electrochemical Reaction
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Supplementary Information
Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A This journal is © The Royal Society of Chemistry 2012 Supplementary Information 1. Synthesize the redox couples. The synthesis started commercially from available isothiocyanate which were transformed into the corresponding 1-ethyl-1H-tetrazole-5-thiol (ET) derivatives by cycloaddition reaction with sodium azide in refluxing ethanol according to the known procedures. Then the oxidized specie, bis(1-ethyltetrazol-5-yl) (BET) disulfides, was prepared by oxidation of the corresponding ET with hydrogen peroxide, and thiolate (ET-) form was obtained by deprotonation of the corresponding mercaptan (ET) with sodium bicarbonate. The structures of the above-mentioned redox couple was proved by the combination of 1HNMR spectroscopy, mass spectroscopy (ESI-MS) and elemental analyses. The NMR spectra were recorded at 298 K in CDCl3 at 300 MHz on a Varian Mercury-VX300 spectrometer. The chemical shifts were recorded in parts per million (ppm) with TMS as the internal reference. ESI mass spectra were determined using Finnigan LCQ Advantage mass spectrometer. Elemental analyses were performed with Thermo Quest Flash EA1112. The electrolyte consisted of 0.4 M of ET-, 0.05 M of BET, 0.4 M 18-crown-6 (18-C-6), 0.05 M LiClO4 and 0.5 M 4-tert-butylpyridine (TBP) in acetonitrile (ACN). 2. Preparation of electrodes. The NiS electrodes were electrodeposited onto a fluorine-doped tin oxide (FTO) glass substrate (13Ω/□) from an aqueous electrolyte consisting of 1M CH4N2S and 40mM NiCl2∙6H2O in a single-compartment glass cell with three-electrode configuration using electrochemical work station. -
Mass Spectrometer Business Presentation Materials
Mass Spectrometer Business Presentation Materials Hiroto Itoi, Corporate Officer Deputy General Manager of the Analytical & Measuring Instruments Division Shimadzu Corporation Jul. 3, 2018 Contents I. Introduction • Expansion of Mass Spectrometry ………………………………………………………………… p.3 • History of Shimadzu's Growth in Mass Spectrometry …………………………………………… p.5 II. Overview of Mass Spectrometers • Operating Principle, Demand Trends, and Vendors ……………………………………………… p.9 • Mass Spectra ………………………………………………………………………………………… p.10 • Configuration of Mass Spectrometers …………………………………………………………… p.11 • Ionization …………………………………………………………………………………………… p.12 • Mass Separation …………………………………………………………………………………… p.14 III. Shimadzu's Mass Spectrometer Business • Product Type ………………………………………………………………………………………… p.17 • Application Software ………………………………………………………………………………… p.18 • Growth Strategy for Mass Spectrometer Business ……………………………………………… p.19 • Expand/Improve Product Lines …………………………………………………………………… p.20 • Measures to Expand Application Fields …………………………………………………………… p.24 • Measures to Automate Data Processing Using AI ……………………………………………… p.25 IV. Summary • Future Direction ……………………………………………………………………………………… p.26 July 2018 Mass Spectrometer Business Presentation Materials 2 I. Introduction Expansion of Mass Spectrometry (1) Why Mass Spectrometry? Mass spectrometry is able to analyze a wide variety of compounds with high accuracy and high efficiency (simultaneous multicomponent analysis). It offers superior characteristics that are especially beneficial in the following fields, -
Physical and Analytical Electrochemistry: the Fundamental
Electrochemical Systems The simplest and traditional electrochemical process occurring at the boundary between an electronically conducting phase (the electrode) and an ionically conducting phase (the electrolyte solution), is the heterogeneous electro-transfer step between the electrode and the electroactive species of interest present in the solution. An example is the plating of nickel. Ni2+ + 2e- → Ni Physical and Analytical The interface is where the action occurs but connected to that central event are various processes that can Electrochemistry: occur in parallel or series. Figure 2 demonstrates a more complex interface; it represents a molecular scale snapshot The Fundamental Core of an interface that exists in a fuel cell with a solid polymer (capable of conducting H+) as an electrolyte. of Electrochemistry However, there is more to an electrochemical system than a single by Tom Zawodzinski, Shelley Minteer, interface. An entire circuit must be made and Gessie Brisard for measurable current to flow. This circuit consists of the electrochemical cell plus external wiring and circuitry The common event for all electrochemical processes is that (power sources, measuring devices, of electron transfer between chemical species; or between an etc). The cell consists of (at least) electrode and a chemical species situated in the vicinity of the two electrodes separated by (at least) one electrolyte solution. Figure 3 is electrode, usually a pure metal or an alloy. The location where a schematic of a simple circuit. Each the electron transfer reactions take place is of fundamental electrode has an interface with a importance in electrochemistry because it regulates the solution. Electrons flow in the external behavior of most electrochemical systems. -
Contents • Introduction to Proteomics and Mass Spectrometry
Contents • Introduction to Proteomics and Mass spectrometry - What we need to know in our quest to explain life - Fundamental things you need to know about mass spectrometry • Interfaces and ion sources - Electrospray ionization (ESI) - conventional and nanospray - Heated nebulizer atmospheric pressure chemical ionization - Matrix assisted laser desorption • Types of MS analyzers - Magnetic sector - Quadrupole - Time-of-flight - Hybrid - Ion trap In the next step in our quest to explain what is life The human genome project has largely been completed and many other genomes are surrendering to the gene sequencers. However, all this knowledge does not give us the information that is needed to explain how living cells work. To do that, we need to study proteins. In 2002, mass spectrometry has developed to the point where it has the capacity to obtain the "exact" molecular weight of many macromolecules. At the present time, this includes proteins up to 150,000 Da. Proteins of higher molecular weights (up to 500,000 Da) can also be studied by mass spectrometry, but with less accuracy. The paradigm for sequencing of peptides and identification of proteins has changed – because of the availability of the human genome database, peptides can be identified merely by their masses or by partial sequence information, often in minutes, not hours. This new capacity is shifting the emphasis of biomedical research back to the functional aspects of cell biochemistry, the expression of particular sets of genes and their gene products, the proteins of the cell. These are the new goals of the biological scientist: o to know which proteins are expressed in each cell, preferably one cell at a time o to know how these proteins are modified, information that cannot necessarily be deduced from the nucleotide sequence of individual genes. -
And the Reference Electrode (Right)
Development of an Electrochemical Sensor for Detection of 2,4-Dinitrotoluene A DISSERTATION SUBMITTED TO THE FACULTY OF THE GRADUATE SCHOOL OF THE UNIVERSITY OF MINNESOTA BY Eric James Olson IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Philippe Bühlmann, Adviser July 2012 © Eric J. Olson 2012 Acknowledgements During the course of my doctoral work, I have received the assistance and support from the following people: First and foremost, I am truly indebted to my adviser, Philippe Bühlmann. His undying dedication to science and insatiable thirst for knowledge has been an inspiration to me over the last five years. More than that, the guidance, support, and, most importantly, friendship that Phil has provided has greatly benefitted my development both as a person and as a scientist. I must give special thanks to Dr. Paul Boswell and Dr. Scott Thorgaard for helping me get started in the lab and teaching me best practices for performing electrochemistry experiments. I would also like to thank the following people for their specific contributions to the work described in this thesis: Our collaborator, Professor Andreas Stein, for the many hours that he has spent discussing our collaborative research. His insight and unique point of view has been extremely useful. Dr. Bradley Givot at the 3M Corporate Research Laboratory for measuring the dielectric spectra presented in Chapter 2. Dr. Letitia Yao of the University of Minnesota Chemistry NMR Lab for her assistance with measuring the self-diffusion coefficient of perfluoro(methylcyclohexane) in Chapter 2. Peter Ness of the University of Minnesota Physics Machine Shop for his assistance in designing the microcell described in Chapter 3. -
Modern Mass Spectrometry
Modern Mass Spectrometry MacMillan Group Meeting 2005 Sandra Lee Key References: E. Uggerud, S. Petrie, D. K. Bohme, F. Turecek, D. Schröder, H. Schwarz, D. Plattner, T. Wyttenbach, M. T. Bowers, P. B. Armentrout, S. A. Truger, T. Junker, G. Suizdak, Mark Brönstrup. Topics in Current Chemistry: Modern Mass Spectroscopy, pp. 1-302, 225. Springer-Verlag, Berlin, 2003. Current Topics in Organic Chemistry 2003, 15, 1503-1624 1 The Basics of Mass Spectroscopy ! Purpose Mass spectrometers use the difference in mass-to-charge ratio (m/z) of ionized atoms or molecules to separate them. Therefore, mass spectroscopy allows quantitation of atoms or molecules and provides structural information by the identification of distinctive fragmentation patterns. The general operation of a mass spectrometer is: "1. " create gas-phase ions "2. " separate the ions in space or time based on their mass-to-charge ratio "3. " measure the quantity of ions of each mass-to-charge ratio Ionization sources ! Instrumentation Chemical Ionisation (CI) Atmospheric Pressure CI!(APCI) Electron Impact!(EI) Electrospray Ionization!(ESI) SORTING DETECTION IONIZATION OF IONS OF IONS Fast Atom Bombardment (FAB) Field Desorption/Field Ionisation (FD/FI) Matrix Assisted Laser Desorption gaseous mass ion Ionisation!(MALDI) ion source analyzer transducer Thermospray Ionisation (TI) Analyzers quadrupoles vacuum signal Time-of-Flight (TOF) pump processor magnetic sectors 10-5– 10-8 torr Fourier transform and quadrupole ion traps inlet Detectors mass electron multiplier spectrum Faraday cup Ionization Sources: Classical Methods ! Electron Impact Ionization A beam of electrons passes through a gas-phase sample and collides with neutral analyte molcules (M) to produce a positively charged ion or a fragment ion. -
Characterization of a Microfabricated Electrochemical Detector and Coupling
UNIVERSITY OF CINCINNATI Date: 1-Oct-2009 I, Evan T Ogburn , hereby submit this original work as part of the requirements for the degree of: Master of Science in Chemistry It is entitled: Characterization of a Microfabricated Electrochemical Detector and Coupling with High Performance Liquid Chromatography Student Signature: Evan T Ogburn This work and its defense approved by: Committee Chair: William Heineman, PhD William Heineman, PhD Carl Seliskar, PhD Carl Seliskar, PhD 11/12/2009 288 Characterization of a Microfabricated Electrochemical Detector and Coupling with High Performance Liquid Chromatography A thesis submitted to the Division of Research & Advanced Studies of the University of Cincinnati In partial fulfillment of the requirements for the degree of Master of Science In the Department of Chemistry of the College of Arts and Sciences 2009 By Evan Ogburn B.A., Earlham College, 2005 Committee Chair: William R. Heineman, Ph.D. Abstract A disposable micro-fabricated electrochemical cell has been developed, characterized with multiple electrochemical systems, and coupled with high performance liquid chromatography to form a high performance liquid chromatography electrochemical detection (HPLC-ED) system. The detection system consisted of the micro-fabricated electrochemical detector, a flow-cell and a fixture mounted with electrical connections leading from the detector to the potentiostat. The detector is easy to fabricate, inexpensive, and maintains a high performance level which makes it a practical choice for electrochemical detection. The simplicity of the fabrication process for this detector allows it to be used as a disposable device that can be replaced easily if its performance degrades. Parameters for the optimization of the performance were studied in a three-electrode system with a special focus on HPLC-ED, using ascorbic acid, acetaminophen, and potassium ferricyanide as model compounds. -
Methods of Ion Generation
Chem. Rev. 2001, 101, 361−375 361 Methods of Ion Generation Marvin L. Vestal PE Biosystems, Framingham, Massachusetts 01701 Received May 24, 2000 Contents I. Introduction 361 II. Atomic Ions 362 A. Thermal Ionization 362 B. Spark Source 362 C. Plasma Sources 362 D. Glow Discharge 362 E. Inductively Coupled Plasma (ICP) 363 III. Molecular Ions from Volatile Samples. 364 A. Electron Ionization (EI) 364 B. Chemical Ionization (CI) 365 C. Photoionization (PI) 367 D. Field Ionization (FI) 367 IV. Molecular Ions from Nonvolatile Samples 367 Marvin L. Vestal received his B.S. and M.S. degrees, 1958 and 1960, A. Spray Techniques 367 respectively, in Engineering Sciences from Purdue Univesity, Layfayette, IN. In 1975 he received his Ph.D. degree in Chemical Physics from the B. Electrospray 367 University of Utah, Salt Lake City. From 1958 to 1960 he was a Scientist C. Desorption from Surfaces 369 at Johnston Laboratories, Inc., in Layfayette, IN. From 1960 to 1967 he D. High-Energy Particle Impact 369 became Senior Scientist at Johnston Laboratories, Inc., in Baltimore, MD. E. Low-Energy Particle Impact 370 From 1960 to 1962 he was a Graduate Student in the Department of Physics at John Hopkins University. From 1967 to 1970 he was Vice F. Low-Energy Impact with Liquid Surfaces 371 President at Scientific Research Instruments, Corp. in Baltimore, MD. From G. Flow FAB 371 1970 to 1975 he was a Graduate Student and Research Instructor at the H. Laser Ionization−MALDI 371 University of Utah, Salt Lake City. From 1976 to 1981 he became I. -
VAN BERKEL, 2005 BIEMANN MEDAL AWARDEE Expanded Use of a Battery-Powered Two-Electrode Emitter Cell for Electrospray Mass Spectrometry
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector FOCUS: VAN BERKEL, 2005 BIEMANN MEDAL AWARDEE Expanded Use of a Battery-Powered Two-Electrode Emitter Cell for Electrospray Mass Spectrometry Vilmos Kertesz and Gary J. Van Berkel Organic and Biological Mass Spectrometry Group, Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA A battery-powered, controlled-current, two-electrode electrochemical cell containing a porous flow-through working electrode with high surface area and multiple auxiliary electrodes with small total surface area was incorporated into the electrospray emitter circuit to control the electrochemical reactions of analytes in the electrospray emitter. This cell system provided the ability to control the extent of analyte oxidation in positive ion mode in the electrospray emitter by simply setting the magnitude and polarity of the current at the working electrode. In addition, this cell provided the ability to effectively reduce analytes in positive ion mode and oxidize analytes in negative ion mode. The small size, economics, and ease of use of such a battery-powered controlled-current emitter cell was demonstrated by powering a single resistor and switch circuit with a small-size, 3 V watch battery, all of which might be incorporated on the emitter cell. (J Am Soc Mass Spectrom 2006, 17, 953–961) © 2006 American Society for Mass Spectrometry lectrochemistry is an inherent part of the normal Basicprinciplesofelectrochemistrydictate[5]and -
A Novel High Resolution Accurate Mass Orbitrap-Based GC-MS
ROUTINE OR RESEARCH GC-Orbitrap for Environmental Analysis a collaboration between ROUTINE OR RESEARCH GC-Orbitrap for Environmental Analysis Foreword A Novel High Resolution Accurate Mass Orbitrap-based GC-MS Platform for Routine Analysis of Short Chained Chlorinated Paraffins In this study, the performance of a novel bench top, high resolution accurate mass Orbitrap™-based GC-MS was tested for the analysis of SCCPs. System performance was tested using full-scan acquisition and simple instrumental setup. Pyrolysis-GC-Orbitrap MS - A Powerful Analytical Tool for Identification and Quantification of Microplastics in a Biological Matrix The purpose of the experiments described in this work was to assess the applicability of pyrolysis-gas chromatography-Orbitrap™ mass spectrometry for the qualitative and quantitative analysis of plastic polymers in complex biological matrices. Low Level Quantification of NDMA and Non-targeted Contaminants Screening in Drinking Water using GC Orbitrap Mass Spectrometry In this work, a sensitive and selective method for NDMA detection and quantification using high resolution accurate mass GC Orbitrap™ technology is described. Overcoming Analytical Challenges for Polybrominated Diphenyl Ethers (PBDEs) Analysis in Environmental Samples using Gas Chromatography – Orbitrap Mass Spectrometry The note demonstrates the quantitative performance of the Thermo Scientific™ Exactive™ GC Orbitrap™ GC-MS mass spectrometer for the analysis of polybrominated diphenyl ethers (PBDEs) in environmental samples. Versatility of GC-Orbitrap Mass Spectrometry for the Ultra-trace Detection of Persistent Organic Pollutants in Penguin Blood from Antarctica In this study, the performance of the Thermo Scientific™ Q Exactive™ GC Orbitrap™ mass spectrometer was evaluated for routine analysis of POPs within King penguin blood from Antarctica. -
Methods for Long Time Monitoring Using Liquid Electrode Plasma Optical Emission Spectrometry
JAIST Repository https://dspace.jaist.ac.jp/ 液体電極プラズマ発光分光分析法を用いた長期間測定 Title のための方法 Author(s) Ruengpirasiri, Prasongporn Citation Issue Date 2019-09 Type Thesis or Dissertation Text version ETD URL http://hdl.handle.net/10119/16191 Rights Description Supervisor:高村 禅, 先端科学技術研究科, 博士 Japan Advanced Institute of Science and Technology Methods for Long Time Monitoring Using Liquid Electrode Plasma Optical Emission Spectrometry Prasongporn RUENGPIRASIRI Japan Advanced Institute of Science and Technology Doctoral Dissertation Methods for Long Time Monitoring Using Liquid Electrode Plasma Optical Emission Spectrometry Prasongporn RUENGPIRASIRI Supervisor: Professor Yuzuru Takamura Graduate School of Advanced Science and Technology Japan Advanced Institute of Science and Technology Materials Science September 2019 ABstract Liquid electrode plasma (LEP) driven by alternating current (AC) is used as an excitation source for elemental analysis. LEP forms in a vapor bubble generated inside a narrow-center microchannel by using high-voltage power. This technique can detect metals with high sensitivity and high selectivity. More recently, we found the better conditions to generate LEP by alternating current with higher stability and significantly low damages on microchannel, called the new method as AC-LEP. In this plasma, an air bubble remained in the LEP channel during plasma generation by AC power source. The bubble is expected to affect plasma generation strongly. In order to investigate in detail the effect of the bubbles, we fabricated a microfluidic system to introduce different kinds of gas bubbles intentionally into the LEP channel. In AC-LEP, significantly less channel damage (1/3000) was reported compared to direct current LEP (DC-LEP). However, the mechanism has not been clear. -
Thermospray Mass Spectrometry , a New Technique for Studying The
430 Notizen Thermospray Mass Spectrometry , a New charged droplets. These droplets decompose in a Technique for Studying the Relative Stability heated jet chamber in which a pressure of several of Cluster Ions of Salts mbar is maintained, and desolvated ions enter the mass analyser via a small orifice. Typically quadru- G. Schmelzeisen-Redeker, S. S. Wong, pole mass filters are employed. For the production U. Giessmann, and F. W. Röllgen of salt cluster ions the temperatures of the jet and in Institut für Physikalische Chemie der Universität Bonn the jet chamber must be high enough to allow the Z. Naturforsch. 40a,430-431 (1985); decomposition of charged small solid particles. For received February 23. 1985 the ammonium halide this condition is easily achieved. Thermospray (TSP) mass spectrometry provides a means of studying stability effects in the frequency distribution of The ammonium chloride cluster ion distribution cluster ions of salts under conditions of heat transfer to the as obtained by the new TSP technique is shown in cluster ions via thermal collisions in a gas. This is demon- strated for the cluster ions of ammonium chloride. The Figure 2. The TSP mass spectrum was obtained TSP mass spectrum is compared with that obtained by with the experimental arrangement described in sputtering of the salt in secondary ion mass spectrometry. [16], A quadrupole mass filter with a mass range 1-420 was utilized. A 0.1 molar aqueous solution of NH C1 was applied. The temperature at the end Cluster ions of salts are easily generated by 4 of the capillary was 250 °C and the temperature of particle impact in secondary ion mass spectrometry the jet chamber was 180 °C.