Article
Electrochemistry
Shinji Okazaki, Kazuyuki Yoshida, Natsumi Kodera, Shuntaroh Ujiie, Yukino Nishimatsu, Yoshito Tanaka, Tomoo Gomei, Makoto Yamada, Shohei Sakuraba, Tomoki Masuko
Summary: The study evaluated a simple potentiometric sensor composed of two dissimilar metal electrodes for quantitative monitoring of free chlorine concentration in tap water. The sensor showed large signal and good reproducibility at a free chlorine concentration of 0.6 mg/l, with minimal baseline drift and immunity to various environmental factors except for pH.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Chemistry, Analytical
Robert G. Hjort, Raquel R. A. Soares, Jingzhe Li, Dapeng Jing, Lindsey Hartfiel, Bolin Chen, Bryan Van Belle, Michelle Soupir, Emily Smith, Eric McLamore, Jonathan C. Claussen, Carmen L. Gomes
Summary: In this study, a hydrophobic laser-induced graphene-based nitrate ion-selective electrode is developed to address the current issues in solid-contact ion-selective electrodes. The electrode shows comparable performance to a US Environmental Protection Agency-accepted analytical method for water quality analysis.
Article
Chemistry, Analytical
Christopher J. Freeman, Borkat Ullah, Md. Shafiul Islam, Maryanne M. Collinson
Summary: Potentiometric redox sensing is a relatively inexpensive and passive method for evaluating the overall redox state of complex biological and environmental solutions. This study focuses on the fabrication of miniaturized nanoporous gold electrodes for potentiometric redox sensing of biologically relevant redox molecules in microliter volumes. Results show that the redox potential of solutions containing biologically relevant concentrations of ascorbic acid, uric acid, and cysteine is strongly influenced by ascorbic acid at NPG electrodes.
Article
Biochemistry & Molecular Biology
Chunxian Liao, Lijie Zhong, Yitian Tang, Zhonghui Sun, Kanglong Lin, Longbin Xu, Yan Lyu, Dequan He, Ying He, Yingming Ma, Yu Bao, Shiyu Gan, Li Niu
Summary: This study compared the performance of ISM-free Ag/AgCl electrode with ISM-based SC-ISE, revealing that the former has better selectivity for organic chloride ionophores and overall performance. Additionally, Ag/AgX electrodes can also be applied for sensing single and multi-valent anions.
Review
Chemistry, Analytical
Celeste R. Rousseau, Philippe Buhlmann
Summary: Research in recent years has focused on the development of solid-contact ISEs for calibration-free measurements in long-term, in situ analysis. This review discusses the definition of calibration-free usage and relevant literature, with a focus on different mechanisms of ion-to-electron signal transduction and different types of transduction modes.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2021)
Article
Electrochemistry
Omer Isildak, Ilyas Yildiz
Summary: A new all-solid-state PVC membrane nitrate electrode was developed and used for potentiometric analysis of nitrate ions. The electrode utilized silver (I) bisdiethyldithiocarbamate ((C2H5)2NCS2)2Ag+) (Ag(dtc)2) compound as the electroactive positive charged carrier (ionophore) in a plasticized PVC membrane structure. The nitrate-ISE exhibited linear potentiometric behavior in the concentration range of nitrate ions with a detection limit of 6.71 x 10-6 mol L-1. It was successfully applied for the determination of nitrate ions in different water samples and fruit juices, although its pH working range is limited to 4 - 9.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Analytical
Antonio Calvo-Lopez, Eva Arasa-Puig, Julian Alonso-Chamarro, Mar Puyol
Summary: Various causes can disrupt the balance between intracellular and extracellular mechanisms, leading to abnormal blood potassium levels. This can have serious consequences, including life-threatening situations. Early diagnosis, treatment, and monitoring are crucial for minimizing the impact on patients. However, bedside blood potassium testing is not widely available, especially in emerging countries. To address this issue, we have developed a portable and cost-effective potentiometric point-of-care microsystem. This microsystem combines microfluidics with a potentiometric technique using a potassium selective electrode with an improved polymeric membrane. It has a small size, comparable to a credit card, and provides accurate and rapid potassium measurements. The device has been tested using human serum samples and shown to produce results comparable to established methods. This highlights the potential of the developed microanalyzer for bedside health applications.
Article
Chemistry, Analytical
Kanyapat Teekayupak, Atchara Lomae, Ismail Agir, Natthaya Chuaypen, Thasinas Dissayabutra, Charles S. Henry, Orawon Chailapakul, Tugba Ozer, Nipapan Ruecha
Summary: Despite recent developments in manufacturing technologies, there is still a significant bottleneck for mass-production of ion-selective electrodes (ISEs). In this study, a fully-automated system for large-scale production of ISEs was presented, using polyvinyl chloride, polyethylene terephthalate, and polyimide as substrates, and stencil printing, screen-printing, and laser engraving as fabrication techniques. Sensitivities of the ISEs were compared to determine the best material, and carbon nanomaterials were used for surface modification to enhance sensitivities. An automated 3D-printed robot was utilized for the drop-cast procedure during ISE fabrication. The developed sensing platform offers low-cost detection of electrolytes for point-of-care applications.
Article
Chemistry, Analytical
Rimeh Ismail, Ivana Sedenkova, Zulfiya Cernochova, Iryna Romanenko, Ognen Pop-Georgievski, Martin Hruby, Elena Tomsik
Summary: We developed a sensor that can rapidly detect the presence of Fe2+ and/or Fe3+ ions with high selectivity and stability, functioning reliably in a biological environment.
Article
Chemistry, Analytical
Qiyi He, Mark R. McCoy, Huiyi Yang, Mingxia Lin, Xiping Cui, Suqing Zhao, Christophe Morisseau, Dongyang Li, Bruce D. Hammock
Summary: In this study, a mix-and-read assay based on split-luciferase detection and anti-sEH nanobodies was developed for the detection of human sEH. The assay showed high sensitivity and a wide linear range, with a fast and easy procedure.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Naruto Miyakawa, Ayumi Shinagawa, Tomomi Nakano, Shota Ushiba, Takao Ono, Yasushi Kanai, Shinsuke Tani, Masahiko Kimura, Kazuhiko Matsumoto
Summary: Graphene is a promising platform for sensing biomolecule charges. We proposed a graphene chemiresistor enzyme immunoassay that can detect all protein types with high sensitivity.
MICROCHEMICAL JOURNAL
(2024)
Article
Chemistry, Multidisciplinary
Xingxing Xu, Yingtao Yu, Qitao Hu, Si Chen, Leif Nyholm, Zhen Zhang
Summary: Label-free potentiometric detection of DNA molecules using a field-effect transistor (FET) with a gold gate offers a platform for rapid, straightforward, and inexpensive analyses of nucleic acid samples. The potential of the gold-sensing electrode is determined by the mixed potential of the gold-thiol and gold-oxygen redox interactions, creating a redox buffer effect that suppresses the potentiometric signal induced by DNA hybridization. Similar redox buffer effects may be present in other types of potentiometric detections of biomarkers based on thiol-gold chemistry.
Article
Chemistry, Analytical
Zhaoyang Lin, Rongning Liang, Wei Qin
Summary: This study investigates the feasibility of using polymeric membrane ion-selective electrodes (ISEs) in nonaqueous media. The results show that the aprotic solvent acetonitrile has the strongest destructive ability towards the sensing performance of the ISE, while the effect on the sensing performance depends on the kind of protic solvent, the immersion time, and the polarity of the membrane plasticizer. These findings are important for expanding the application scope of ISEs.
Article
Chemistry, Analytical
Hitoshi Mizuguchi, Soma Fujiki, Takaki Shibata, Masatsugu Oishi, Masamitsu Iiyama, Toshio Takayanagi, Yu-Chi Lin, Min-Hsin Yeh
Summary: A flow-based, enzyme-free biosensor for selective and sensitive determination of uric acid was developed using track-etched membrane electrodes. The sensor system consisted of a pre-reactor electrode for decomposing interfering species and a detector electrode for uric acid detection. The sensor system showed improved sensitivity with the introduction of acetylene black as an electrode catalyst. The system also successfully eliminated interference from co-existing L-ascorbic acid using 2-aminoethanethiol-modified Au-TEMEs as pre-reactor electrodes.
SENSORS AND ACTUATORS B-CHEMICAL
(2023)
Article
Chemistry, Analytical
Tingting Han, Andrey Kalinichev, Zekra Mousavi, Konstantin N. Mikhelson, Johan Bobacka
Summary: This work characterized the potentiometric response of solid-contact ion-selective electrodes with thin-layer ion-selective membranes. The anomalous increase in potential at low concentrations of the primary potassium ion was found to be influenced by the solid-contact material, thickness of the membrane, and timescale of the measurement. It was concluded that the anomalous response is a characteristic feature of these electrodes and can be used as a diagnostic tool.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Chemistry, Analytical
Soma Papp, Jozsef Kozma, Tom Lindfors, Robert E. Gyurcsanyi
Article
Chemistry, Analytical
Laszlo Simon, Zsofia Bognar, Robert E. Gyurcsanyi
Article
Biochemistry & Molecular Biology
Zoltan Janos Tolnai, Judit Andras, Zsuzsanna Szeitner, Krisztina Percze, Laszlo Ferenc Simon, Robert E. Gyurcsanyi, Tamas Meszaros
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2020)
Review
Biochemistry & Molecular Biology
Zsofia Bognar, Robert E. Gyurcsanyi
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2020)
Article
Electrochemistry
Jozsef Kozma, Soma Papp, Robert E. Gyurcsanyi
Summary: By introducing ferrocenefunctionalized multi-walled carbon nanotubes, it is possible to add redox properties to purely capacitive solid contacts, thereby aiding in further controlling the standard potential of SCISEs.
ELECTROCHEMISTRY COMMUNICATIONS
(2021)
Article
Electrochemistry
Giorgio Caserta, Xiaorong Zhang, Aysu Yarman, Eszter Supala, Ulla Wollenberger, Robert E. Gyurcsanyi, Ingo Zebger, Frieder W. Scheller
Summary: This study explores the preparation of peptide-imprinted polymer nanofilms for selective recognition of human adult hemoglobin, utilizing a hierarchical approach with superior affinity and providing key mechanistic insights towards the stability of the formed MIPs.
ELECTROCHIMICA ACTA
(2021)
Article
Chemistry, Analytical
Marek Debosz, Jozsef Kozma, Radoslaw Porada, Marcin Wieczorek, Justyna Paluch, Robert E. Gyurcsanyi, Jan Migdalski, Pawel Koscielniak
Summary: Urinalysis is a simple and non-invasive method for diagnosing and monitoring various health disorders. By integrating sensors with 3D printed devices, cost-effectiveness can be ensured for widespread use in measuring multiple parameters.
Article
Chemistry, Analytical
Xiaorong Zhang, Giorgio Caserta, Aysu Yarman, Eszter Supala, Armel F. Tadjoung Waffo, Ulla Wollenberger, Robert E. Gyurcsanyi, Ingo Zebger, Frieder W. Scheller
Summary: The study utilized epitope imprinting polymers to recognize parent proteins, revealing non-specific binding between target peptides and parent proteins, as well as stronger non-specific binding of HbA to MIPs than target peptides.
Article
Chemistry, Multidisciplinary
Zsofia Bognar, Marien de Jonge, Robert E. Gyurcsanyi
Summary: In situ labelling and encapsulation of viruses with silver nanoparticles enables their detection and quantification at the single particle level. Electrochemical measurement of the current peaks from the silver-coated viruses on the electrode allows for the linear correlation between frequency and virus count.
Article
Chemistry, Multidisciplinary
Zsofia Bognar, Eszter Supala, Aysu Yarman, Xiaorong Zhang, Frank F. Bier, Frieder W. Scheller, Robert E. Gyurcsanyi
Summary: This study presents a versatile approach for generating epitope-imprinted polymer-based microarrays for protein recognition on surface plasmon resonance imaging (SPRi) chips, which can rapidly screen binding kinetics of various targets, including the SARS-CoV-2 spike protein. The highly affine molecularly imprinted polymers (MIPs) developed in this study showed lower nanomolar dissociation constants for RBD, exceeding natural affinity levels and even binding SARS-CoV-2 virus particles with higher affinity.
Article
Chemistry, Analytical
Jozsef Kozma, Soma Tapp, Robert E. Gyurcsanyi
Summary: In this study, a new class of solid-contact material based on the covalent functionalization of multiwalled carbon nanotubes with a chemically stable redox molecule was proposed. This material showed excellent reproducibility and stability for potassium ion measurements, with no sensitivity towards O-2, CO2, and light.
ANALYTICAL CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Jozsef Kozmaa, Soma Papp, Robert E. Gyurcsanyia
Summary: Solid-contact ion-selective electrodes (SCISEs) are the best electrode embodiment for miniaturized, wearable and disposable sensors for ion/electrolyte measurements in body fluids. However, large scale manufacturing with reproducible calibration parameters is a challenge for SCISEs. The galvanostatic intermittent titration technique (GITT) is introduced to determine the optimal preadjustment potential.
BIOELECTROCHEMISTRY
(2023)
Article
Chemistry, Analytical
Zsofia Bognar, Jozsef Kozma, Norbert Kovacs, Robert E. Gyurcsanyi
Summary: In order to overcome the lack of diversity in functional monomers for protein-selective molecularly imprinted polymers (MIPs), a new concept of conjugating an electropolymerizable monomer unit (umbelliferone) to an amino acid has been introduced. A novel aspartate-umbelliferone (Asp-UMB) conjugate has been synthesized as the first representative of this class of monomers and its suitability to generate highly affine MIPs for proteins by epitope imprinting has been proven. MIP microarrays on surface plasmon resonance imaging (SPRi) chips were used to optimize and assess the binding kinetics, resulting in highly affine MIPs with equilibrium dissociation constants in the lower picomolar range.
Editorial Material
Chemistry, Analytical
Eric Bakker, Philippe Buhlmann, J. Justin Gooding, Robert E. Gyurcsanyi, Ernoe Pretsch
Article
Chemistry, Multidisciplinary
Xiaorong Zhang, Armel T. Waffo, Aysu Yarman, Norbert Kovacs, Zsofia Bognar, Ulla Wollenberger, Ibrahim M. El-Sherbiny, Rabeay Y. A. Hassan, Frank F. Bier, Robert E. Gyurcsanyi, Ingo Zebger, Frieder W. Scheller
Summary: This study aims to gain a mechanistic understanding of the formation of epitope-imprinted polymer nanofilms. The affinity towards different peptides is mainly determined by a four-amino acid motif present in the template peptide. However, the parent proteins RBD and spike protein exhibit higher affinity on the nanofilm surface.
