• Title/Summary/Keyword: fluorescence detector

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식물 유래 당단백질의 당질 구조 분석 (Structural Analysis of Oligosaccharides of a Plant Glycoprotein)

  • 배재우;박병태;윤두천;김주영;황혜성;박현주;나종천;김하형
    • 약학회지
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    • 제54권6호
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    • pp.449-454
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    • 2010
  • The glycosylation of glycoproteins from mammalian or plants can affect their efficacy, stability, solubility, and half-life. In the present study, we investigated plant glycosylation and their relative intensity (%) in a plant carbohydratebinding protein with the hemagglutination and antiproliferative activities. The hemagglutination activity on the deglycosylated protein was decreased as a 16-fold than that of intact glycoprotein. Using the HPLC with fluorescence detector and mass spectrometer, the major eight bi- or triantennary oligosaccharides containing xylose, fucose, mannose, galactose, and N-acetylglucosamine were identified and structurally characterized. The present results indicate that the oligosaccharides on this plant glycoprotein is necessary for their own property.

경기남부지역 원유중의 설파제 잔류조사 (Determination of Sulfonamide Residues in Raw Milk from southern Kyeonggi Area)

  • 김창수;이성권;고태오;고신일
    • 한국동물위생학회지
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    • 제19권1호
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    • pp.39-45
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    • 1996
  • Sulfonamides are widely used to treat mastitis of cattle in field. The study was carried out to analyze sulfonamid residues In raw milk from south Kyeonggi area. The milk sample was deproteinated with acetone and defatted with hexane. The residual sulfonamides were extracted with ethylacetate, concentrated under vaccum, reconstituted with the acetate buffer-methanol mixture, reacted with fluorescamine, and then analyzed by HPLC-fluorescence detector(EX. 39nm, Em. 495nm) with methanol : acetate buffer system(3/2, v /v) as a mobile phase. The results analyzed by Thin layer chromatography and High performance liquid chromatography were summarized as follows. 1. A total of 24 cases out of 478 raw milk samples(5.0%) collected during April and May showed positive reaction to sulfonamide residues. Among 24 positive reactors, 9 cases were positive to sulfanilamides(32.1%), 8 cases were positive to sulfathiazoles(28.6%) and 5 cases were positive to sulfamonomthoxines (7.9%) , respectively. 2. During July and August, 31 cases out of 464 raw milk samples(6.7%) showed positive re action to sulfonamide residues. Among them S cases were positive to sulfanilamides, 5 cases sulfathiazoles and 5 cases sulfamonomethoxines(16.1%), respectively.

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Simplified HPLC Method for the Determination of Mirtazapine in Human Plasma and Its Application to Single-dose Pharmacokinetics

  • Gwak Hye-Sun;Lee Na-Young;Chun In-Koo
    • Biomolecules & Therapeutics
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    • 제14권1호
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    • pp.40-44
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    • 2006
  • Mirtazapine is an antidepressant agent with dual action on both the noradrenergic and serotonergic neurotransmitter systems. A simple high performance liquid chromatographic method has been developed and validated for the quantitative determination of mirtazapine in human plasma. A reversed-phase Cl8 column was used for the determination of mirtazapine with a mobile phase composed of 0.01M ammonium acetate solution (pH 4.2) and acetonitrile (75:25, v/v%) at a flow rate of 1.2 mL/min. Terazosin hydrochloride was used as an internal standard. The fluorescence detector was set at excitation and emission wavelengths of 290 and 350 nm, respectively. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification of 3 ng/mL. Mirtazapine was stable in human plasma under various storage conditions. This method was used successfully for a pharmacokinetic study using plasma samples after oral administration of a single 30 mg dose as mirtazapine base to 8 healthy volunteers. The maximum plasma concentration of mirtazapine was $64.1{\pm}28.0ng/mL$ at 1.8 h, and the area under the curve and elimination half-life were calculated to be $674.1{\pm}218.5ng\;h/mL\;and\;23.4{\pm}3.8h$, respectively.

식용란의 플루오로퀴놀론계 합성항균제의 잔류에 관한 조사 (Surveys on the residual level of fluoroquinolones in eggs)

  • 고바라다;박성도;장미선;나호명;김용환
    • 한국동물위생학회지
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    • 제28권3호
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    • pp.235-243
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    • 2005
  • This surveies were carried out to investigate the residual levels of fluoroquinolones in chicken and quail eggs by bioassay and HPLC method. The eggs of 240 samples collected from market and farm in Gwangju Metropolitan city were examined from May to December in 2003. Residual antibiotic materials were detected from 47 samples of the 240 eggs by bioassay. Of the 240 eggs assayed, ciprofloxacin, danofloxacin, norfloxacin, ofloxacin, orbifloxacin and perfloxacin were not detected but enrofloxacin was detected from 5 samples in 228 chicken eggs and 1 sample in 12 quail eggs using HPLC with fluorescence detector by multi-residue method. 2 sample eggs in 6 sample which were detected by HPLC were not positive with bioassay. The average residual concentration of enrofloxacin was 0.494 mg/kg in 6 positive samples. The highest residual concentration of enrofloxacin was 1.83mg/kg.

Experimental Investigation of Clay Fly Ash Bricks for Gamma-Ray Shielding

  • Mann, Harjinder Singh;Brar, Gurdarshan Singh;Mann, Kulwinder Singh;Mudahar, Gurmel Singh
    • Nuclear Engineering and Technology
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    • 제48권5호
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    • pp.1230-1236
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    • 2016
  • This study aims to determine the effect of fly ash with a high replacing ratio of clay on the radiation shielding properties of bricks. Some interaction parameters (mass attenuation coefficients, half value layer, effective atomic number, effective electron density, and absorption efficiency) of clay fly ash bricks were measured with a NaI(Tl) detector at 661.6 keV, 1,173.2 keV, and 1,332.5 keV. For the investigation of their shielding behavior, fly ash bricks were molded using an admixture to clay. A narrow beam transmission geometry condition was used for the measurements. The measured values of these parameters were found in good agreement with the theoretical calculations. The elemental compositions of the clay fly ash bricks were analyzed by using an energy dispersive X-ray fluorescence spectrometer. At selected energies the values of the effective atomic numbers and effective electron densities showed a very modest variation with the composition of the fly ash. This seems to be due to the similarity of their elemental compositions. The obtained results were also compared with concrete, in order to study the effect of fly ash content on the radiation shielding properties of clay fly ash bricks. The clay fly ash bricks showed good shielding properties for moderate energy gamma rays. Therefore, these bricks are feasible and eco-friendly compared with traditional clay bricks used for construction.

Incidence and Level of Aflatoxins Contamination in Medicinal Plants in Korea

  • Lee, Sung Deuk;Yu, In Sil;Jung, Kweon;Kim, Yeon Sun
    • Mycobiology
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    • 제42권4호
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    • pp.339-345
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    • 2014
  • During 2011~2013, a total of 729 samples for 19 types of medicinal plant were collected from Seoulyekryungsi in Seoul, Korea, and investigated for the presence of aflatoxins. The samples were analyzed using immunoaffinity column cleanup and high-performance liquid chromatography coupled to a fluorescence detector after post-column derivatization. Aflatoxins were found in 124 out of the 729 analyzed samples: 65 containing aflatoxin B1 (AFB1), 24 with aflatoxin B2 (AFB2), 15 with aflatoxin G1 (AFG1), and 20 samples with aflatoxin G2 (AFG2). The ranges for positive samples were $0.1{\sim}404.7{\mu}g/kg$ for AFB1, $0.1{\sim}10.0{\mu}g/kg$ for AFB2, $0.1{\sim}635.3{\mu}g/kg$ for AFG1, $0.1{\sim}182.5{\mu}g/kg$ for AFG2, and $0.1{\sim}1,043.9{\mu}g/kg$ for total aflatoxins. Most of the medicinal plant samples (721, 98.9%) were below legal limits, but 8 samples exceeded the legal limits of 10 and $15{\mu}g/kg$ established by the Korean standard for AFB1 and total aflatoxins (the sum of AFB1, AFB2, AFG1 and AFG2), respectively.

FMOC 표식에 의한 Sugar Chain의 분석 (Application of FMOC-Cl for the Quantitative Determination of N-linked Oligosaccharides)

  • 김동현;황보식;정구용
    • 한국식품과학회지
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    • 제29권4호
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    • pp.630-634
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    • 1997
  • N-glycanase처리에 의해 얻어진 1-amino-oligosaccharide를 FMOC-Cl로 표식 하는 방법을 확립하였다. 이 방법에 의해 얻어진 FMOC-표식 oligosaccharides는 기존의 방법보다 약 4배의 감도를 나타내었다. Amido 80 column을 사용한 분석에 의하여, Man 5-9 GlcNAc 2 amines의 5개의 성분은 각각 분리되어 용출 되었으며, 회수율은 기존의 방법과 거의 같았다. 1-amino-oligosaccharides는 0.05 pmol에서 1.5 pmol 사이에서 직선적인 관계를 나타내었으며, 2-aminopyridine에 의한 표식과 비교하였을 때, 안정된 화합물을 형성하고 있으며, 감도가 높아 미량의 oligosaccharides의 분석에 매우 적합한 것이 확인되었다.

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Fluorimetric Determination of Dichloroacetamide by RPLC with Postcolumn Detection

  • Choi, Yong-Wook;Reckhow, David A.
    • Bulletin of the Korean Chemical Society
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    • 제25권6호
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    • pp.900-906
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    • 2004
  • An RPLC-postcolumn detection method has been developed for the fluorimetric determination of dichloroacetamide (DCAD) in water. After ammonia and DCAD were separated on a $C_{18}$ nonpolar stationary phase with 2.5% methanol-0.02 M phosphate buffer at pH 3, the column eluant was reacted with post column reagents, o-phthaldialdehyde (OPA) and sulfite ion at pH 11.5, to produce a highly fluorescent isoindole fluorophore, which was measured with a fluorescence detector ( ${\lambda}_{ex}$ = 363 nm, ${\lambda}_{em}$ = 425 nm). With the optimized conditions for RPLC and the postcolumn derivatization, the calibration curve was found to be linear in the concentration ranges of 0.5 and 20 ${\mu}$M for DCAD, and the detection limit for DCAD was 0.18 ${\mu}$M (23${\mu}$g/L). This corresponded to 18 pmol per 100 ${\mu}$L injection volume for a signal-to-noise ratio of 3, and the repeatability and reproducibility of this method were 1.0% and 2.5% for five replicate analyzes of 2 ${\mu}$M DCAD, respectively. The degradation yields DCAD to ammonia were 94 and 99%, and the percent recoveries of DCAD from 4 and 6 ${\mu}$M DCAD-spiked tap water were shown mean more than 97%.

Capillary Gel Electrophoretic Analysis of Cattle Breeds Based on Difference of DNA Mobility of Microsatellite Markers

  • Lee, Mi-Ji;Yoon, Du-Hak;Jeon, Jin-Tae;Eo, Seong-Kug;Kang, Seong-Ho
    • Bulletin of the Korean Chemical Society
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    • 제30권11호
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    • pp.2655-2660
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    • 2009
  • A breed of cattle, i.e., Korean cattle (Hanwoo), was identified based on the DNA mobilities of their microsatellites (MSs) by capillary gel electrophoresis (CGE) with a laser-induced fluorescence (LIF) detector. The MS markers were used for the accurate identification of species-specific genes. The DNA mobilities of the MS markers of Hanwoo and Holstein were measured using a CGE system with a fused-silica capillary (inner diameter of 75 ${\mu}m$, outer diameter of 365 ${\mu}m$, and total length of 50 cm). The capillary was dynamically coated with 1.0% (w/v) polyvinylpyrrolidone ($M_r$ = 1,000,000) and then filled with a mixture of 1.3% (w/v) poly(ethylene oxide) ($M_r$ = 600,000) and 1.9% (w/v) poly(ethylene oxide) (Mr = 8,000,000) as a sieving gel matrix. The species-specific genes of Hanwoo and Holstein were clearly distinguished within 33 min. This CGE assay technique is expected to be a useful analytical method for the fast and accurate identification of breeds of cattle.

초고에너지 우주선 관측을 위한 JEM-EUSO 프로젝트의 진행 현황

  • 임희진;김석환;김순욱;박일흥;양종만;이직;정애라
    • 천문학회보
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    • 제37권2호
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    • pp.222.1-222.1
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    • 2012
  • JEM-EUSO (Extreme Universe Space Observatory on-board the Japanese Experiment Module)는 국제우주정거장(International Space Station)의 일본 실험 모듈인 'KIBO'에 우주 망원경을 설치하여, 100 EeV이상의 초고에너지 우주선 관측을 수행함으로써, 초고에너지의 스펙트럼, 구성성분과 기원을 연구하는 국제공동연구 프로젝트이다. 구경 2.5 m로 60도의 광시야각을 가지는 대형 굴절 망원경을 통해서, 지구 대기에 우주선 shower로부터 발생한 형광 신호를 관측하려고 한다. 이 프로젝트는 2016~2017년에 발사되어, 5년 이상의 임무 수행을 목표로 하고 있으며, 그 전단계로 Prototype 시스템을 가지고 지상실험인 EUSO-TA와 고도 40 km에서 수행할 EUSO-Balloon실험을 준비하고 있다. 먼저, 망원경의 prototype을 2012년 12월쯤 미국 유타에 있는 Telescope Array(TA) 실험에 설치하여 우주선 또는 임의로 인가한 광원에 의해서 생성된 shower를 TA의 Fluorescence Detector와 함께 측정하여, 시스템 calibration과 더불어 지상에 검출된 우주선을 연구할 계획이다. 그 이듬해인 2013년 여름에는 Balloon에 망원경의 Engineering model을 실어서, 대기고도 40 km아래에서 우주선에 의해 생성되는 shower를 개발한 트리거 시스템을 통해서 검출하고, 대기권에 존재하는 UV background 광원들을 측정하여 우주선을 연구할 예정이다. 한국 그룹은 JEM-EUSO을 위해서 개발한 디지털 신호처리 및 트리거 장치의 제작 중에 있으며, 위의 실험들을 위해 망원경과 함께 조립하여 테스트를 수행할 계획이다.

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