• 제목/요약/키워드: Quantitation

검색결과 626건 처리시간 0.023초

Quantitative Surface Analysis using Laser Ionisation Mass Spectrometry

  • King, Bruce V.
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 1999년도 제17회 학술발표회 논문개요집
    • /
    • pp.167-167
    • /
    • 1999
  • In laser ionisation mass spectrometry (LIMS) atoms and molecules which are desorbed from solid surfaces are ionised by an intense laser beam. The photoions which are created are then mass analysed in a time-of-flight mass spectromenter. In best situations, 10% of the ejected particles can be detected, giving the technique^g , pp b sensitivity. Since the ionisation and desorption steps are separated, matrix effects are minimised, in contrast to competitor techniques like SIMS, so quantitation is improved. The talk will illustrate the application of LIMS to basic studies in sputtering in Sr, Cu3Au(100) and Ni3Al(100) as well as ultratrace analysis of Zr in Si.

  • PDF

Proteomics 기술의 개발 및 응용 (Development and Applications of Proteomics Technology)

  • 이지원;이은규
    • KSBB Journal
    • /
    • 제16권2호
    • /
    • pp.99-106
    • /
    • 2001
  • Proteomics research includes identification and quantitation of single protein and/or protein complex, profiling of protein expression changes in response to biological perturbations, characterization of protein functions and interactions, and elucidation the linkage between proteins and diseases. In this review paper, recent developments in the basic technologies involved in the proteomics research such as 2-dimensional PAGE and mass spectrometry are discussed. Also, the application areas of proteomics technology such as protein expression mapping and cell map proteomics are introduced with the focus on new drug development.

  • PDF

Algorithm for finding the best regression models using NIR spectra

  • Cho, Jung-Hwan;Huh, Yun-Jung;Park, Young-Joo
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
    • /
    • pp.402.2-402.2
    • /
    • 2002
  • An algorithm for finding the best regression models has been developed using NIR spectral data. In cases of regression analysis for quantitation with NIR spectral data, it is very critical to find essential features from the spectral data. This task was accessed in two ways. The first one was to use all-possible combinations of varibles (wavelengths). Correlation coefficients at each spectral points were calculated to get initial set of variables and all of the possible combinations of variable sets were tested with SEC. SEP and/or $R^2$. (omitted)

  • PDF

First Derivative Spectrophotometric and Gas-Liquid Chromatographic Determination of Caffeine in Foods and Pharmaceuticals III. Simultaneous assay of caffeine and some antihistaminics

  • Abdel-Moety, Ezzat M.;El-Tarras, Mohamed F.;El-Zeany, Badr-Eldin A.;Kelani, Khadiga O.
    • Archives of Pharmacal Research
    • /
    • 제13권3호
    • /
    • pp.215-220
    • /
    • 1990
  • Two different, derivative spectrophotometric and gas-liquid chromatographic, procedures for direct quantitation of caffeine and some commonly dispensed antihistaminics in bulk forms, in their laboratory prepared mmixtures and in dosage formulations, have been investigated. The limit, sensitivity reproducibility and accuracy of each method were studied for each individual drug substance and in some usual pharmaceutical formulations.

  • PDF

산지별(産地別) 봉독액약침자극(峰毒液藥鍼刺戟)이 면역기능저하(免疫機能低下)에 미치는 영향(影響) (The Effect of Honey Bee Venom Aqua-Acupuncture by its Production from Different Regions on Decreased Immune Response)

  • 이경희;김창환;강성길;고형균
    • Journal of Acupuncture Research
    • /
    • 제17권4호
    • /
    • pp.28-40
    • /
    • 2000
  • Objectives : This study was purposed to investigate the effect of honey bee venom aqua-acupuncture on decreased immune response by its production from Korea, North America and China. Methods : ICR-mouse was exposed with four minute sublethal 60Co- $\gamma$ -ray irradiation onto the body and got a series of each country's 0.1 ml honey bee venom aqua-acupuncture to Choksamni(ST36) every other day for three times. Thereafter the numbers of WBC, delayed type hypersensitivity, hemagglutinin titers, hemolysin titers, quantitation of T-cell and B-cell, lymphocyte transformation, natural killer cell activity, interleukin-2 productivity and interferon productivity were measured. Results : The numbers of WBC, delayed type hypersensitivity, hemagglutinin titers, hemolysin titers, quantitation of T-cell and B-cell and lymphocyte transformation were increased respectively with statistical significance in Korean, North American and Chinese honey bee venom aqua-acupuncture groups as compared with the control group. The natural killer cell activity was increased with statistical significance in Korean honey bee venom aqua-acupuncture group, and Interleukin-2 productivity and interferon productivity were not shown any statistical significance in all experimental groups as compared with the control group. Conclusions : According to the results, honey bee venom aqua-acupuncture has significant effect on decreased immune response, and Korean bee venom can be substituted for North American and Chinese one.

  • PDF

Effect of Acute Heat Stress on Heat Shock Protein 70 and Its Corresponding mRNA Expression in the Heart, Liver, and Kidney of Broilers

  • Yu, Jimian;Bao, Endong
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제21권8호
    • /
    • pp.1116-1126
    • /
    • 2008
  • The objective of this study was to investigate the expression and localization of heat shock protein 70 (Hsp70) and its mRNA in the heart, liver, and kidney of acutely heat-stressed broilers at various stressing times. Male AA broilers (n = 100) were randomly divided into 5 groups of 20 birds per group. After 30 d of adaptive feeding at ambient temperature, 80 experimental broilers were suddenly heat stressed by increasing the environmental temperature from $22{\pm}1^{\circ}C$ to $37{\pm}1^{\circ}C$. The 4 groups were heat stressed for 2, 3, 5, and 10 h, respectively. The localizations of Hsp70 protein and mRNA, determined by immunohistochemical staining and in situ hybridization, respectively, were demonstrated to be tissue dependent, implying that different tissues have differential sensibilities to heat stress. Intense Hsp70 staining was identified in the vascular endothelial cell of heart, liver and kidney, suggesting an association between expression of Hsp70 in vascular endothelial cell and functional recovery of blood vessels after heat shock treatment. Ante-mortem heat stress had a significant effect on the expression of Hsp70 protein and mRNA. The quantitation of Hsp70 protein and mRNA were both time and tissue dependent. During the exposure to heat stress, the heart, liver and kidney of broiler chickens exhibited increased amounts of Hsp70 protein and mRNA. The expression of hsp70 mRNA in the heart, liver and kidney of heat-stressed broilers increased significantly and attained the highest level after a 2-h exposure to elevated temperatures. However, significant elevations in Hsp70 protein occurred after 2, 5, and 3 h of heat stressing, respectively, indicating that the stress-induced responses vary among different tissues.

식품 내 벤조피렌 분석법의 기존 연구동향 및 라만분광법 기반기술 전망 (Conventional Analytical and New Raman Spectroscopy-Based Methods for Detecting Benzo[a]pyrene in Food: Review and Perspective)

  • 이미현;이소윤;김현연;최대식;이한주;이진규
    • 한국미생물·생명공학회지
    • /
    • 제43권3호
    • /
    • pp.177-186
    • /
    • 2015
  • 국내 식품공전에 기술되어 시행중인 식품 내 벤조피렌 분석법은 회수율, 검출 및 정량 한계, 효용성과 정확성 등이 검증되어 적용되고 있다. 그러나, 기존의 시험법에는 시료의 추출 및 분리, 정제 등의 복잡한 전처리 과정이 포함되어 있다. 환경 및 식품 내 위해물질 검출법의 연구 및 개발의 현 추세는 시험비용과 시간소모를 최소화하고 시험과정을 단순화할 수 있는 비표지, 비파괴 분석법을 통해 관리 현장에서의 신속대응을 지향하고 있다. 본 총설에서는 현행의 벤조피렌 분석법에 대해 정리하고, 그 한계점을 극복하기 위한 새로운 시도로 라만 분광법을 이용한 벤조피렌 검출법에 대해 소개하고자 한다.

Simultaneous quantitative analysis of salivary cortisol and cortisone in Korean adults using LC-MS/MS

  • Lee, Sang-Hoo;Kwon, Soon-Ho;Shin, Hye-Jin;Lim, Hwan-Sub;Singh, Ravinder J.;Lee, Kyoung-Ryul;Kim, Young-Jin
    • BMB Reports
    • /
    • 제43권7호
    • /
    • pp.506-511
    • /
    • 2010
  • The levels of salivary cortisol and cortisone in Korean adults were measured for the first time using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The salivary cortisol and cortisone were separated within 10 min. The regression coefficients (r) of the calibration curves were greater than 0.999 for the two steroids. The limits of quantitation (LOQ) were 0.2 ng/ml for cortisol and 1 ng/ml for cortisone. The intra-day precisions of the assay were <3.9% and 8.6% for cortisol and cortisone respectively, and the inter-day precisions were <1.9% and 4.3% for cortisol and cortisone, respectively. The salivary cortisone concentrations were approximately 4-9 times higher than those of salivary cortisol during the daytime. Diurnal rhythms, during which the cortisol and cortisone concentrations were higher in the morning than in the afternoon, were also observed. The present assay may be useful for the diagnosis of several adrenal dysfunctions in clinical biochemistry.

HPLC를 이용한 혈중 히드로클로로티아지드의 분석 및 이를 이용한 한국인 성인남성에 대한 생체이용률 평가 (Determination of Hydrochlorothiazide in Human Plasma by HPLC and Applicability to Oral Bioavailability in Korean Healthy Male Volunteers)

  • 박아연;김진희;김성용;지상철;복혜숙;김호중;염정록;한상범
    • 약학회지
    • /
    • 제50권5호
    • /
    • pp.301-307
    • /
    • 2006
  • A simple and sensitive high-performance liquid chromatographic method for quantitation of hydrochlorothiazide in human plasma was developed and bioavailability parameters of hydrochlorothiazide were assessed in Korean healthy male volunteers. Caffeine was used as an internal standard. Hydrochlorothiazide and internal standard in plasma sample were extracted using tert-butylmethylether (TBME). A centrifuged upper layer was then evaporated and reconstituted with mobile phase of acetonitrile-25 mM phosphate buffer (20/80, pH 2.5). The reconstituted samples were injected into a Luna C18 column $(250{\times}4.6\;mm,\;5{\mu}m)$ at a flow-rate of 1.0 ml/min. The wavelength was set at 230 nm and no endogenous substances were found to interfere, A linear relationship for hydrochlorothiazide was found in the range of $10{\sim}300\;ng/ml$. The lower limit of quantitation (LLOQ) was 10 ng/ml with acceptable precision and accuracy. Assayed in plasma, the intra- and inter-day validation for all coefficients of variation (R.S.D.%) were found less than 15%. Main pharmacokinetic parameters of 50mg of hydrochlorothiazide were revealed as follows: $AUC_t\;1761{\pm}509.0\;ng{\cdot} hr\;ml,\;C_{max}\;296.5{\pm}95.5\;ng/ml,\;T_{max}\;1.94{\pm}0.85hr,\;K_{el}\;0.12{\pm}0.04\;hr^{-1}\;and T_{12}\;6.81{\pm}2.92\;hr.\;C_{max}\;and\;T_{max}$ were in accordance with the values $(270{\sim}350\;ng/ml\;and\;1.9{\sim}2.7\;hr)$ of Caucasian.