• 대한화학회지
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• 제41권5호
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• pp.246-250
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• 1997

히드록실아민이 존재하는 붕산염 매질에서 루테늄(III)은 수은 표면에 사전농축이 잘 되었고 이 피흡착질의 환원 생성물에 의한 촉매 수소 전류를 측정함으로써 혼적량 루테늄을 정량할 수 있었다. 순환 전압전류법으로 산화환원 및 흡착 누적 특성을 조사하였다. 최적 조건은 다음과 같다: 붕산염 0.015 M, pH 2,5, 히드록실아민 0.55 M, 누적 전위 -0.70 V, 그리고 시차 펄스 모드에서 주사속도 5 mV/s이었다. 이 조건에서 검출한계는 $3{\times}10^{-10}$(7분 수집)이었다. 방해 가능한 다른 백금족 금속이온들의 허용량도 조사하였다.

• Environmental Analysis Health and Toxicology
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• 제20권4호통권51호
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• pp.333-341
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• 2005

In order to know whether polychaetes could be used as an appropriate organism for the detection of genotoxicity, DNA strand breaks were evaluated in blood cells of a nereidae worm (Perinereis aibuhitensis) exposed to various aquatic chemical pollutants (e.g. Cd, Pb, Pyrene, Benaor[a]pyrene). Hydrogen peroxide increased DNA strand breaks up to the highest concentration (10 $\mu$M). Higher concentration than 0.1 $\mu$M showed a significantly more DNA damage than control. Cadmium and lead also showed higher DNA damage than control, over 1.0 and 1 $\mu$g/L, respectively. In case of pyrene, DNA damage was detected even at 0.001 $\mu$g/L. However, DNA damage decreased due to apoptosis at the highest concentration of pyrene and Pb. This study suggested that the polythaetous blood cells could be used effectively for screening genotoxic contaminants in the environment.

• 센서학회지
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• 제15권5호
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• pp.317-322
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• 2006

A method to determine quinine in aqueous solution by chemiluminescence method using a stopped flow system has been studied. The method is based on the increased chemiluminescence intensity with the addition of quinine to a solution of lucigenin and hydrogen peroxide. The effects of KOH concentration, flow rate of reagents, $H_{2}O_{2}$ concentration used for the masking of quinine on the chemiluminescence intensity have been investigated. The calibration curve for quinine was linear over the range from $1.0{\times}10^{-7}$ M to $1.0{\times}10^{-3}$ M, coefficient of correlation was 0.993 and the detection limit was $3.0{\times}10^{-8}$ M under the optimal experimental conditions of 1.0 M, 1.5 M, 3.0 mL/min for the concentration of $H_{2}O_{2}$, KOH and flow rate of reagents, respectively.

• 한국대기환경학회지
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• 제21권6호
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• pp.593-603
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• 2005

Passive sampler using 4-amino-3-hydrazino-5-mercapto-1, 2, 4-triazole (AHMT) was developed to determine formaldehyde in indoor environment. The chromatography paper cleaned by $3\%$ hydrogen peroxide solution was experimently determined as a optimum absorbtion filter for the collection of formaldehyde. The passive sampler with a broad cross-sectional area and a short diffusion length was quite good in sensitivity. The passive sampler and the active sampling method with an impinger were strongly correlated with a correlation coefficient of 0.9848. The limits of detection and quantification of the passive sampler for the measurement of formaldehyde in the indoor environment were 7.5 and 10.2 ppb, respectively. Temperature ($19\∼28^{circ}C$) and relative humidity ($30\∼90\%$) had slight influence on the sampling rate of the passive sampler. However, the increase of flow velocity on the surface of sampler resulted in the increase of sampling rate.

• 분석과학
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• 제7권3호
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• pp.349-359
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• 1994

천연가스 중의 부취제 농도를 분석하기 위한 기체 크로마토그래피 방법에 대하여 연구하였다. TBM(tertiarybutylmercaptan) 및 THT(tetrahydrothiophene)를 포함한 8종의 부취제를 OV-101 컬럼상에서 거의 완전히 분리하였다. 수소 유속, 공기 유속 및 검출기 온도와 같이 FPD의 응답에 영향을 미치는 몇 가지 상호 관련된 파라미터들의 최적 조건을 구하였다. TBM과 THT의 검정곡선을 투과한 장치를 이용하여 작성하였다. 이러한 분석방법을 천연가스 공급관 내의 혼합 부취제인 TBM과 THT를 정량하는 데 적용하였다. 부취수준과 부취제 농도와의 상관관계를 구하기 위한 냄새 측정기의 유용성에 대하여 알아보았다.

• 천문학회보
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• 제41권2호
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• pp.55.3-55.3
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• 2016

By comparing MIRIS Paschen-${\alpha}$ ($Pa{\alpha}$) Galactic Plane Survey (MIPAPS) data with Anderson's H II region catalog (the most complete Galactic H II region catalog up to date), we confirmed $Pa{\alpha}$ detections from ~50% of the H II region candidates in Cepheus (Galactic longitude from $+96^{\circ}$ to $116^{\circ}$). The detection of the hydrogen recombination line identifies these candidates as clear H II regions. If we extend this result to the whole plane, more than 1000 candidates are expected to be identified as H II regions. In this contribution, we present the results of quantitative estimations (brightness, size, etc.) for the $Pa{\alpha}$ blobs detected in Cepheus. To obtain intensity of $Pa{\alpha}$ emission line, we perform background and point spread function (PSF) matching between two filter images (line and continuum filters) as well as flux calibration.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4171-4175
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• 2011

Bio-functionalized gold nanoparticles (AuNPs), which bio-specifically interact with biotin-(strept)avidin, were investigated in this study. AuNPs were functionalized with a synthetically-provided biotin-linked thiol (BLT), which was synthesized by amidation of the active ester of biotin with 2-mercaptoethylamine. The BLT-attached AuNP was bio-specific for streptavidin, making it potentially useful for biosensor applications. To test the bio-specific interactions, the colors, absorption spectra and TEM images were investigated for proteins such as streptavidin, cytochrome C, myoglobin and hemoglobin. The colors and absorption spectra changed when streptavidin was added to the BLT-attached AuNP solution. However, the color and spectra did not change when the other proteins were added to the same solution. These results show that the AuNPs provided a colloidal solution with excellent stability and highly selective absorption characteristics for streptavidin as a target molecule. Proteins were also screened in order to identify a general strategy for the use of optical biosensing proteins based on AuNPs. In addition, TEM images confirmed that streptavidin led the BLT-attached AuNPs to aggregate or precipitate.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2423-2430
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• 2014

Nitrogen-doped short tubular carbons (N-STCs) with big inner diameter have been successfully synthesized via carbonization of polydopamine (PDA) wrapped halloysite nanotubes (HNTs). The obtained N-STCs have average length of $0.3{\mu}m$ with big inner diameter (50 nm), thin wall (2-3 nm) and large surface area ($776m^2g^{-1}$), and show excellent electrochemical properties. As an example in electrochemical applications, N-STCs were used to electrochemically detect hydrogen peroxide ($H_2O_2$) and glucose. The results showed that the N-STCs modified glassy carbon (N-STCs/GC) electrode had much better analytical performance (lower detection limit and wider linear range) compared to the acid-treated carbon nanotubes (AO-CNTs) based GC electrode. The unique structure endows N-STCs the enhanced electrochemical performance and promising applications in electrochemical sensing.

• Mass Spectrometry Letters
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• 제3권3호
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• pp.78-81
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• 2012

The hydrophobic hydrocarbon chain and the polar sulfate group confer surfactant properties and enable them to be used as anionic surfactants. Anionic surfactants (AS) are known for their adverse impact on environment, particularly on aquatic ecosystem. In the present study a fast, sensitive and selective method for the determination and subsequent quantification of six anionic surfactants was developed using hydrophilic interactive liquid chromatography (HILIC) coupled to a electrospray ionization (ESI) mass spectrometer (MS), in the concentration range 15-20 ${\mu}g/L$. The capability of the method was established using regression analysis and ANOVA. The method performance was evaluated by analyzing real time surface water spiked with 1-dodecyl hydrogen sulfate at 15 ${\mu}g/L$. Combined efficiency of solid phase extraction and MS detection established recovery of 89% in presence of natural matrix. These results point out that HILIC coupled to multistage MS procedures can be a powerful technique for environmental applications concerning the screening of polar contaminants.

• Biomolecules & Therapeutics
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• 제21권1호
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• pp.1-9
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• 2013

Polyamines, putrescine, spermidine and spermine, are ubiquitous in living cells and are essential for eukaryotic cell growth. These polycations interact with negatively charged molecules such as DNA, RNA, acidic proteins and phospholipids and modulate various cellular functions including macromolecular synthesis. Dysregulation of the polyamine pathway leads to pathological conditions including cancer, inflammation, stroke, renal failure and diabetes. Increase in polyamines and polyamine synthesis enzymes is often associated with tumor growth, and urinary and plasma contents of polyamines and their metabolites have been investigated as diagnostic markers for cancers. Of these, diacetylated derivatives of spermidine and spermine are elevated in the urine of cancer patients and present potential markers for early detection. Enhanced catabolism of cellular polyamines by polyamine oxidases (PAO), spermine oxidase (SMO) or acetylpolyamine oxidase (AcPAO), increases cellular oxidative stress and generates hydrogen peroxide and a reactive toxic metabolite, acrolein, which covalently incorporates into lysine residues of cellular proteins. Levels of protein-conjuagated acrolein (PC-Acro) and polyamine oxidizing enzymes were increased in the locus of brain infarction and in plasma in a mouse model of stroke and also in the plasma of stroke patients. When the combined measurements of PC-Acro, interleukin 6 (IL-6), and C-reactive protein (CRP) were evaluated, even silent brain infarction (SBI) was detected with high sensitivity and specificity. Considering that there are no reliable biochemical markers for early stage of stroke, PC-Acro and PAOs present promising markers. Thus the polyamine metabolites in plasma or urine provide useful tools in early diagnosis of cancer and stroke.