• 센서학회지
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• 제19권6호
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• pp.421-427
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• 2010

Alizarin Red S modified screen printed carbon electrodes were developed for the electrochemical detection of aluminum ion. The electrodes developed use screen-printed carbon electrodes(SPCEs) coupled with chemical modification with an organic chelator, Alizarin Red S(ARS), for aluminum ion detection in aqueous solution. For sensor fabrication ARS was directly immobilized on the surface of SPCEs using PVA-SbQ(The poly(vinyl alcohol) bearing stryrylpyridinium groups). Aluminum concentrations were indirectly estimated by amperometric determination of the non-complexed ARS immobilized on the electrodes, after its complexation with aluminum. The sensitivity of the sensor developed was $3.8\;nA{\mu}M^{-1}cm^{-2}$ and the detection limit for aluminum was $25\;{\mu}M$.

• 전기화학회지
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• 제10권3호
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• pp.229-232
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• 2007

An amperometric immunosensor for the determination of rabbit IgG is proposed. The immunoassay utilizes a screen-printed carbon electrode on which osmium redox polymer is electrodeposited. This immunoassay detects 0.1 ng/ml of rabbit IgG, which is ${\sim}10^2$ fold higher than the most sensitive enzyme amplified amperometric immunoassay. The assay utilizes a screen-printed carbon electrode which was pre-coated by a co-electrodeposited film of an electron conducting redox hydrogel and a rabbit IgG. The rabbit IgG in the electron conducting film conjugates captures, when present, the anti-rabbit IgG. The captured anti-rabbit-IgG is labeled with horseradish peroxidase (HRP) which catalyzes the two-electron reduction of $H_2O_2$ to water. Because the redox hydrogel electrically connects HRP reaction centers to the electrode, completion of the sandwich converts the film from non-electrocatalytic to electro-catalytic for the reduction of $H_2O_2$ to $H_2O$ when the electrode is poised at 200 mV vs. Ag/AgCl.

• 분석과학
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• 제12권3호
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• pp.218-223
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• 1999

스크린 프린팅 기술을 이용하여 일회용 에탄올 센서를 개발하고 전기화학적 방법으로 그 성능을 조사하였다. 일회용 에탄올 센서는 폴리에스테르 기질 위에 탄소와 은 반죽 그리고 절연체 잉크로 작업 및 기준전극의 감응부위와 전기적 접촉부위의 형상을 차례로 인쇄한 후 알코올탈수소효소(ADH) 또는 알코올산화효소(AOD)를 알려진 전자전달 매개체(mediator)와 함께 작업전극에 고정시켜 제작하였다. 일회용 센서의 제작 과정에서 감응도와 재현성을 높이기 위하여 프린팅한 탄소 작업전극을 전처리 하는 몇 가지 방법들을 적용하고 그 결과들을 비교하였다. 제작된 일회용 센서는 소량의 혈액시료로 음주측정을 하는데, 그리고 발효공정 제어 등에 유용하게 사용될 수 있다.

• 공업화학
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• 제34권5호
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• pp.493-500
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• 2023

본 연구에서는 스크린 프린팅 공정을 통해 탄소 잉크 기반의 2상 전극을 제작하고, 전극 표면에 이리듐 산화물(IrO_x)을 코팅함으로써 전극의 분극 현상을 제어할 수 있는 임피던스 센서를 개발하였다. IrO_x는 순환 전압 전류법으로 탄소 전극의 표면 위에 순환 수(0~50 cycles)에 따라서 코팅되었다. 전자주사현미경을 이용하여 cycle 수가 증가할수록 IrO_x 입자의 크기와 수가 증가하는 경향성을 확인하였다. 전기화학 임피던스 분석을 이용하여 상기 제조된 센서들의 NaCl 농도에 따른 임피던스 변화 값을 조사하였다. 50 cycle에서 제조된 센서가 가장 우수한 결정계수와 재현성을 나타내었으며, 이는 분극 현상이 잘 제어되었기 때문이다. 실제 용액 샘플들을 이용한 삼투압 장비와 비교 측정 실험을 수행함으로써 IrO_x 기반 센서의 안구건조증 진단 센서로의 활용가치를 증명하였다.

• 센서학회지
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• 제20권1호
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• pp.35-39
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• 2011

A disposable electrochemical immunosensor system has been developed for the detection of herbicide in aqueous samples. Disposable screen printed carbon electrodes(SPCE) were used as basic electrodes and an enzyme, horseradish peroxidase (HRP), and anti-herbicide antibodies was immobilised on to the working electrode of SPCE by using avidin-biotin coupling reactions. An herbicide-glucose oxidase conjugates have been used for the competitive immunoreaction with sample herbicides. The enzymatic reaction between the conjugated glucose oxidase and glucose added generates hydrogen peroxide, which was reduced by the peroxidase immobilised. The latter process caused an electrical current change, due to direct re-reduction of peroxidase by a direct electron transfer mechanism, which was measured to determine the herbicides in the sample. The optimal operational condition was found to be: $20\;{\mu}gl-1$ deglycosylated avidin loading to the working electrode and working potential +50 mV vs. Ag/AgCl. The total assay time was 15 min after sample addition. The detection limits for herbicides, atrazine and simazine, were found to be 3 ppb and 10 ppb, respectively.

• 전기화학회지
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• 제7권1호
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• pp.44-48
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• 2004

The two-component type enzyme amplified amperometric DNA assay is described to use an ambient $O_2$ of the substrate of the DNA labeling enzyme. Although the assay detects DNA only at > 0.5M concentration, a concentration $\~10^6$ fold higher than the sandwich-type enzyme amplified amperometric DNA assay, it can be run with an always available substrate. The assay utilizes screen-printed carbon electrodes (SPEs) which were pre-coated by a co-electrodeposited film of an electron conducting redox hydrogel and a 37-base long single-stranded DNA sequence. The DNA in the electron conducting film hybridizes and captures, when present, the 37-base long detection-DNA, which is labeled with bilirubin oxidase (BOD), an enzyme catalyzing the four-electron reduction of $O_2$ to water. Because the redox hydrogel electrically connects the BOD reaction centers to the electrode, completion of the sandwich converts the film from non-electrocatalytic to electrocatalytic for the reduction of $O_2$ to water when the electrode is poised at 200 mV vs. Ag/hgCl. The advantage or the assay over the earlier reported sandwich type enzyme amplified amperometric DNA assay, in which the amplifying enzyme was horseradish peroxidase, is that it utilizes ambient $O_2$ instead of the less stable and naturally unavailable $H_2O_2$.

• 한국표면공학회지
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• 제56권1호
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• pp.40-54
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• 2023

In this work, we synthesized a novel electrochemical sensing materials based on tetracarboxylic copper phthalocyanine (TcCuPtc) conjugated PANI (TcCuPtc@PANI). The synthesized materials were employed to modify the screen-printed carbon electrode (SPCE) for the selective sensing of 4-nitrophenol. The TcCuPtc was conjugated with conducting polymer of PANI through the electrostatic interaction and π-π electron conjugation, the polymer film of PANI to inhibit the leakage of TcCuPtc from the surface of the electrode. The prepared TcCuPtc@PANI were characterized and confirmed by scanning electron microscopy (SEM) with EDX, ATR-IR, UV-vis absorption spectroscopy, cyclic voltammetry, and differential pulse voltammetry techniques. The prepared TcCuPtc@PANI/SPCE showed an excellent electrocatalytic sensing of 4-NP in the linear concentrations from 3 to 500 nM with a LOD of 0.03 nM and a sensitivity of 8.8294 ㎂/nM cm^-2. However, the prepared TcCuPtc@PANI/SPCE showed selective sensing of 4-NP in the presence of other interfering species. The practical applicability of the TcCuPtc@PANI/SPCE was employed for the sensing of 4-NP in different water samples by standard addition method and showed satisfactory recovery results.

• Journal of Electrochemical Science and Technology
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• 제4권4호
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• pp.146-152
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• 2013

We demonstrate that carbon electrodes screen-printed directly on cellulose paper can be employed to perform bipolar electrochemistry. In addition, an array of 18 screen-printed bipolar electrodes (BPEs) can be simultaneously controlled using a single pair of driving electrodes. The electrochemical state of the BPEs is read-out using electrogenerated chemiluminescence. These results are important because they demonstrate the feasibility of coupling bipolar electrochemistry to microfluidic paperbased analytical devices (${\mu}PADs$) to perform highly multiplexed, low-cost measurements.

• Transactions on Electrical and Electronic Materials
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• 제6권4호
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• pp.140-143
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• 2005

Carbon Nanotube(CNTs) counter electrode is a promising alternative to Platinum counter electrode for dye sensitized solar cells (DSSCs). In this study, CNT counter electrodes having different visible light transmittance were prepared on fluorine-doped tin oxide (FTO) glass surface by spray coating method. Microstructural images show that there are CNT-tangled region coated on FTO glass counter electrodes. Using such CNT counter electrodes and screen printed $TiO_2$ electrodes, DSSCs were assembled and its I-V characteristics have been studied and compared. Light energy conversion efficiency of DSSCs increased with decreasing in light transmittance of CNT counter electrode. Efficiency of DSSCs having CNT counter electrode is compatible to that of Pt counter electrode.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 추계학술대회 논문집
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• pp.411-414
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• 2009

Photo-capacitor electrodes are attracting great attention because of their high capacitance and potential applications in electronic devices. Carbon capacitor, active carbon capacitor and its combination will be fabricated using simple sandwich capacitor electrode method as carbonaceous material on each type of capacitor electrodes with 20 ${\times}$ 15 mm cell size. Carbon/active carbon cell was fabricated using sol-gel process with 120oC dry temperature in l hour and using sintering process with 500oC in 2 hour. The effect of sintering temperature on carbon properties was also investigated with X-ray diffraction technique to get the best sintering temperature. The detail of fabrication process will be explained. Elemental composition in electrode material can be measured using quantitative spectroscopic as and a cyclic voltammetric technique was used to study the combined effects of electrode material and effect of annealing temperature and also time on the capacitance of thermally treated in capacitor electrode. In this work, characterization impedance technique is used to measurement of capacitance and giving complementary results. Active carbon as carbonaceous material has a better capacitance in charge/discharge process with mean thickness $32{\mu}m$ and with particle size $1{\mu}m$ to $4.5{\mu}m$ in 20 ${\times}$ 15 mm sample size of capacitor electrode.