• Title/Summary/Keyword: Gd-complex

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Preparation of Metal-p-aminobenzyl-DOTA Complex Using Magnetic Particles for Bio-tagging in Laser Ablation ICP-MS

  • Yoon, S.Y.;Lim, H.B.
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3665-3670
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    • 2012
  • Metal-p-$NH_2$-Bn-DOTA (paraammionobenzyl-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid: ABDOTA) complex was synthesized and purified for bio-tagging to quantify biological target materials using laser ablation (LA)-ICP-MS. Since the preparation of a pure and stable tagging complex is the key procedure for quantification, magnetic particles were used to purify the synthesized metal-ABDOTA complex. The magnetic particles immobilized with the complex attracted to a permanent magnet, resulting in fast separation from free un-reacted metal ions in solution. Gd ions formed the metal-complex with a higher yield of 64.3% (${\pm}3.9%$ relative standard deviation (RSD)) than Y ions, 52.3% (${\pm}2.5%$ RSD), in the pH range 4-7. The complex bound to the magnetic particles was released by treatment with a strong base, of which the recovery was 81.7%. As a reference, a solid phase extraction (SPE) column packed with Chelex-100 resin was employed for separation under similar conditions and produced comparable results. The tagging technique complemented polydimethylsiloxane (PDMS) microarray chip sampling in LA-ICP-MS, allowing determination of small sample volumes at high throughputs. For application, immunoglobulin G (IgG) was immobilized on the pillars of PDMS microarray chips and then tagged with the prepared Gd complex. IgG could then be determined through measurement of Gd by LA-ICP-MS. A detection limit of 1.61 ng/mL (${\pm}0.75%$ RSD) for Gd was obtained.

Gadolinium Complex of 1,4,7,10-Tetraazacyclododecane-1,4,7-trisacetic acid (DO3A) Conjugate of [(p-aniline benzothiazole)methyl]pyridine as a Tumor-Targeting MRI Contrast Agent

  • Nam, Ki Soo;Jung, Ki-Hye;Chang, Yongmin;Kim, Tae-Jeong
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3654-3658
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    • 2013
  • The synthesis of a DO3A conjugate of [(p-aniline benzothiazole)methyl]pyridine ($L^2H_3$) and its gadolinium complex of the type [$Gd(L^2)(H_2O)$] ($GdL^2$) is described. The $R_1$ relaxivity ($=4.50mM^{-1}sec^{-1}$) and kinetic inertness of $GdL^2$ compares well with those of structurally analogous Dotarem$^{(R)}$ ($R_1=3.70mM^{-1}sec^{-1}$), a typical extracellular (ECF) MRI contrast agent (CA). Yet, by comparison with Dotarem$^{(R)}$, $GdL^2$ exhibits non-covalent interactions with human serum albumin (HSA) as evidenced by the ${\varepsilon}^*$ titration curve along with in vivo MR signal enhancement in both aorta and heart. Liver-specific nature of $GdL^2$ is also observed as excretion is made through gallbladder. Most notably, $GdL^2$ further demonstrates specificity toward the MDA-MB-231 breast cancer.

Effect of Rare Earth (Gd, Er) on the Permeabilities of Ba-Ferrite (회토류(Gd, Er)첨가가 Ba 페라이트의 투자율에 미치는 영향)

  • 정승우;김태원;최우성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.10
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    • pp.887-894
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    • 2000
  • In this paper, we have studied the effect of earth (Gd, Er) on the various properties (microstructure, shrinkage, initial permeability, permeability as a function of frequency, etc) of Ba-ferrite. The permeabilities were analyzed by Impedance Analyzer(100KHz~40MHz) and Network Analyzer(30KHz~3㎓). As the result of XRD, all of the Ba-ferrite doped with rat earth was found to be Y-hexagonal phase. The resonance frequencies at the maximum imaginary value of complex permeability were observed near 2㎓. The complex permeabilities of the Ba-ferrite doped with Gd$_2$O$_3$at 3wt% and doped with Er$_2$O$_3$at 3wt% and 5wt% as a function of frequency showed the highest value at sintered temperature at 95$0^{\circ}C$/3h.

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Study on Development of Herbal Feed Supplement for Ducks

  • Seo, Min-Jun;Lee, Jong-Hyun;Jin, Jong-Sik;Park, Jin-Han;Lee, Jun-Ho
    • Journal of Evidence-Based Herbal Medicine
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    • v.2 no.1
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    • pp.19-24
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    • 2009
  • GD68 is newly developed herb complex prescription. The constituent herbs of GD68 were Massa Medicata Fermentata, Atractylodis Rhizoma Alba, Poria, Zingiberis Siccatum Rhizoma, Crataegi Fructus, Saccarum Granorum, Agastachis Herba, Taraxaci Herba, Perillae Herba, Scutellariae Radix, Astragali Radix, Ginseng Radix, Houttuyniae Herba and Halloysitum Rubrum. The aim of this study was to examine feed value of GD68 in duck. The weight gain of ducks fed with supplemental GD68 high compared to those of the control. The feed intake and mortality of ducks fed with supplemental GD68 low compared to those of the control. The moisture, crude lipid and calorie content of the ducks fed GD68 were decreased, but the crude protein content of the ducks fed GD68 was increased. And we investigated the effect of GD68 on the production of cytokines in human T-cell line, MOLT-4 cells. GD68 plus concanavalin A (Con A) increased the interferon-$\gamma$ and interleukin-2 production compared with Con A alone. These results indicate that the supplemental GD68 may improve the production, meat quality and immunity of ducks.

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A Survey on Korean Medicine Doctors' Recognition for Developing Korean Medicine Clinical Practice Guideline for Growth Disorders (성장장애 한의표준임상진료지침 개발을 위한 한의사 인식조사)

  • Ahn, Hye Ri;Sim, Soo bo;Lee, Hye Lim
    • The Journal of Pediatrics of Korean Medicine
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    • v.35 no.4
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    • pp.1-15
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    • 2021
  • Objectives The purpose of this study is to provide data for development of the korean medicine (KM) clinical practice guidelines (CPG) for growth disorder (GD) by identifying the awareness and knowledge needs of KM doctors (KMD) through online survey. Methods Survey questionnaire was produced by referring to the previous recognition survey studies for clinical KMDs. The survey questionnaire was composed 18 questions regarding the current status of clinical care for GD, clinician's knowledge level about GD, and other details that clinicians use during practice. The survey was conducted from January 2021 to March 2021. An online survey was conducted on 101 KMDs from the association of pediatrics of KM. Results According to the survey, 96 respondents (40.3%) said the causation of GD without growth hormone deficiency needs to be included in CPG. 96 (23.5%) of the respondents wishes to utilize percentile in diagnosis and evaluation of the growth assessment. 24.7% of the clinicians were using the herbal medicine treatment. Currently, when treating with KM for GD, herbal medicine (100%) is the most widely used, followed by acupuncture (77.6%), and moxibustion (36.7%). In terms of a complex treatment, growth therapy efficacy (26.8%) is shown to be the most important factor to consider and needed to be included in CPG for the complex treatment, and diet (22.3%) is also considered to be important in GD. Conclusions In this study, we were able to understand the clinical KMDs' perception of GD, knowledge level, and the requirements in the CPG. The results of this study will provide the basic data for development of CPG for GD.

Screening of Eu3+-and Tb3+-Activated Phosphors for PDP in the System of CaO-Gd2O3-Al2O3 (CaO-Gd2O3-Al2O3계에서의 PDP용 Eu3+와 Tb3+ 활성 형광체의 탐색)

  • Park, Sang-Mi;Kim, Chang-Hae;Park, Hui-Dong;Jang, Ho-Gyeom;Park, Jun-Taek
    • Journal of the Korean Chemical Society
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    • v.46 no.4
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    • pp.336-345
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    • 2002
  • In this study, we have screened $Eu^{3+}$- and $Tb^{3+}$-activated candidate phosphors for PDP in the sys-tems of CaO-Gd$_2$O$_3$-Al$_2$O$_3$ by combinatorial chemistry and investigated the synthetic temperature, optimum com-position and luminescent properties about the candidate phosphors. To construct the emission intensity library by VUV PL, we have synthesized 210 different compositional samples using a polymerized-complex method. Good luminescent samples were identified by X-ray diffraction method. $Ca_$\alpha$$G$d_{0.95-$\alpha$-$\beta$}Al_$\beta$O_$\delta$$ : Eu(0.02< $\alpha$+$\beta$ <0.04) phos-phors screened as a red phosphor have good color purity than commercial phosphor. In the candidate phosphors of CaGdAl$_3O_7$ : Tb, Ca$Al_{12}O_{19}$ : Tb, Gd$_4$Al$_2O_9$ : Tb, and Gd$_3Al_5O_{12}$ : Tb CaGdAl$_3O_7$ : Tb, and Ca$Al_{12}O_{19}$ : Tb have shorter decay time than commercial phosphor.

Pharmacokinetics and Bio-distribution of New Gd-complexes of DTPA-bis (amide) (L3) in a Rat Model (쥐를 이용한 새로운 가돌리늄 조영제 Gd-DTPA-bis(amide)(L3)의 약동학 및 생체내 분포 특성에 대한 연구)

  • Yan, Gen;Wu, Renhua;Chang, Yongmin;Kang, Duksik
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.4
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    • pp.259-266
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    • 2013
  • Purpose : To investigate the blood pharmacokinetics and bio-distribution of DTPA-bis-amide (L3) Gd(III) complexes. Materials and Methods: The pharmacokinetics and bio-distribution of Gd $(L3)(H_2O){\cdot}nH_2O$ were investigated in Sprague-Dawley rats after intravenous administration at a dose of 0.1 mmol Gd/kg. The Gd content in the blood, various tissues, and organs was determined by ICP-AES. Blood pharmacokinetic parameters were calculated using a two-compartment model. Results: The half-lives of ${\alpha}$ phase and ${\beta}$ phase Gd $(L3)(H_2O){\cdot}nH_2O$ were $2.286{\pm}0.11$ min and $146.1{\pm}7.5$ min, respectively. The bio-distribution properties reveal that the complex is mainly excreted by the renal pathway, and possibly excreted by the hepatobiliary route. The concentration ratio of Gd (III) was significantly higher in the liver and spleen than in other organs, and small amounts of Gd (III) ion were detected in the blood or other tissues of rats only after 7 days of intravenous administration. Conclusion: The MRI contrast agent Gd $(L3)(H_2O){\cdot}nH_2O$ provides prolonged blood pool retention in the circulation and then clears rapidly with minimal accumulation of Gd(III) ions. The synthesis of gadolinium complexes with well-balanced lipophilicity and hydrophilicity shows promise for their further development as blood pool MRI contrast agents.

The Preparation for Sintered Body of $CeO_2$ Based Complex Oxide in Low Temperature Solid Oxide Fuel Cells Using Colloidal Surface Chemistry (콜로이드 계면화학을 이용한 저온형 고체전해질용 $CeO_2$계 복합 산화물의 소결체 제조)

  • 황용신;최성철
    • Journal of the Korean Ceramic Society
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    • v.37 no.7
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    • pp.705-712
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    • 2000
  • In this study, the dispersion stability of CeO2 based complex oxide was studied, and density, porosity, and microstructure of green body were investigated using colloid surface chemistry to manufacture the Gd2O3 doped CeO2 solid electrolyte in an aqueous system. To prepare the stable slurry for slip casting, the dispersion stability was examined as a function of pH using ESA(electrokinetic sonic anplitude) analysis. The dynamic mobility of particles was enhanced with anionic and cationic dispersant were added the amount of 0.5wt% respectively, but pH value in slurries didn't move to below 6.0 because of the influence of dopants. This phenomenon also appeared in the CeO2-Y2O3 and CeO2-Sm2O3 systems, so it could be inferred that rare earth dopants such as Gd2O3, Sm2O3 and Y2O3 not only have the similar motion with changing pH in an aqueous system but also can be dissolved in the range of pH 6.0∼6.5. In CeO2-Gd2O3 system, when the anionic dispersant was added the amount of 0.5wt% and pH value in slurries was fixed at 9.5, the green body density was 4.07g/㎤, and the relative density of sintered body was 95.2%. It could be inferred from XRD analysis that Gd3+ substituted into Ce4+ site because there was no free Gd2O3 peak.

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Variations of Magnetic Properties and Composition with Deposition Ratio in GdFe Thin film (GdFe 박막의 증착속도에 따른 조성 및 자기특성의 변화)

  • Choe, Yeong-Geun;Park, Chang-Man;Baek, Ju-Yeol;Lee, Gi-Am;Hwang, Do-Geun
    • Journal of the Korean Magnetics Society
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    • v.2 no.3
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    • pp.257-262
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    • 1992
  • We have studied the variations of composition and magnetic properties with deposition rate in GdFe thin films by means of DC magnetron sputtering with the enhanced complex target method. Gd atomic percent was decreased with the increase of deposite rate. It appeared the transition phenomena at 1.0 ${\AA}/s the deposition rate. Also, the deposition rate increased with input power and the sputtering efficience was proportional to the number of Gd chip. An increase of the coercivity with input power can be interpreted by the large size of Fe crystal grains. We have introduced by the diffusion guard sputtering and it was effective for reproducibility of the sample. We have measured ${\theta}_k$ with Kerr angle gauge, and could observe that the ${\theta}_k$ was little varied with input power.

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A Study on the Hydrolysis of Sarin and Soman by Merrifield-Type Diaminatedpolystyrene-Cu (II) Heterogeneous Polymers (Merrifield-Type Diaminatedpolystyrene-Cu (II) 불균일 촉매에 의한 Sarin과 Soman 분해반응 연구)

  • 정우영;계영식
    • Journal of the Korea Institute of Military Science and Technology
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    • v.3 no.1
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    • pp.164-175
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    • 2000
  • Three compounds of Cu(II)-loaded N,N,N'-trimethylethylenediaminated Merrifield-type polymers were synthesized with yields higher than 80%, and the hydrolysis reaction rates of O-isopropylmethyl-phosphonofluoridate(GB) and O-pinacolylmethylphosphonofluoridate (GD) catalyzed by them have been surveyed. GB and GD hydrolysis by Cu(II)-loaded polymers occurs via intermediate complex mechanism where rapid equilibrium to form intermediate complex between substrate and Cu(II)-loaded polymers($K_f$) is followed by rate determining hydrolysis step($k_1$). The measured activation parameters for $k_1$ are ${\Delta}H^{\ddag}$ : $17.75{\pm}0.98kJ/mol$ ${\Delta}S^{\ddag}$ / : $-218.42{\pm}3.35J/mol$ K, $E^{\circ}_a$ : $20.22{\pm}0.98kJ/mo1$ for GB and ${\Delta}H^{\ddag}$ / : $11.16{\pm}1.15kJ/mol,$${\Delta}S^{\ddag}$ /: $-258.57{\pm}3.93J/mol$ K, $E^{\circ}_a$ : $13.64{\pm}1.15 kJ/mol$ for GD. Standard enthalpy/entropy changes corresponding to the intermediate complex formation constant $K_f$ are ${\Delta}H^{\circ}$ : $37.05{\pm}2.19 kJ/mo1,$$ {\Delta}S^{\circ}$ : $163.12{\pm}7.49 J/mol$ K and ${\Delta}H^{\circ}$ : 418.59{\pm}2.04 kJ/mol,$ ${\Delta}S^{\circ}$ : 4111.92{\pm}6.98 J/mol$ K for GB and GD, respectively, The electron push-pull mechanism by Cu(II)-loaded polymers lowers the P-F bond breaking energy(~400 kJ/mol) to less than 1/20 compared to the case in which no Cu(II)-loaded resin presents. Analysis of $K_f$ and 4k_1$ over pH=6.5~8.0 range suggest that the GB and GD hydrolysis occurs intramolecularily with $pK_a$ =7.29 for ligated $H_2O$ and $t_{1/2}$=36.9 sec, $pK_a$ = 7.06 and $t_{1/2}$=177.7 sec for GB and GD, respectively.

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