• Title/Summary/Keyword: electrochemical sensing

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Metal Nano Particle modified Nitrogen Doped Amorphous Hydrogenated Diamond-Like Carbon Film for Glucose Sensing

  • Zeng, Aiping;Jin, Chunyan;Cho, Sang-Jin;Seo, Hyun-Ook;Lim, Dong-Chan;Kim, Doo-Hwan;Hong, Byung-You;Boo, Jin-Hyo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.434-434
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    • 2011
  • Electrochemical method have been employed in this work to modify the chemical vapour deposited nitrogen doped hydrogen amorphous diamond-like carbon (N-DLC) film to fabricate nickel and copper nano particle modified N-DLC electrodes. The electrochemical behaviour of the metal nano particle modified N-DLC electrodes have been characterized at the presence of glucose in electrolyte. Meanwhile, the N-DLC film structure and the morphology of metal nano particles on the N-DLC surface have been investigated using micro-Raman spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy. The nickel nano particle modified N-DLC electrode exhibits a high catalytic activity and low background current, while the advantage of copper modified N-DLC electrode is drawn back by copper oxidizations at anodic potentials. The results show that metal nano particle modification of N-DLC surface could be a promising method for controlling the electrochemical properties of N-DLC electrodes.

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Recent Advances in Electrochemical Studies of π-Conjugated Polymers

  • Park, Su-Moon;Lee, Hyo-Joong
    • Bulletin of the Korean Chemical Society
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    • v.26 no.5
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    • pp.697-706
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    • 2005
  • We review the evolution of electrochemical studies of conducting polymers into the current state-of-the-art based primarily on our work. While conventional electrochemical experiments sufficed for the needs in the phase of studies of both electrochemical synthesis and characterization of conducting polymers, developments of various new experimental techniques have led to their introduction to this field for more refined information. As a result, the conventional electrochemical, spectroelectrochemical, electrochemical quartz crystal microbalance, impedance, and morphological as well as electrical characterization studies all made important contributions to a better understanding of the polymerization mechanisms and the conductive properties of these classes of polymers. From this review, we hereby expect that the electrochemical techniques will continue to play important roles in bringing this field to the practical applications such as nanoscale electronic devices.

Concurrent Electrocatalysis and Sensing of Hydrazine and Sulfite and Nitrite Ions using Electrodeposited Gold Nanostructure-Modified Electrode

  • Seo, Yeji;Manivannan, Shanmugam;Kang, Inhak;Shin, Woo-Seung;Kim, Kyuwon
    • Journal of Electrochemical Science and Technology
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    • v.8 no.1
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    • pp.25-34
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    • 2017
  • Concurrent electrocatalysis and sensing of hydrazine, sulfite ions, and nitrite ions in a mixture were studied using electrodes modified by electrodeposited Au nanostructures (NSs). The ${\beta}$-cyclodextrin-mixed silicate sol-gel composite was drop-casted on the electrode surface and nucleation guided by ${\beta}$-cyclodextrin occurred, followed by the electrodeposition of Au NSs. The additive, ${\beta}$-cyclodextrin, played an evident role as a structure-directing agent; thus, small raspberry-like Au NSs were obtained. The modified electrodes were characterized by surface characterization techniques and electrochemical methods. The Au NSs-modified electrodes effciently electrocatalyzed the oxidation of toxic molecules such as hydrazine and sulfite and nitrite ions even in the absence of any other electron transfer mediator or enzyme immobilization. Well-resolved oxidation peaks along with decreased overpotentials were noticed during the electrooxidation process. The fabricated Au nanostructured electrode clearly distinguished the electrooxidation peaks of each of the three analytes from their mixture.

Assembly of chemically reduced graphene oxide with folic acid functionalized with pyrene moieties and electrochemical sensing of folate receptors

  • Kwon, Binhee;Park, Jongyeap;Jeong, Woojun;Jeong, Guembi;Ryu, Hyeong Seon;Paoprasert, Peerasak;Park, Sung Young;In, Insik
    • Carbon letters
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    • v.27
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    • pp.26-34
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    • 2018
  • To formulate folate receptor (FR)-specific graphene-based electrochemical electrodes, a folic acid (FA) derivative attached with two pyrene molecules on the glutamate tail of FA was synthesized. The resulting pyrene-functionalized FA (FA-Py) presented the spontaneous noncovalent binding on chemically reduced graphene oxides (rGO) through an ${\pi}-{\pi}$ interaction. Ultrathin morphology, high water-resistance, and preservation of intact FR-specific pteroates from the rGO/FA-Py assembly allow this assembly to be exploited as robust and FR-specific electrochemical electrode materials. The limits of detecting rGO/FA-Py modified electrodes were found to be as low as 3.07 nM in FR concentrations in cyclic voltammetry analysis.

Quasi-Solid-State Hybrid Electrolytes for Electrochemical Hydrogen Gas Sensor

  • Kim, Sang-Hyung;Han, Dong-Kwan;Hong, SeungBo;Jeong, Bo Ra;Park, Bok-Seong;Han, Sang-Do;Kim, Dong-Won
    • Journal of Electrochemical Science and Technology
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    • v.10 no.3
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    • pp.294-301
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    • 2019
  • The quasi-solid-state hybrid electrolytes were synthesized by chemical cross-linking reaction of methacrylate-functionalized $SiO_2$ ($MA-SiO_2$) and tetra (ethylene glycol) diacrylate in aqueous electrolyte. A quasi-solid-state electrolyte synthesized by 6 wt.% $MA-SiO_2$ exhibited a high ionic conductivity of $177mS\;cm^{-1}$ at room temperature. The electrochemical $H_2$ sensor assembled with quasi-solid-state electrolyte showed relatively fast response and high sensitivity for hydrogen gas at ambient temperature, and exhibited better durability and stability than the liquid electrolyte-based sensor. The simple construction of the sensor and its sensing characteristics make the quasi-solid-state hydrogen sensor promising for practical application.

Spinel Nanoparticles ZnCo2O4 as High Performance Electrocatalyst for Electrochemical Sensing Antibiotic Chloramphenicol

  • Van-Cuong Nguyen;HyunChul Kim
    • Journal of Electrochemical Science and Technology
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    • v.15 no.1
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    • pp.152-160
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    • 2024
  • In this study, ZnCo2O4 nanoparticles were synthesized via the coprecipitation method using different annealing temperatures from 200℃ to 800℃. By varying the treatment temperature, the morphology changed from amorphous to tetragonal, and finally to polygonal particles. As temperature increased, the sizes of the nanoparticles also changed from 5 nm at 200℃ to approximately 500 nm at 800℃. The fabricated material was used to modify the working electrode of a screen-printed carbon electrode (SPE), which was subsequently used to survey the detection performance of the antibiotic, chloramphenicol (CAP). The electrochemical results revealed that the material exhibits a good response to CAP. Further, the sample that annealed at 600℃ displayed the best performance, with a linear range of 1-300 μM, and a limit of detection (LOD) of 0.15 μM. The sensor modified with ZnCo2O4 also exhibited the potential for utilitarian application when the recovery in a real sample was above 97%.

Electrochemical Sensing Property of Harbor Pollutants using Viologen Derivative (Viologen 유도체를 이용한 항만오염물질의 전기화학적 특성)

  • Choi, Yong-Sung;Ji, Yoo-Kang;Park, Soo-Bong;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.997-999
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    • 2008
  • In this paper, viologen derivative is used as charge transfer material to develop sensors for detecting the organic pollutants which are the main reason of harbor pollution. We fabricated self-assembled monolayers of viologen derivative on gold electrode of QCM and investigated an electrochemical behavior property. We also determined electrochemical sensing property about environmental pollution materials such as bezene, phosphate and surfactant through quantitative and qualitative analysis of charge transfer using intrinsic property of viologen derivative by temperature and concentration change. From the achieved results, we can apply and develope the detecting sensors for harbor pollutants.

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Simple and Sensitive Electrochemical Sandwich-type Immunosensing of Human Chorionic Gonadotropin based on b-cyclodextrin Functionalized Graphene

  • Linfen Xu;Ling liu;Xiaoyan Zhao;Jinyu Lin;Shaohan Xu;Jinlian He;Debin Jiang;Yong Xia
    • Journal of Electrochemical Science and Technology
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    • v.14 no.1
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    • pp.51-58
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    • 2023
  • The effective detection of human chorionic gonadotropin (HCG) is considerably important for the clinical diagnosis of both of early pregnancy and nonpregnancy-related diseases. In this work, a simple and sensitive electrochemical sandwich-type immunosensing platform was designed by synthesizing b-cyclodextrin (CD) functionalized graphene (CD/GN) hybrid as simultaneously sensing platform and signal transducer coupled with rhodamine b (RhB) as probe. In brief, GN offers large surface area and high conductivity, while CD exhibits superior host-guest recognition capability, thus the primary antibody (Ab1) of HCG can be bound into the cavities of CD/GN to form stable Ab1/CD/GN inclusion complex; meanwhile, the secondary antibody (Ab2) and RhB can also enter into the cavities, producing RhB/Ab2/CD/GN complex. Then, by using Ab1/CD/GN as sensing platform and RhB/Ab2/CD/GN as signal transducer (in which RhB was signal probe), a simple sandwich-type immunosensor was constructed. Under the optimum parameters, the designed immunosensor exhibited a considerable low analytical detection of 1.0 pg mL-1 and a wide linearity of 0.002 to 10.0 ng mL-1 for HCG, revealing the developed sandwich-type electrochemical immunosensing platform offered potential real applications for the determination of HCG.