• Title/Summary/Keyword: electrospray

Search Result 439, Processing Time 0.029 seconds

Determination of Enalapril in Human Plasma by High Performance Liquid Chromatography-Electrospray Ionization Mass Spectrometry

  • Yoon, Kyung-Hwan;Kim, Won;Park, Jong-Sei;Kim, Hie-Joon
    • Bulletin of the Korean Chemical Society
    • /
    • v.25 no.6
    • /
    • pp.878-880
    • /
    • 2004
  • Revered-phase LC-electrospray ionization mass spectrometry was used to selectively determine enalapril from plasma with minimal sample preparation. Detection limit of the method was 1 ng/mL. Precision (within day and between days) and accuracy of the method at various concentrations were acceptable. The analytical technique was used for pharmacokinetic studies after administration of enalapril to human test subjects.

Comparison of Antibacterial Ability of Air Filter Media Treated with a Natural Antibacterial Agent by Three Treatment Methods (항균성 천연물질의 도포방법에 따른 에어필터 여재의 항균 특성 비교)

  • Park, Sun Young;Jung, Jae Hee;Hwang, Gi Byung;Bae, Gwi-Nam;Kim, Yong Pyo;Nho, Chu Won
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.29 no.2
    • /
    • pp.125-134
    • /
    • 2013
  • Various antimicrobial technologies have been developed to inactivate bioaerosols in indoor environments. In this study, air filter media were treated with a natural antibacterial agent of Sophora flavescens in order to inactivate the bacteria collected on the air filter. Three treatment methods were applied to manufacture the test antibacterial air filter media: electrospray, nebulization and dip-coating methods. In case of electrospray and nebulization processes, the size distribution of aerosolized natural antibacterial agent was measured using a scanning mobility particle sizer. Staphylococcus epidermidis bacteria were aerosolized to test inactivation of the filter media treated with a natural antibacterial agent. The pressure drop and the antibacterial efficiency of the filter media increased with increasing the mass loading of natural antibacterial agent in each treatment method. The antibacterial efficiency per loaded antibacterial agent mass by the electrospray method was the highest and the filter treated by the dip-coating method was the lowest among three treatment methods.

Focused Electrospray Deposition for Matrix-assisted Laser Desorption/Ionization Mass Spectrometry

  • Jeong, Kyung-Hwan;Seo, Jong-Cheol;Yoon, Hye-Joo;Shin, Seung-Koo
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.8
    • /
    • pp.2293-2298
    • /
    • 2010
  • Focused electrospray (FES) deposition method is presented for matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. FES ion optics consists of two cylindrical focusing electrodes capped with a truncated conical electrode through which an electrospray emitter passes along the cylindrical axis. A spray of charged droplets is focused onto a sample well on a MALDI target plate under atmospheric pressure. The shape and size distributions of matrix crystals are visualized by scanning electron microscope and the mass spectra are obtained by time-of-flight mass spectrometry. Angiotensin II, bradykinin, and substance P are used as test samples, while $\alpha$-cyano-4-hydroxycinnamic acid and dihydroxybenzoic acid are employed as matrices. FES of a sample/matrix mixture produces fine crystal grains on a 1-3 mm spot and reproducibly yields the mass spectra with little shot-to-shot and spot-to-spot variations. Although FES greatly stabilizes the signals, the space charge due to matrix ions limits the detection sensitivity of peptides. To avoid the space charge problem, we adopted a dual FES/FES mode, which separately deposits matrix and sample by FES in sequence. The dual FES/FES mode reaches the detection sensitivity of 0.88 amol, enabling ultrasensitive of peptides by homogeneously depositing matrix and sample under atmospheric pressure.

Effective Dispersion of Electrode Catalysts for Direct Formic Acid Fuel Cells by Electrospray Method (정전분무법을 이용한 직접개미산 연료전지 전극촉매의 효율적인 분산)

  • Kwon, Byeong-Wan;Kim, Jin-Soo;Kwon, Yong-Chai;Han, Jong-Hee
    • Journal of the Korean Electrochemical Society
    • /
    • v.11 no.4
    • /
    • pp.262-267
    • /
    • 2008
  • Effective dispersion of noble metal Pt-Ru catalysts was conducted for the application of direct formic acid fuel cell(DFAFC) electrodes by electrospray method. The amount of catalysts deposited on the electrodes increased with increasing deposition time. However, the performance of cell test decreased with the deposition time after 80 min. because of agglomeration of catalysts. With the conventional hand-spray method, the density of the anode catalysts deposited was $3.0\;mg/cm^2$ and the maximum power density of the MEA was $74\;mW/cm^2$. On the other hand, the MEA prepared by the electrospray method, showed a similar power density of $72\;mW/cm^2$. However, the density of the anode catalysts deposited was much lower than the case of the hand-spray and the density the anode catalysts in this case was $1.85\;mg/cm^2$.

Electrospray Tandem Mass Spectrometry for the Quantification and Bioavailability Test of Gliquidone in Human Plasma (Electrospray Tandem Mass를 이용한 혈중 글리퀴돈의 정량법 개발 및 생체이용률시험)

  • Moon Chul-Jin;Lee Eun-Hee;Yang Song-Hyun;Moon Hae-Ran
    • YAKHAK HOEJI
    • /
    • v.49 no.3
    • /
    • pp.212-216
    • /
    • 2005
  • A rapid, sensitive and selective electrospray tandem mass spectrometric (ESI-LC/MS/MS) method for the quantitation of gliquidone in human plasma was developed. A bioavailability study of gliquidone tablet (30 mg gliquidone, Boehringer Ingelheim Korea Co.) was performed using the validated ESI-LC/MS/MS method. The dose of 30 mg of gliquidone (1 tablet) was orally administered to 9 healthy Korean subjects. After administration, blood was taken at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 7, 9, 12, 24, and 33 hour. The validation data were as follows; the standard curve was linear ($r^2$=0.999) over the concentration range of $10\~1000 ng/ml$. The coefficient of variation for intra- and inter-day assay were $8.30\~18.86$, and $2.19\~12.92\%$, respectively. The lower limit of quantification for gliquidone was 10 ng/ml. The pharmacokinetic parameters obtained were as follows; $AUC_t$ was 3861.17$\pm$1328.61 ng-hr/ml, $C_{max}$ was 831.02$\pm$227.99 ng/ml, $T_{max}$ was $2.94{\pm}0.77 hr,\;K_e$, was 0.19$\pm$0.06 1/hr, and $t_{l/2}$ was 4.47$\pm$3.52 hr. Based on the validated analytical method and pharmacokinetic parameters, a standard guideline of the bioavailability test of gliquidone dosage forms was prepared successfully and could be used for the bioequivalence test of gliquidone preparation.

Biodegradable PLGA Polymer Coating on Biomedical Metal Implants Using Electrospraying (전기분사를 이용한 의료용 금속 임플란트의 생분해성 PLGA 고분자 코팅)

  • Cho, Seong-Bae;Park, Chul-Ho;Park, Kwi-Deok;Chung, Dong-Jun;Han, Dong-Keun
    • Polymer(Korea)
    • /
    • v.33 no.6
    • /
    • pp.620-624
    • /
    • 2009
  • Biomedical metal implants have been used clinically for replacement, restoration, or improvement of injury bodies based on high mechanical properties, but it has some risks such as the inflammatory, late thrombosis, or restenosis due to the low biocompatibility and toxicity. In various techniques of surface treatment developed to preserve these drawbacks, this study examined the electrospray coating technology with biodegradable poly (lactic-co-glycoic acid) (PLGA) on metal surface. Based on fundamental examination of electrospraying and solution parameters, the surface morphology of coated film was closely related to the boiling point of solvent, in-flight distance, and droplet size. The thickness of polymer film was linearly proportional to the emerged volume. This result exhibits that the polymeric droplets were continuously deposited on the polymer film. Therefore, the electrospray coating technology might be applied into the fabrication of single/multi-layered polymer film in nano-/micro-thickness and the control of the topology for biomedical metal implants including stents.

A Study on High performance Electrical Precipitation Technology for PM Removal in Exhaust Gas (배가스 내 미세먼지 제거를 위한 고성능 집진 기술에 대한 연구)

  • Kim, Soyeon;Kim, Minsung;Choi, Sangmi;Jung, Minkyu;Lee, Jinwook
    • Plant Journal
    • /
    • v.18 no.1
    • /
    • pp.50-54
    • /
    • 2022
  • The demand for high-efficiency dust collectors is rapidly increasing to remove PM from exhaust gas emission facilities, such as thermal power plants, steel mills, and industrial cogeneration plants, as the Pmemission standards have been strengthened. In this study, the electrospray is adapted for existing electrosratic precipitator(EP) to remedy its shortcomings and to improve the performance. Electrospray has been mainly used for the purpose of generating very fine droplets, but fir the purpose of EP, the flow rate over 10 mL/min per nozzleis required, and a high flow rate condition of 65 to 200 times is required. The electrospray of high flow rate has a completely different spray shape from the low flow rate condition, and was visualized through various figures such as corona discharge photographs and shadow images.

  • PDF

Preparation of Crack-free ZIF-7 Thin Films by Electrospray Deposition (정전분무법에 의한 결함없는 ZIF-7 박막의 제조)

  • Melgar, Victor Manuel Aceituno;Kim, Jinsoo
    • Membrane Journal
    • /
    • v.23 no.4
    • /
    • pp.278-282
    • /
    • 2013
  • Zeolitic imidazolate frameworks (ZIFs) have been the focus of interest for their physical and chemical properties, especially, for their extraordinary gas separation properties. In this study, a novel and efficient method for the fabrication of continuous ZIF-7 film on ${\alpha}$-alumina substrate has been investigated. The electrospray deposition method was tried for the first time to prepare ZIF films directly without the necessity of prior substrate seeding. It has the advantage of depositing thin ZIF-7 films directly on the ${\alpha}$-alumina substrate by electrospraying the precursor solution. The ZIF-7 films have been characterized through XRD, FE-SEM, and single gas permeation tests.

A study on the characteristics of $TiO_2$ electrode in dye-sensitized solar cells using electrospray method (정전분무법을 이용한 염료감응형 태양전지의 $TiO_2$ 박막 특성에 관한 연구)

  • Jang, Jin-Ju;Hong, Ji-Tae;Lee, Dong-Gil;Lee, Kyoung-Jun;Son, Min-Gu;Kim, Jin-Kyung;Kim, Hee-Je
    • Proceedings of the KIEE Conference
    • /
    • 2009.07a
    • /
    • pp.1423_1424
    • /
    • 2009
  • Dye sensitized solar cells(DSC) have been very economical and easy method to convert solar energy to electricity. DSC can reach low costs in future outdoor power applications. However, to commercialize the DSC, there are still many shortages to overcome such as a low efficiency in a large size DSC. In this study, DSCs were fabricated by an electrospray coating method for the $TiO_2$ thin film. They were compared with DSCs prepared by conventional coating methods. We conducted an experiment to obtain the optimized parameters of voltage, flow rate, incident angle and distance in the electrospray method. After we manufactured $TiO_2$ film using that way, we could analyze the characteristics of DSC through SEM, UV curve, EIS.

  • PDF