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Pangerl J, Sukul P, Rück T, Fuchs P, Weigl S, Miekisch W, Bierl R, Matysik FM. An inexpensive UV-LED photoacoustic based real-time sensor-system detecting exhaled trace-acetone. Photoacoustics 2024; 38:100604. [PMID: 38559568 PMCID: PMC10973644 DOI: 10.1016/j.pacs.2024.100604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/08/2024] [Accepted: 03/20/2024] [Indexed: 04/04/2024]
Abstract
In this research we present a low-cost system for breath acetone analysis based on UV-LED photoacoustic spectroscopy. We considered the end-tidal phase of exhalation, which represents the systemic concentrations of volatile organic compounds (VOCs) - providing clinically relevant information about the human health. This is achieved via the development of a CO2-triggered breath sampling system, which collected alveolar breath over several minutes in sterile and inert containers. A real-time mass spectrometer is coupled to serve as a reference device for calibration measurements and subsequent breath analysis. The new sensor system provided a 3σ detection limit of 8.3 ppbV and an NNEA of 1.4E-9 Wcm-1Hz-0.5. In terms of the performed breath analysis measurements, 12 out of 13 fell within the error margin of the photoacoustic measurement system, demonstrating the reliability of the measurements in the field.
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Affiliation(s)
- Jonas Pangerl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, Regensburg 93053, Germany
- Institute of Analytical Chemistry, Chemo- and Biosensing, University of Regensburg, Regensburg 93053, Germany
| | - Pritam Sukul
- Rostock Medical Breath Analytics and Technologies (RoMBAT), Dept. of Anaesthesiology, Intensive Care Medicine and Pain Therapy, University Medicine Rostock, Rostock 18057, Germany
| | - Thomas Rück
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, Regensburg 93053, Germany
| | - Patricia Fuchs
- Rostock Medical Breath Analytics and Technologies (RoMBAT), Dept. of Anaesthesiology, Intensive Care Medicine and Pain Therapy, University Medicine Rostock, Rostock 18057, Germany
| | - Stefan Weigl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, Regensburg 93053, Germany
| | - Wolfram Miekisch
- Rostock Medical Breath Analytics and Technologies (RoMBAT), Dept. of Anaesthesiology, Intensive Care Medicine and Pain Therapy, University Medicine Rostock, Rostock 18057, Germany
| | - Rudolf Bierl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, Regensburg 93053, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensing, University of Regensburg, Regensburg 93053, Germany
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2
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Pangerl J, Moser E, Müller M, Weigl S, Jobst S, Rück T, Bierl R, Matysik FM. A sub-ppbv-level Acetone and Ethanol Quantum Cascade Laser Based Photoacoustic Sensor - Characterization and Multi-Component Spectra Recording in Synthetic Breath. Photoacoustics 2023; 30:100473. [PMID: 36970564 PMCID: PMC10033733 DOI: 10.1016/j.pacs.2023.100473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 02/24/2023] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
Trace gas analysis in breath is challenging due to the vast number of different components. We present a highly sensitive quantum cascade laser based photoacoustic setup for breath analysis. Scanning the range between 8263 and 8270 nm with a spectral resolution of 48 pm, we are able to quantify acetone and ethanol within a typical breath matrix containing water and CO2. We photoacoustically acquired spectra within this region of mid-infra-red light and prove that those spectra do not suffer from non-spectral interferences. The purely additive behavior of a breath sample spectrum was verified by comparing it with the independently acquired single component spectra using Pearson and Spearman correlation coefficients. A previously presented simulation approach is improved and an error attribution study is presented. With a 3σ detection limit of 6.5 ppbv in terms of ethanol and 250 pptv regarding acetone, our system is among the best performing presented so far.
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Affiliation(s)
- Jonas Pangerl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Elisabeth Moser
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
- Faculty of Informatics, Technical University of Munich, 85748 Garching, Germany
| | - Max Müller
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Stefan Weigl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
| | - Simon Jobst
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Thomas Rück
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
| | - Rudolf Bierl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
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Böhm D, Koall M, Matysik FM. Combining amperometry and mass spectrometry as a dual detection approach for capillary electrophoresis. Electrophoresis 2023; 44:492-500. [PMID: 36413610 DOI: 10.1002/elps.202200228] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/30/2022] [Accepted: 11/11/2022] [Indexed: 11/23/2022]
Abstract
Dual detection concepts (DDCs) are becoming more and more popular in analytical chemistry. In this work, we describe a novel DDC for capillary electrophoresis (CE) consisting of an amperometric detector (AD) and a mass spectrometer (MS). This detector combination has a good complementarity as the AD exhibits high sensitivity, whereas the MS provides excellent selectivity. Both detectors are based on a destructive detection principle, making a serial detector arrangement impossible. Thus, for the realization of the DDC, the CE flow was divided into two parts with a flow splitter. The DDC was characterized in a proof-of-concept study with ferrocene derivates and a nonaqueous background electrolyte. We could show that splitting the CE flow was a suitable method for the instrumental realization of the DDC consisting of two destructive detectors. By lowering the height of the AD compared to the MS, it was possible to synchronize the detector responses. Additionally, for the chosen model system, we confirmed that the AD was much more reproducible and had lower limits of detection (LODs) than the MS. The LODs were identical for the DDC and the single-detection arrangements, indicating no sensitivity decrease due to the CE flow splitting. The DDC was successfully applied to determine the drug and doping agent trimetazidine.
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Affiliation(s)
- Daniel Böhm
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, Regensburg, Germany
| | - Martin Koall
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, Regensburg, Germany
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4
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Hájková-Strejcová A, Augustín M, Barek J, Iffelsberger C, Matysik FM, Vyskočil V. New strategy in electrochemical investigation of DNA damage demonstrated on genotoxic derivatives of fluorene. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Müller M, Rück T, Jobst S, Pangerl J, Weigl S, Bierl R, Matysik FM. An Algorithmic Approach to Compute the Effect of Non-Radiative Relaxation Processes in Photoacoustic Spectroscopy. Photoacoustics 2022; 26:100371. [PMID: 37614667 PMCID: PMC10442890 DOI: 10.1016/j.pacs.2022.100371] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/22/2022] [Accepted: 05/09/2022] [Indexed: 08/25/2023]
Abstract
Successful transfer of photoacoustic gas sensors from laboratory to real-life applications requires knowledge about potential cross-sensitivities towards environmental and gas matrix changes. Multi-dimensional calibration in case of cross-sensitivities can become very complex or even unfeasible. To address this challenge, we present a novel algorithm to compute the collision based non-radiative efficiency and phase lag of energy relaxation on a molecular level (CoNRad) for photoacoustic signal calculation. This algorithmic approach allows to calculate the entire relaxation cascade of arbitrarily complex systems, yielding a theoretical photoacoustic signal. In this work the influence of varying bulk compositions, i.e. nitrogen (N2), oxygen (O2) and water (H2O) on the photoacoustic signal during methane (CH4) detection is demonstrated. The applicability of the algorithm to other photoacoustic setups is shown exemplary by applying it to the relaxational system investigated in [1]. Hayden et al. examined the effect of water on photoacoustic carbon monoxide (CO) detection.
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Affiliation(s)
- Max Müller
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Thomas Rück
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
| | - Simon Jobst
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Jonas Pangerl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Stefan Weigl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
| | - Rudolf Bierl
- Sensorik-ApplikationsZentrum (SappZ), Regensburg University of Applied Sciences, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo, and Biosensors, University of Regensburg, 93053 Regensburg, Germany
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Iffelsberger C, Wert S, Matysik FM, Pumera M. Catalyst Formation and In Operando Monitoring of the Electrocatalytic Activity in Flow Reactors. ACS Appl Mater Interfaces 2021; 13:35777-35784. [PMID: 34283572 DOI: 10.1021/acsami.1c09127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Flow reactors are of increasing importance and have become crucial devices due to their wide application in chemical synthesis, electrochemical hydrogen evolution reaction (HER), or electrochemical waste water treatment. In many of these applications, catalyst materials such as transition-metal chalcogenides (TMCs) for the HER, provide the desired electrochemical reactivity for the HER. Generally, the flow electrolyzers' performance is evaluated as the overall output, but the decrease in activity of the electrolyzer is due to localized failure of the catalyst. Herein, we present a method for the spatially resolved (tens of micrometers) In Operando analysis of the catalytic activity under real operation conditions as well as the localized deposition of the catalyst in an operating model flow reactor. For these purposes, scanning electrochemical microscopy was applied for MoSx catalyst deposition and for localized tracking of the TMC activity with a resolution of 25 μm. This approach offers detailed information about the catalytic performance and should find broad application for the characterization and optimization of flow reactor catalysis under real operational conditions.
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Affiliation(s)
- Christian Iffelsberger
- Future Energy and Innovation Laboratory, Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
| | - Stefan Wert
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Martin Pumera
- Future Energy and Innovation Laboratory, Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
- Department of Food Technology, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
- Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
- Department of Medical Research, China Medical University Hospital, China Medical University, No. 91 Hsueh-Shih Road, Taichung 40402, Taiwan
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7
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Raith T, Kröninger A, Mickert MJ, Gorris HH, Matysik FM. Enhanced resolution of generator-collector studies of enzymatic structures by means of hydrodynamic scanning electrochemical microscopy. Talanta 2020; 214:120844. [PMID: 32278425 DOI: 10.1016/j.talanta.2020.120844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 11/19/2022]
Abstract
In this report, the effects of forced convection on scanning electrochemical microscopy (SECM) studies of enzymes in the context of the generator-collector mode (G/C mode) were investigated. Forced convection was generated via an electrical high precision stirrer integrated into the electrochemical cell. Circular spots of glucose oxidase were immobilized on a gold support serving as model substrate. The diffusion layer of enzymatically generated H2O2 was characterized recording probe scan curves (PSCs) in z-direction. Furthermore, the enzyme-modified surfaces were investigated via constant-height SECM imaging in feedback mode and in G/C mode. For methodical comparison all sets of experiments were performed in quiescent solution (conventional approach) and with forced convection, respectively. In contrast to a growing diffusion layer without forced convection by applying forced convection, a constant diffusion layer of produced H2O2 was observed. Hence, via hydrodynamic SECM time-independent images within a reasonable time scale of SECM measurements in G/C mode were enabled and their resolution was enhanced.
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Affiliation(s)
- Timo Raith
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053, Regensburg, Germany
| | - Anna Kröninger
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053, Regensburg, Germany
| | - Matthias J Mickert
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053, Regensburg, Germany
| | - Hans H Gorris
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053, Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053, Regensburg, Germany.
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Herl T, Matysik FM. Investigation of the Electrooxidation of Thymine on Screen-Printed Carbon Electrodes by Hyphenation of Electrochemistry and Mass Spectrometry. Anal Chem 2020; 92:6374-6381. [PMID: 32227929 DOI: 10.1021/acs.analchem.9b05406] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The electrooxidation of thymine on screen-printed carbon electrodes was investigated utilizing different complementary instrumental approaches. The potential-dependent product profile was obtained by recording real-time mass voltammograms. Electrochemical flow cells with integrated disposable electrodes were directly coupled with mass spectrometry to facilitate a very fast detection of electrogenerated species. Thymine dimers were found at a potential of about 1.1 V in ammonium acetate (pH 7.0) and 1.25 V in ammonium hydrogen carbonate electrolyte (pH 8.0). Electrochemistry-capillary electrophoresis-mass spectrometry measurements revealed that two isobaric isomers of a dimeric oxidation product were formed. Separations at different time intervals between end of oxidation and start of separation showed that these were hydrated over time. An investigation of the pKa values by changing the separation conditions in electrochemistry-capillary electrophoresis-ultraviolet-visible spectroscopy measurements allowed for further characterization of the primary oxidation products. The results showed that both isomers exhibited two deprotonation steps. The oxidation products were further characterized by high-performance liquid chromatography-tandem mass spectrometry. Based on the obtained data, the main oxidation products of thymine in aqueous solution could most likely be identified as N(1)-C(5') and N(1)-C(6') linked dimer species evolving into the corresponding dimer hydrates over time. The presented methods for online characterization of electrochemically pretreated samples showed that not only mass spectrometric data can be obtained by electrochemistry-mass spectrometry but also further characterizations such as the investigation of product stability and the pH-dependent protonation or deprotonation behavior are possible. This is valid not only for stable oxidation products but also for intermediates, as analysis can be carried out within a short time scale. Thus, a vast amount of valuable experimental data can be acquired, which can help in understanding electrooxidation processes.
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Affiliation(s)
- Thomas Herl
- Faculty of Chemistry and Pharmacy, Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Faculty of Chemistry and Pharmacy, Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
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Müller A, Sachse S, Decker M, Matysik FM, Vonau W. Comparison of H2O2 screen-printed sensors with different Prussian blue nanoparticles as electrode material. J Electrochem Sci Eng 2020. [DOI: 10.5599/jese.719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In order to determine hydrogen peroxide condensing from gaseous and liquid phases screen-printed electrodes with controlled and adjustable thickness, shape and size of the working electrode as well as electrode paste composition were investigated. For this purpose Prussian blue (PB) nanoparticles with a different particle size distribution of 20-30 nm (synthesized) and 60-100 nm (commercially available) were mixed with carbon paste and screen-printed on Al2O3 templates to establish H2O2-sensitive electrode. These two types of screen-printed sensors were compared to the commercial one during measurements in H2O2/water solutions at concentrations between 10-5 and 10-2 M H2O2. The linear signal in the investigated concentration range was found only for the sensor with the commercially available PB particles. Thus, this sensor prepared with PB particles of the size 60-100 nm showed the most reproducible and time-stable response versus the analyte in comparison to the others. This result offers the possibility to create sensors with adjustable design adapted to the concrete functionality. Thin films of collecting electrolytes based on agarose gels were printed on the sensor structures. They showed a distinct response on the application of H2O2-containing aerosols and gaseous phase.
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10
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Wert S, Fußstetter A, Iffelsberger C, Matysik FM. Scanning Electrochemical Microscopy of Electrically Heated Wire Substrates. Molecules 2020; 25:molecules25051169. [PMID: 32150947 PMCID: PMC7179101 DOI: 10.3390/molecules25051169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 02/24/2020] [Accepted: 02/29/2020] [Indexed: 11/16/2022] Open
Abstract
We report a new configuration for enhancing the performance of scanning electrochemical microscopy (SECM) via heating of the substrate electrode. A flattened Pt microwire was employed as the substrate electrode. The substrate was heated by an alternating current (AC), resulting in an increased mass transfer between the wire surface and the bulk solution. The electrochemical response of the Pt wire during heating was investigated by means of cyclic voltammetry (CV). The open circuit potential (OCP) of the wire was recorded over time, while varied heating currents were applied to investigate the time needed for establishing steady-state conditions. Diffusion layer studies were carried out by performing probe approach curves (PACs) for various measuring modes of SECM. Finally, imaging studies of a heated substrate electrode surface, applying feedback, substrate generation/tip collection (SG/TC), and the competition mode of SECM, were performed and compared with room temperature results.
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Affiliation(s)
- Stefan Wert
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstr. 31, 93053 Regensburg, Germany; (S.W.); (A.F.)
| | - Alexander Fußstetter
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstr. 31, 93053 Regensburg, Germany; (S.W.); (A.F.)
| | - Christian Iffelsberger
- Future Energy and Innovations Laboratory, CEITEC—Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czech Republic;
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstr. 31, 93053 Regensburg, Germany; (S.W.); (A.F.)
- Correspondence: ; Tel.: +49-941-943-4547
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Durner B, Ehmann T, Matysik FM. Separation of linear and cyclic poly(dimethylsiloxanes) with polymer high-performance liquid chromatography. Monatsh Chem 2019. [DOI: 10.1007/s00706-019-02389-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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12
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Hanekamp P, Raith T, Iffelsberger C, Zankl T, Robl W, Matysik FM. Material contrast studies of conductive thin films on semiconductor substrates using scanning electrochemical microscopy. J APPL ELECTROCHEM 2019. [DOI: 10.1007/s10800-019-01294-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Durner B, Ehmann T, Matysik FM. High-resolution polymer high performance liquid chromatography: Application of a saw tooth gradient for the separation of various polymers. J Chromatogr A 2019; 1587:88-100. [DOI: 10.1016/j.chroma.2018.11.075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/20/2018] [Accepted: 11/28/2018] [Indexed: 11/27/2022]
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Beutner A, Herl T, Matysik FM. Selectivity enhancement in capillary electrophoresis by means of two-dimensional separation or dual detection concepts. Anal Chim Acta 2018; 1057:18-35. [PMID: 30832915 DOI: 10.1016/j.aca.2018.11.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 11/01/2018] [Accepted: 11/19/2018] [Indexed: 12/18/2022]
Abstract
For the identification and quantification of analytes in complex samples, highly selective analytical strategies are required. The selectivity of single separation techniques such as gas chromatography (GC), liquid chromatography (LC), or capillary electrophoresis (CE) with common detection principles can be enhanced by hyphenating orthogonal separation techniques but also by using complementary detection systems. In this review, two-dimensional systems containing CE in at least one dimension are reviewed, namely LC-CE or 2D CE systems. Particular attention is paid to the aspect of selectivity enhancement due to the orthogonality of the different separation mechanisms. As an alternative concept, dual detection approaches are reviewed using the common detectors of CE such as UV/VIS, laser-induced fluorescence, capacitively coupled contactless conductivity (C4D), electrochemical detection, and mass spectrometry. Special emphasis is given to dual detection systems implementing the highly flexible C4D as one detection component. Selectivity enhancement can be achieved in case of complementarity of the different detection techniques.
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Affiliation(s)
- Andrea Beutner
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053, Regensburg, Germany
| | - Thomas Herl
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053, Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053, Regensburg, Germany.
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Němečková-Makrlíková A, Matysik FM, Navrátil T, Barek J, Vyskočil V. Determination of three Tumor Biomarkers (Homovanillic Acid, Vanillylmandelic Acid, and 5-Hydroxyindole-3-Acetic Acid) Using Flow Injection Analysis with Amperometric Detection. ELECTROANAL 2018. [DOI: 10.1002/elan.201800540] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Anna Němečková-Makrlíková
- Charles University, Faculty of Science, Department of Analytical Chemistry; UNESCO Laboratory of Environmental Electrochemistry; Hlavova 2030/8, CZ- 128 43 Prague 2 Czech Republic
- J. Heyrovský Institute of Physical Chemistry of the AS CR, v.v.i.; Dolejškova 2155/3 CZ-182 23 Prague 8 Czech Republic
| | - Frank-Michael Matysik
- University of Regensburg; Institute of Analytical Chemistry, Chemo- and Biosensors; Universitätsstraße 31 D-93053 Regensburg Germany
| | - Tomáš Navrátil
- J. Heyrovský Institute of Physical Chemistry of the AS CR, v.v.i.; Dolejškova 2155/3 CZ-182 23 Prague 8 Czech Republic
| | - Jiří Barek
- Charles University, Faculty of Science, Department of Analytical Chemistry; UNESCO Laboratory of Environmental Electrochemistry; Hlavova 2030/8, CZ- 128 43 Prague 2 Czech Republic
| | - Vlastimil Vyskočil
- Charles University, Faculty of Science, Department of Analytical Chemistry; UNESCO Laboratory of Environmental Electrochemistry; Hlavova 2030/8, CZ- 128 43 Prague 2 Czech Republic
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16
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Raith T, Iffelsberger C, Vatsyayan P, Matysik FM. Impacts of Forced Convection Generated via High Precision Stirring on Scanning Electrochemical Microscopy Experiments in Feedback Mode. ELECTROANAL 2018. [DOI: 10.1002/elan.201800562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Timo Raith
- Institute of Analytical Chemistry, Chemo- and Biosensors; University of Regensburg; 93053 Regensburg Germany
| | - Christian Iffelsberger
- Institute of Analytical Chemistry, Chemo- and Biosensors; University of Regensburg; 93053 Regensburg Germany
| | - Preety Vatsyayan
- Institute of Analytical Chemistry, Chemo- and Biosensors; University of Regensburg; 93053 Regensburg Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors; University of Regensburg; 93053 Regensburg Germany
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Trindade MAG, Martins CA, Angnes L, Herl T, Raith T, Matysik FM. New Electrochemical Flow-Cell Configuration Integrated into a Three-Dimensional Microfluidic Platform: Improving Analytical Application in the Presence of Air Bubbles. Anal Chem 2018; 90:10917-10926. [PMID: 30125484 DOI: 10.1021/acs.analchem.8b02438] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A newly configured electrochemical flow cell to be used for (end-channel) amperometric detection in a microfluidic device is presented. The design was assembled to place the reference electrode in a separated compartment, isolated from the flow in the microchannel, while the working and counter electrodes remain in direct contact with both compartments. Moreover, a three-dimensional coil-shaped microfluidic device was fabricated using a nonconventional protocol. Both devices working in association enabled us to solve the drawback caused by the discrete injection when the automatic micropipette was used. The high performance of the proposed electrochemical flow cell was demonstrated after in situ modifying the surface of the platinum working electrode with surfactant (e.g., using Tween 20 at 0.10%). As the reference electrode remained out of contact with the flowing solution, there was no trouble by air bubble formation (generated by accidental insertion or by presence of surfactants) throughout the measurements. This device was characterized regarding its analytical performance by evaluating the amperometric detection of acetaminophen, enabling determination from 6.60 to 66.0 μmol L-1. This issue is important since at high concentration (e.g., as assessed in clinical analysis) the acetaminophen is known to passivate the working electrode surfaces by electrogenerated products, impairing the accuracy of the electrochemical measurements.
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Affiliation(s)
- Magno Aparecido Gonçalves Trindade
- Faculdade de Ciências Exatas e Tecnologia , Universidade Federal da Grande Dourados , Rodovia Dourados-Itahum, km 12 , 79804-970 Dourados , Mato Grosso do Sul , Brazil.,National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactives , Institute of Chemistry, Universidade Estadual Paulista , P.O. Box 355 , 14800-900 Araraquara , São Paulo , Brazil.,Institute of Analytical Chemistry, Chemo- and Biosensors , University of Regensburg , Universitätsstrasse 31 , DE-93053 Regensburg , Germany
| | - Cauê Alves Martins
- Faculdade de Ciências Exatas e Tecnologia , Universidade Federal da Grande Dourados , Rodovia Dourados-Itahum, km 12 , 79804-970 Dourados , Mato Grosso do Sul , Brazil
| | - Lucio Angnes
- Departamento de Química Fundamental , Instituto de Química, Universidade de São Paulo , Avenida Professor Lineu Prestes, 748 , CEP 05508-000 São Paulo , São Paulo , Brazil
| | - Thomas Herl
- Institute of Analytical Chemistry, Chemo- and Biosensors , University of Regensburg , Universitätsstrasse 31 , DE-93053 Regensburg , Germany
| | - Timo Raith
- Institute of Analytical Chemistry, Chemo- and Biosensors , University of Regensburg , Universitätsstrasse 31 , DE-93053 Regensburg , Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors , University of Regensburg , Universitätsstrasse 31 , DE-93053 Regensburg , Germany
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18
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Iffelsberger C, Raith T, Vatsyayan P, Vyskočil V, Matysik FM. Detection and imaging of reactive oxygen species associated with the electrochemical oxygen evolution by hydrodynamic scanning electrochemical microscopy. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.05.115] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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19
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Durner B, Ehmann T, Matysik FM. Adaption of a parallel-path poly(tetrafluoroethylene) nebulizer to an evaporative light scattering detector: Optimization and application to studies of poly(dimethylsiloxane) oligomers as a model polymer. J Chromatogr A 2018; 1564:214-223. [DOI: 10.1016/j.chroma.2018.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 05/27/2018] [Accepted: 06/04/2018] [Indexed: 10/14/2022]
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20
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Beutner A, Piendl SK, Wert S, Matysik FM. Methodical studies of the simultaneous determination of anions and cations by IC×CE–MS using arsenic species as model analytes. Anal Bioanal Chem 2018; 410:6321-6330. [DOI: 10.1007/s00216-018-1241-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 06/11/2018] [Accepted: 07/02/2018] [Indexed: 01/01/2023]
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21
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Braun P, Gebhard J, Matysik FM, Rabl HP. Potential Technical Approaches for Improving Low-Temperature NOxConversion of Exhaust Aftertreatment Systems. CHEM-ING-TECH 2018. [DOI: 10.1002/cite.201700122] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Peter Braun
- Ostbayerische Technische Hochschule Regensburg; Fakultät Maschinenbau; Galgenbergstraße 30 93053 Regensburg Germany
- Universität Regensburg; Institute of Analytical Chemistry, Chemo- and Biosensors; Universitätsstraße 31 93053 Regensburg Germany
| | - Jürgen Gebhard
- Ostbayerische Technische Hochschule Regensburg; Fakultät Maschinenbau; Galgenbergstraße 30 93053 Regensburg Germany
| | - Frank-Michael Matysik
- Universität Regensburg; Institute of Analytical Chemistry, Chemo- and Biosensors; Universitätsstraße 31 93053 Regensburg Germany
| | - Hans-Peter Rabl
- Ostbayerische Technische Hochschule Regensburg; Fakultät Maschinenbau; Galgenbergstraße 30 93053 Regensburg Germany
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22
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Beutner A, Scherer B, Matysik FM. Dual detection for non-aqueous capillary electrophoresis combining contactless conductivity detection and mass spectrometry. Talanta 2018; 183:33-38. [PMID: 29567184 DOI: 10.1016/j.talanta.2018.02.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 02/01/2018] [Accepted: 02/04/2018] [Indexed: 11/28/2022]
Abstract
Coupling of two detectors is a powerful tool to enhance the overall analytical performance generating complementary information and overcoming the limitations of the single detectors. In this work, capacitively coupled contactless conductivity detection (C4D) and electrospray ionization mass spectrometry (ESI-MS) were coupled in conjunction with non-aqueous capillary electrophoresis (NACE). Non-aqueous electrolytes are highly compatible with ESI due to their volatility. Moreover, they exhibit low background conductivity, which is essential for the detection with C4D. A NACE-C4D-MS method was developed using an acetonitrile buffer containing 2 M HAc and 4 mM NH4Ac as background electrolyte. The influence of the inner diameter of the separation capillary on the C4D was studied and taken into account. A capillary with 50 µm inner diameter was found to be best suited. The complementarity of the two detectors was shown by determining a sample mixture containing choline, thiamine, nitrate, and chloride as well as bromide and acetylcholine as internal standards. The C4D was the detector of choice for the inorganic ions, which were not detectable with the MS whereas the MS had much lower limits of detections for the organic biomolecules. The method was applied on an extract of a food supplement containing the model analytes.
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Affiliation(s)
- Andrea Beutner
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany
| | - Beate Scherer
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany.
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23
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Klouda J, Barek J, Kočovský P, Herl T, Matysik FM, Nesměrák K, Schwarzová-Pecková K. Bile acids: Electrochemical oxidation on bare electrodes after acid-induced dehydration. Electrochem commun 2018. [DOI: 10.1016/j.elecom.2017.11.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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24
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Hanekamp P, Robl W, Matysik FM. Development and application of a multipurpose electrodeposition cell configuration for studying plating processes on wafer specimen and for characterizing surface films by scanning electrochemical microscopy. J APPL ELECTROCHEM 2017. [DOI: 10.1007/s10800-017-1124-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Iffelsberger C, Vatsyayan P, Matysik FM. Scanning Electrochemical Microscopy with Forced Convection Introduced by High-Precision Stirring. Anal Chem 2017; 89:1658-1664. [DOI: 10.1021/acs.analchem.6b03764] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christian Iffelsberger
- Institute of Analytical Chemistry,
Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Preety Vatsyayan
- Institute of Analytical Chemistry,
Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry,
Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany
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Mohorič U, Beutner A, Krickl S, Touraud D, Kunz W, Matysik FM. Surfactant-free microemulsion electrokinetic chromatography (SF-MEEKC) with UV and MS detection - a novel approach for the separation and ESI-MS detection of neutral compounds. Anal Bioanal Chem 2016; 408:8681-8689. [PMID: 27866256 DOI: 10.1007/s00216-016-0057-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 10/14/2016] [Accepted: 10/24/2016] [Indexed: 11/25/2022]
Abstract
Microemulsion electrokinetic chromatography (MEEKC) is a powerful tool to separate neutral species based on differences in their hydrophobic and hydrophilic properties. However, as a major drawback the conventionally used SDS based microemulsions are not compatible with electrospray ionization mass spectrometry (ESI-MS). In this work, a surfactant-free microemulsion (SFME) consisting of water, ethanol, and 1-octanol is used for surfactant-free microemulsion electrokinetic chromatography (SF-MEEKC). Ammonium acetate was added to the SFME enabling electrophoretic separations. The stability of SFMEs containing ammonium acetate was investigated using small-angle X-ray scattering and dynamic light scattering. A method for the separation of a model system of hydrophobic and hydrophilic neutral vitamins, namely the vitamins B2 and D3, and the cationic vitamin B1 was developed using UV/VIS detection. The influence of the ammonium acetate concentration on the separation performance was studied in detail. The method was characterized concerning reproducibility of migration times and peak areas and concerning the linearity of the calibration data. Furthermore, SF-MEEKC was coupled to ESI-MS investigating the compatibility between SFMEs and the ESI process. The signal intensities of ESI-MS measurements of the model analytes were comparable for SFMEs and aqueous systems. Finally, the vitamin D3 content of a drug treating vitamin D3 deficiency was determined by SF-MEEKC coupled to ESI-MS using 25-hydroxycholecalciferol as an internal standard. Graphical abstract The concept of surfactant-free microemulsion electrokinetic chromatography coupled to electrospray ionization mass spectrometry.
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Affiliation(s)
- Urška Mohorič
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Andrea Beutner
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Sebastian Krickl
- Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Didier Touraud
- Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Werner Kunz
- Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053, Regensburg, Germany.
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27
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Viehbeck S, Matysik FM. Application of direct analysis in real time (DART) and direct inlet probe (DIP-APCI) mass spectrometry in the context of industrial sample analysis. Monatsh Chem 2016. [DOI: 10.1007/s00706-016-1789-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Laube H, Matysik FM, Schmidberger A, Mehlmann K, Toursel A, Boden J. CE-UV/VIS and CE-MS for monitoring organic impurities during the downstream processing of fermentative-produced lactic acid from second-generation renewable feedstocks. J Biol Eng 2016; 10:7. [PMID: 27200108 PMCID: PMC4872333 DOI: 10.1186/s13036-016-0027-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 04/03/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND During the downstream process of bio-based bulk chemicals, organic impurities, mostly residues from the fermentation process, must be separated to obtain a pure and ready-to-market chemical. In this study, capillary electrophoresis was investigated for the non-targeting downstream process monitoring of organic impurities and simultaneous quantitative detection of lactic acid during the purification process of fermentatively produced lactic acid. The downstream process incorporated 11 separation units, ranging from filtration, adsorption and ion exchange to electrodialysis and distillation, and 15 different second-generation renewable feedstocks were processed into lactic acid. The identification of organic impurities was established through spiking and the utilization of an advanced capillary electrophoresis mass spectrometry system. RESULTS A total of 53 % of the organic impurities were efficiently removed via bipolar electrodialysis; however, one impurity, pyroglutamic acid, was recalcitrant to separation. It was demonstrated that the presence of pyroglutamic acid disrupts the polymerization of lactic acid into poly lactic acid. Pyroglutamic acid was present in all lactic acid solutions, independent of the type of renewable resource or the bacterium applied. Pyroglutamic acid, also known as 5-oxoproline, is a metabolite in the glutathione cycle, which is present in all living microorganisms. pyroglutamic acid is found in many proteins, and during intracellular protein metabolism, N-terminal glutamic acid and glutamine residues can spontaneously cyclize to become pyroglutamic acid. Hence, the concentration of pyroglutamic acid in the lactic acid solution can only be limited to a certain amount. CONCLUSIONS The present study proved the capillary electrophoresis system to be an important tool for downstream process monitoring. The high product concentration encountered in biological production processes did not hinder the capillary electrophoresis from separating and detecting organic impurities, even at minor concentrations. The coupling of the capillary electrophoresis with a mass spectrometry system allowed for the straightforward identification of the remaining critical impurity, pyroglutamic acid. Although 11 separation units were applied during the downstream process, the pyroglutamic acid concentration remained at 12,900 ppm, which was comparatively high. All organic impurities found were tracked by the capillary electrophoresis, allowing for further separation optimization.
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Affiliation(s)
- Hendrik Laube
- Department of Bioengineering, Leibniz-Institute for Agricultural Engineering (ATB), Max-Eyth-Allee 100, Potsdam, 14469 Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Regensburg, Germany
| | - Andreas Schmidberger
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Regensburg, Germany
| | - Kerstin Mehlmann
- Department of Bioengineering, Leibniz-Institute for Agricultural Engineering (ATB), Max-Eyth-Allee 100, Potsdam, 14469 Germany
| | - Andreas Toursel
- Department of Bioengineering, Leibniz-Institute for Agricultural Engineering (ATB), Max-Eyth-Allee 100, Potsdam, 14469 Germany
| | - Jana Boden
- ICA Boden-Haumann-Mainka, Engineering Society for Chemical Analysis, Langen, Hessen Germany
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29
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Beutner A, Cunha RR, Richter EM, Matysik FM. Combining C4
D and MS as a dual detection approach for capillary electrophoresis. Electrophoresis 2016; 37:931-5. [DOI: 10.1002/elps.201500512] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 12/23/2015] [Accepted: 12/23/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Andrea Beutner
- Institute for Analytical Chemistry, Chemo- and Biosensors; Regensburg Germany
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30
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Matczuk M, Aleksenko SS, Matysik FM, Jarosz M, Timerbaev AR. Comparison of detection techniques for capillary electrophoresis analysis of gold nanoparticles. Electrophoresis 2015; 36:1158-63. [PMID: 25781270 DOI: 10.1002/elps.201400597] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 03/02/2015] [Accepted: 03/02/2015] [Indexed: 11/08/2022]
Abstract
As metallic nanoparticles are growing in importance as analytes in CE, increases an interest in appropriate detection methods for their quantification in various samples. For gold nanoparticles (AuNPs), the most common UV detection poses intricacy of inadequate sensitivity that hinders the applicability of CE. With the objective of resolving this challenge, UV detection was compared with C(4) D and ICP-MS as alternative modes of detection for AuNPs. A C(4) D detector, applied under pressure-driven conditions, exhibited better sensitivity than a UV detector. However, C(4) D turned to be unsatisfactory to differentiate the signal of AuNPs at common CE conditions despite varying the nature of BGE and detection conditions. Due to intrinsic sensitivity and low background levels typical to Au, ICP-MS greatly surpasses UV detection. After optimization trials, CE-ICP-MS gained the LOD of AuNPs as low as 2 × 10(-15) M, as well as an excellent performance in terms of signal stability and linearity. Also importantly, the optimized BGE appears to be well matched to explore the behavior of AuNPs in biologically relevant systems. This was demonstrated by probing the interaction between AuNPs and the main blood-transporting protein, HSA.
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Affiliation(s)
- Magdalena Matczuk
- Chair of Analytical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Warsaw, Poland
| | - Svetlana S Aleksenko
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Regensburg, Germany
| | - Maciej Jarosz
- Chair of Analytical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Warsaw, Poland
| | - Andrei R Timerbaev
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
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31
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Rothenhöfer M, Grundmann M, Bernhardt G, Matysik FM, Buschauer A. High performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) for the sensitive determination of hyaluronan oligosaccharides. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 988:106-15. [DOI: 10.1016/j.jchromb.2015.02.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 02/18/2015] [Accepted: 02/19/2015] [Indexed: 01/28/2023]
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Beutner A, Kochmann S, Mark JJP, Matysik FM. Two-dimensional separation of ionic species by hyphenation of capillary ion chromatography × capillary electrophoresis-mass spectrometry. Anal Chem 2015; 87:3134-8. [PMID: 25708415 DOI: 10.1021/ac504800d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The separation of complex mixtures such as biological or environmental samples requires high peak capacities, which cannot be established with a single separation technique. Therefore, multidimensional systems are in demand. In this work, we present the hyphenation of the two most important (orthogonal) techniques in ion analysis, namely, ion chromatography (IC) and capillary electrophoresis (CE), in combination with mass spectrometry. A modulator was developed ensuring a well-controlled coupling of IC and CE separations. Proof-of-concept measurements were performed using a model system consisting of nucleotides and cyclic nucleotides. The data are presented in a multidimensional contour plot. Analyte stacking in the CE separation could be exploited on the basis of the fact that the suppressed IC effluent is pure water.
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Affiliation(s)
- Andrea Beutner
- Institute for Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Sven Kochmann
- Institute for Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Jonas Josef Peter Mark
- Institute for Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Institute for Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
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Kochmann S, Matysik FM. Hyphenation of capillary high-performance ion-exchange chromatography with mass spectrometry using sheath-flow electrospray ionization. Rapid Commun Mass Spectrom 2014; 28:2670-2680. [PMID: 25366413 DOI: 10.1002/rcm.7056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 08/08/2014] [Accepted: 09/15/2014] [Indexed: 06/04/2023]
Abstract
RATIONALE Mass spectrometry (MS) is an attractive method for extending capillary-size ion chromatography (cHPIC) to create a valuable technique for speciation analysis. For hyphenation, the aqueous effluent of cHPIC has to be transformed into a volatile mixture for MS while preserving analytical concentrations as well as peak shapes during transfer from cHPIC to MS. Finally, the approach should technically be flexible and easy-to-use. A combination of cHPIC and sheath-flow electrospray ionization (ESI)-MS offers to solve all these challenges. METHODS cHPIC/sheath-flow-ESI-TOFMS was used in this study for the speciation analysis of various arsenic model compounds. These model compounds were analyzed with different hyphenation setups and configurations of cHPIC/MS and their respective assets and drawbacks were examined and discussed. The parameters (flow rate and composition of sheath liquid) of sheath-flow ESI and their influence on the performance of the spray and the sensitivity of the detector were investigated and compared with those of sheathless ESI. RESULTS Using an injection valve to couple cHPIC and MS was found to be the best method for hyphenation, since it constitutes a flexible and dead-volume-free approach. The investigation of sheath-flow ESI revealed that the flow rate of the sheath liquid has to resemble the flow rate of the IC effluent to ensure a stable spray and that a composition of 2-propanol/water/ammonia at 50:50:0.2 (v/v/v) suits most applications without unilaterally promoting the sensitivity for either organic or inorganic compounds. The optimized setup and conditions were successfully applied to the analysis of a mixture of important arsenic species and used to determine limits of detection of organic and inorganic arsenic species (3.7 µg L(-1) elemental arsenic). CONCLUSIONS A method for cHPIC/sheath-flow-ESI-MS was developed. The method was shown to be a valuable tool for speciation and trace analysis. It features no dead volume, fast transfer from IC to MS, only minimal peak-widening, high reproducibility, and the ability to fine-tune the ESI spray for higher sensitivity and stability by adjusting the composition of the sheath-liquid.
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Affiliation(s)
- Sven Kochmann
- Institute of Analytical Chemistry, University of Regensburg, Universitätsstr. 31, D-93053, Regensburg, Germany
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Cindric M, Vojs M, Matysik FM. Characterization of the Oxidative Behavior of Cyclic Nucleotides Using Electrochemistry-Mass Spectrometry. ELECTROANAL 2014. [DOI: 10.1002/elan.201400414] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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35
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Mark JJP, Beutner A, Cindric M, Matysik FM. Microanalytical study of sub-nanoliter samples by capillary electrophoresis – mass spectrometry with 100 % injection efficiency. Mikrochim Acta 2014. [DOI: 10.1007/s00604-014-1339-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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36
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Kling B, Bücherl D, Palatzky P, Matysik FM, Decker M, Wegener J, Heilmann J. Flavonoids, flavonoid metabolites, and phenolic acids inhibit oxidative stress in the neuronal cell line HT-22 monitored by ECIS and MTT assay: a comparative study. J Nat Prod 2014; 77:446-454. [PMID: 24245939 DOI: 10.1021/np400518k] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A real-time and label-free in vitro assay based on electric cell-substrate impedance sensing (ECIS) was established, validated, and compared to an end-point MTT assay within an experimental trial addressing the cytoprotective effects of 19 different flavonoids, flavonoid metabolites, and phenolic acids and their methyl esters on the HT-22 neuronal cell line, after induction of oxidative stress with tert-butyl hydroperoxide. Among the flavonoids under study, only those with a catechol unit and an additional 4-keto group provided cytoprotection. The presence of a 2,3-double bond was not a structural prerequisite for a neuroprotective effect. In the case of the phenolics, catechol substitution was the only structural requirement for activity. The flavonoids and other phenolics with a ferulic acid substitution or a single hydroxy group showed no activity. Electrochemical characterization of all compounds via square-wave voltammetry provided a rather specific correlation between cytoprotective activity and redox potential for the active flavonoids, but not for the active phenolics with a low molecular weight. Moreover this study was used to compare label-free ECIS recordings with results of the established MTT assay. Whereas the former provides time-resolved and thus entirely unbiased information on changes of cell morphology that are unequivocally associated with cell death, the latter requires predefined exposure times and a strict causality between metabolic activity and cell death. However, MTT assays are based on standard lab equipment and provide a more economic way to higher throughput.
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Affiliation(s)
- Beata Kling
- Institut für Pharmazie, Universität Regensburg , Universitätsstraße 31, 93053 Regensburg, Germany
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Zöpfl A, Lemberger MM, König M, Ruhl G, Matysik FM, Hirsch T. Reduced graphene oxide and graphene composite materials for improved gas sensing at low temperature. Faraday Discuss 2014; 173:403-14. [DOI: 10.1039/c4fd00086b] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Reduced graphene oxide (rGO) was investigated as a material for use in chemiresistive gas sensors. The carbon nanomaterial was transferred onto a silicon wafer with interdigital gold electrodes. Spin coating turned out to be the most reliable transfer technique, resulting in consistent rGO layers of reproducible quality. Fast changes in the electrical resistance at a low operating temperature of 85 °C could be detected for the gases NO2, CH4 and H2. Especially upon adsorption of NO2 the high signal changes allowed a minimum detection of 0.3 ppm (S/N = 3). To overcome the poor selectivity, rGO was chemically functionalized with octadecylamine, or modified by doping with metal nanoparticles such as Pd and Pt, and also metal oxides such as MnO2, and TiO2. The different response patterns for six different materials allowed the discrimination of all of the test gases by pattern recognition based on principal component analysis.
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Affiliation(s)
- Alexander Zöpfl
- Institute of Analytical Chemistry, Chemo- and Biosensors
- University of Regensburg
- 93053 Regensburg, Germany
| | | | | | | | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors
- University of Regensburg
- 93053 Regensburg, Germany
| | - Thomas Hirsch
- Institute of Analytical Chemistry, Chemo- and Biosensors
- University of Regensburg
- 93053 Regensburg, Germany
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Malik AK, Grundmann M, Matysik FM. Development of a fast capillary electrophoresis-time-of-flight mass spectrometry method for the speciation of organotin compounds under separation conditions of high electrical field strengths. Talanta 2013; 116:559-62. [DOI: 10.1016/j.talanta.2013.07.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 07/10/2013] [Accepted: 07/11/2013] [Indexed: 11/16/2022]
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Bergner S, Vatsyayan P, Matysik FM. Recent advances in high resolution scanning electrochemical microscopy of living cells--a review. Anal Chim Acta 2013; 775:1-13. [PMID: 23601970 DOI: 10.1016/j.aca.2012.12.042] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 12/14/2012] [Accepted: 12/26/2012] [Indexed: 11/16/2022]
Abstract
This review discusses advances in the field of high resolution scanning electrochemical microscopy (HR-SECM) and scanning ion conductance microscopy (SICM) to study living cells. Relevant references from the advent of this technique in the late 1980s to most recent contributions in 2012 are presented with special discussion on high resolution images. A clear progress especially within the last 5 years can be seen in the field of HR-SECM. Furthermore, we also concentrate on the intrinsic properties of SECM imaging techniques e.g. different modes of image acquisition, their advantages and disadvantages in imaging living cells and strategies for further enhancement of image resolution, etc. Some of the recent advances of SECM in nanoimaging have also been discussed which may have potential applications in high resolution imaging of cellular processes.
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Affiliation(s)
- Stefan Bergner
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany
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Palatzky P, Matysik FM. Development and characterization of a novel semiautomated arrangement for electrochemically assisted injection in combination with capillary electrophoresis time-of-flight mass spectrometry. Electrophoresis 2012; 33:2689-94. [DOI: 10.1002/elps.201200088] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Arroyo-Abad U, Mattusch J, Möder M, Elizalde-González MP, Matysik FM. Identification of degradation products of phenylarsonic acid and o-arsanilic acid in contact with suspensions of soils of volcanic origin. Talanta 2012; 99:310-5. [DOI: 10.1016/j.talanta.2012.05.057] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 05/21/2012] [Accepted: 05/29/2012] [Indexed: 11/24/2022]
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Mark JJP, Scholz R, Matysik FM. Electrochemical methods in conjunction with capillary and microchip electrophoresis. J Chromatogr A 2012; 1267:45-64. [PMID: 22824222 DOI: 10.1016/j.chroma.2012.07.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 07/01/2012] [Accepted: 07/06/2012] [Indexed: 02/06/2023]
Abstract
Electromigrative techniques such as capillary and microchip electrophoresis (CE and MCE) are inherently associated with various electrochemical phenomena. The electrolytic processes occurring in the buffer reservoirs have to be considered for a proper design of miniaturized electrophoretic systems and a suitable selection of buffer composition. In addition, the control of the electroosmotic flow plays a crucial role for the optimization of CE/MCE separations. Electroanalytical methods have significant importance in the field of detection in conjunction with CE/MCE. At present, amperometric detection and contactless conductivity detection are the predominating electrochemical detection methods for CE/MCE. This paper reviews the most recent trends in the field of electrochemical detection coupled to CE/MCE. The emphasis is on methodical developments and new applications that have been published over the past five years. A rather new way for the implementation of electrochemical methods into CE systems is the concept of electrochemically assisted injection which involves the electrochemical conversions of analytes during the injection step. This approach is particularly attractive in hyphenation to mass spectrometry (MS) as it widens the range of CE-MS applications. An overview of recent developments of electrochemically assisted injection coupled to CE is presented.
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Affiliation(s)
- Jonas J P Mark
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Regensburg, Germany
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Bansal P, Gaurav, Nidhi, Malik AK, Matysik FM. Liquid Chromatographic Determination of 1,3,5-Trinitroperhydro-1,3,5-triazine and 2,4,6-Trinitrotoluene in Human Plasma and Groundwater Samples Utilizing Microextraction in Packed Syringe. Chromatographia 2012. [DOI: 10.1007/s10337-012-2262-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
A new method involving pre-concentration on modified silica fiber is described for the speciation of chromium(III) [Cr(III)] and chromium(VI) [Cr(VI)] in aqueous media. This method is based on the different chelating behavior of Cr(III) and Cr(VI) with morpholine-4-carbodithioate (MDTC). Both complexes are extracted on silica fiber modified by sol-gel technology by using 3-aminopropyltriethoxysilane (APS) as a precursor. All extracted samples are directly injected into an high-performance liquid chromatography injector for the simultaneous determination of Cr(III) and Cr(VI). Cr(VI) forms two different complexes, and Cr(III) forms a single complex with MDTC. Therefore, the concentration of Cr(VI) is determined directly from the peak area obtained at 5.4 min; whereas, the assay of Cr(III) is based on subtracting the peak area of Cr(VI) from the total peak area obtained at 4.3 min. Under the optimized conditions, the limits of detection for Cr(III) and Cr(VI) are found to be 0.7 ng/mL and 0.2 ng/mL, respectively.
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Niegel C, Pfeiffer SA, Grundmann M, Arroyo-Abad U, Mattusch J, Matysik FM. Fast separations by capillary electrophoresis hyphenated to electrospray ionization time-of-flight mass spectrometry as a tool for arsenic speciation analysis. Analyst 2012; 137:1956-62. [DOI: 10.1039/c2an15944a] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Grundmann M, Rothenhöfer M, Bernhardt G, Buschauer A, Matysik FM. Fast counter-electroosmotic capillary electrophoresis-time-of-flight mass spectrometry of hyaluronan oligosaccharides. Anal Bioanal Chem 2011; 402:2617-23. [PMID: 21800126 DOI: 10.1007/s00216-011-5254-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 07/10/2011] [Accepted: 07/13/2011] [Indexed: 11/27/2022]
Abstract
Fast capillary electrophoresis-mass spectrometry measurements under counter-electroosmotic analyte migration conditions are presented. Efficient separations of a homologous series of six hyaluronan oligosaccharides (comprising 1-6 hyalobiuronic acid moieties) could be completed in 65 s. Separations were achieved in short-length fused silica capillaries under high electric field strengths of up to 1.25 kV·cm(-1). Capillary inner diameters ranging from 5 to 50 μm were investigated, resulting in an optimal value of 15 μm. The influence of capillary dimensions and buffer composition on separation efficiency and sensitivity are discussed. Optimal separations were achieved using a 28 cm × 15 μm capillary, a separation high voltage of 35 kV, a background electrolyte of 25 mM ammonium acetate adjusted to pH 8.5, and negative ionization mode. The optimized method was successfully applied to a bovine testicular hyaluronidase digest of hyaluronan. Only minimal sample pretreatment for protein-containing samples is required. The simple manual injection procedure and fast separations allow for a sample throughput of 35 samples per hour.
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Affiliation(s)
- Marco Grundmann
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93040 Regensburg, Germany
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Mark JJP, Coufal P, Opekar F, Matysik FM. Comparison of the performance characteristics of two tubular contactless conductivity detectors with different dimensions and application in conjunction with HPLC. Anal Bioanal Chem 2011; 401:1669-76. [PMID: 21761108 DOI: 10.1007/s00216-011-5233-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Revised: 07/01/2011] [Accepted: 07/04/2011] [Indexed: 10/18/2022]
Abstract
Two tubular capacitively coupled contactless conductivity detection (C(4)D) cells with different geometric dimensions were evaluated with regard to their main analytical characteristics under non-separation and separation conditions in conjunction with liquid chromatography. A comparison of the performance of the tubular cells to a previously tested thin-layer detection cell was drawn. Additionally, using a theoretical model the experimental results were compared with sets of calculated values and partially enabled to model the complex behavior of C(4)D detection in combination with high-performance liquid chromatography (HPLC). While cell 1 is characterized by a geometric cell volume of 0.6 μL, a wall thickness of 675 μm, and an inner diameter of 125 μm, the respective values for cell 2 are 2.3 μL, 200 μm, and 250 μm. The main analytical parameters were evaluated using a potassium chloride (KCl) solution. The limits of detection were 0.4 μM KCl (5.7 × 10(-6) S m(-1)) for cell 1 and 0.2 μM KCl (3.2 × 10(-6) S m(-1)) for cell 2, which compares well to the previously found 0.2 μM for the thin-layer cell. A pair of linear ranges was found for both cells in a concentration interval ranging from 1 × 10(-6) to 1 × 10(-4) M (corresponding to 1.5 × 10(-5) to 1.5 × 10(-3) S m(-1)) KCl, respectively. Furthermore, the detector cells were applied to the HPLC separation of a model compound system consisting of benzoic acid, lactic acid, octanesulphonic acid, and sodium capronate. Separation of the compounds was achieved with a Biospher PSI 100 C18 column using 60% aqueous acetonitrile mobile phase. Calibration curves for the examined model system were well correlated (r² > 0.997), and it was found that under separation conditions the arrangement with the lower cell volume (cell 1) yields higher sensitivity and respectively lower limits of detection for all model compounds. Compared with the thin-layer cell, the tubular cells show better overall performance in regard to the determined analytical characteristics.
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Affiliation(s)
- Jonas Josef Peter Mark
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstrasse 31a, 93040 Regensburg, Germany
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Guldan H, Matysik FM, Bocola M, Sterner R, Babinger P. Functional assignment of an enzyme that catalyzes the synthesis of an archaea-type ether lipid in bacteria. Angew Chem Int Ed Engl 2011; 50:8188-91. [PMID: 21761520 DOI: 10.1002/anie.201101832] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 05/19/2011] [Indexed: 11/07/2022]
Abstract
An archaea-type ether lipid in bacteria: PcrB, the bacterial homologue of the archaea-specific geranylgeranylglyceryl phosphate synthase, produces heptaprenylglyceryl phosphate in bacillales. The product becomes dephosphorylated and acetylated in vivo.
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Affiliation(s)
- Harald Guldan
- Institut für Biophysik und physikalische Biochemie, Universität Regensburg, Germany
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Guldan H, Matysik FM, Bocola M, Sterner R, Babinger P. Aufklärung der Funktion eines Enzyms mit der Fähigkeit zur Synthese eines Archaea-typischen Lipids in Bacteria. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201101832] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Kumar A, Burns J, Hoffmann W, Demattio H, Malik AK, Matysik FM. Determination of hydrazines by chip electrophoresis with contactless conductivity detection. Electrophoresis 2011; 32:920-5. [DOI: 10.1002/elps.201000417] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2010] [Revised: 09/06/2010] [Accepted: 09/08/2010] [Indexed: 11/10/2022]
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