Permselectivity and Dopamine Detection with Pt Electrodes Covered with PAA-Modified Porous Silicate Film

2019 ◽  
Vol 166 (2) ◽  
pp. H19-H24 ◽  
Author(s):  
Dongmei Wang ◽  
Hongying Xian ◽  
Rui Wang ◽  
Yongxin Li
Keyword(s):  
Dopamine Detection ◽  
Silicate Film ◽  
Pt Electrodes ◽  
Porous Silicate

scholarly journals Monitoring Contractile Cardiomyocytes via Impedance Using Multipurpose Thin Film Ruthenium Oxide Electrodes

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1433
Author(s):  
Esther Tanumihardja ◽  
Douwe S. de Bruijn ◽  
Rolf H. Slaats ◽  
Wouter Olthuis ◽  
Albert van den Berg
Keyword(s):  
Thin Film ◽  
Electrical Impedance ◽  
Ruthenium Oxide ◽  
Electrical Impedance Spectroscopy ◽  
Visual Data ◽  
Oxide Electrodes ◽  
Pt Electrodes ◽  
Mode Of Operation ◽  
Frequency Components

A ruthenium oxide (RuOx) electrode was used to monitor contractile events of human pluripotent stem cells-derived cardiomyocytes (hPSC-CMs) through electrical impedance spectroscopy (EIS). Using RuOx electrodes presents an advantage over standard thin film Pt electrodes because the RuOx electrodes can also be used as electrochemical sensor for pH, O2, and nitric oxide, providing multisensory functionality with the same electrode. First, the EIS signal was validated in an optically transparent well-plate setup using Pt wire electrodes. This way, visual data could be recorded simultaneously. Frequency analyses of both EIS and the visual data revealed almost identical frequency components. This suggests both the EIS and visual data captured the similar events of the beating of (an area of) hPSC-CMs. Similar EIS measurement was then performed using the RuOx electrode, which yielded comparable signal and periodicity. This mode of operation adds to the versatility of the RuOx electrode’s use in in vitro studies.

scholarly journals The UV Effect on the Chemiresistive Response of ZnO Nanostructures to Isopropanol and Benzene at PPM Concentrations in Mixture with Dry and Wet Air

Chemosensors ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 181
Author(s):  
Maksim A. Solomatin ◽  
Olga E. Glukhova ◽  
Fedor S. Fedorov ◽  
Martin Sommer ◽  
Vladislav V. Shunaev ◽  
...  
Keyword(s):  
Binding Energies ◽  
Zno Nanostructures ◽  
Gas Detectors ◽  
Dry Air ◽  
Uv Illumination ◽  
Pt Electrodes ◽  
Electrochemical Deposition Method ◽  
Metal Oxide Gas Sensors ◽  
On Chip ◽  
Wide Operating

Towards the development of low-power miniature gas detectors, there is a high interest in the research of light-activated metal oxide gas sensors capable to operate at room temperature (RT). Herein, we study ZnO nanostructures grown by the electrochemical deposition method over Si/SiO2 substrates equipped by multiple Pt electrodes to serve as on-chip gas monitors and thoroughly estimate its chemiresistive performance upon exposing to two model VOCs, isopropanol and benzene, in a wide operating temperature range, from RT to 350 °C, and LED-powered UV illumination, 380 nm wavelength; the dry air and humid-enriched, 50 rel. %, air are employed as a background. We show that the UV activation allows one to get a distinctive chemiresistive signal of the ZnO sensor to isopropanol at RT regardless of the interfering presence of H2O vapors. On the contrary, the benzene vapors do not react with UV-illuminated ZnO at RT under dry air while the humidity’s appearance gives an opportunity to detect this gas. Still, both VOCs are well detected by the ZnO sensor under heating at a 200–350 °C range independently on additional UV exciting. We employ quantum chemical calculations to explain the differences between these two VOCs’ interactions with ZnO surface by a remarkable distinction of the binding energies characterizing single molecules, which is −0.44 eV in the case of isopropanol and −3.67 eV in the case of benzene. The full covering of a ZnO supercell by H2O molecules taken for the effect’s estimation shifts the binding energies to −0.50 eV and −0.72 eV, respectively. This theory insight supports the experimental observation that benzene could not react with ZnO surface at RT under employed LED UV without humidity’s presence, indifference to isopropanol.

Turn-on fluorescent probe for dopamine detection in solutions and live cells based on in situ formation of aminosilane-functionalized carbon dots

2021 ◽  
Vol 1157 ◽  
pp. 338394
Author(s):  
Xiao-Yue Tang ◽  
Yi-Ming Liu ◽  
Xiao-Lin Bai ◽  
Hao Yuan ◽  
Yi-Kao Hu ◽  
...  
Keyword(s):  
Fluorescent Probe ◽  
Carbon Dots ◽  
Live Cells ◽  
Turn On ◽  
Dopamine Detection ◽  
In Situ Formation

Fabrication of bisferrocenyl derivative grafted HTPB with high iron content and its application in dopamine detection

2021 ◽  
pp. 121789
Author(s):  
Alireza Aghaiepour ◽  
Shabnam Rahimpour ◽  
Elmira Payami ◽  
Reza Mohammadi ◽  
Reza Teimuri-Mofrad
Keyword(s):  
Iron Content ◽  
High Iron Content ◽  
High Iron ◽  
Dopamine Detection

scholarly journals Mixed Lithium and Sodium Ion Aprotic DMSO Electrolytes for Oxygen Reduction on Au and Pt Studied by DEMS and RRDE

2021 ◽  
Author(s):  
M. Hegemann ◽  
P. P. Bawol ◽  
A. Köllisch-Mirbach ◽  
H. Baltruschat
Keyword(s):  
Oxygen Reduction ◽  
Product Distribution ◽  
Reduction Reaction ◽  
Mixed Electrolytes ◽  
Peroxide Formation ◽  
Pt Electrode ◽  
Rate Determining Step ◽  
Differential Electrochemical Mass Spectrometry ◽  
Redox Couples ◽  
Pt Electrodes

AbstractIn order to advance the development of metal-air batteries and solve possible problems, it is necessary to gain a fundamental understanding of the underlying reaction mechanisms. In this study we investigate the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER, from species formed during ORR) in Na+ containing dimethyl sulfoxide (DMSO) on poly and single crystalline Pt and Au electrodes. Using a rotating ring disk electrode (RRDE) generator collector setup and additional differential electrochemical mass spectrometry (DEMS), we investigate the ORR mechanism and product distribution. We found that the formation of adsorbed Na2O2, which inhibits further oxygen reduction, is kinetically favored on Pt overadsorption on Au. Peroxide formation occurs to a smaller extent on the single crystal electrodes of Pt than on the polycrystalline surface. Utilizing two different approaches, we were able to calculate the heterogeneous rate constants of the O2/O2− redox couple on Pt and Au and found a higher rate for Pt electrodes compared to Au. We will show that on both electrodes the first electron transfer (formation of superoxide) is the rate-determining step in the reaction mechanism. Small amounts of added Li+ in the electrolyte reduce the reversibility of the O2/O2− redox couples due to faster and more efficient blocking of the electrode by peroxide. Another effect is the positive potential shift of the peroxide formation on both electrodes. The reaction rate of the peroxide formation on the Au electrode increases when increasing the Li+ content in the electrolyte, whereas it remains unaffected on the Pt electrode. However, we can show that the mixed electrolytes promote the activity of peroxide oxidation on the Pt electrode compared to a pure Li+ electrolyte. Overall, we found that the addition of Li+ leads to a Li+-dominated mechanism (ORR onset and product distribution) as soon as the Li+ concentration exceeds the oxygen concentration. Graphical abstract

Ionic liquid tuned titanium dioxide nanostructures as an efficient colorimetric sensing platform for dopamine detection

2021 ◽  
Vol 262 ◽  
pp. 124289
Author(s):  
Umar Nishan ◽  
Ujala Sabba ◽  
Abdur Rahim ◽  
Muhammad Asad ◽  
Mohibullah Shah ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Titanium Dioxide ◽  
Colorimetric Sensing ◽  
Dopamine Detection ◽  
Sensing Platform
Sign in / Sign up

Export Citation Format

Share Document