• 제목/요약/키워드: Stability Agent

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Preparation of $^{125}I-Iodotyraminehemisuccinyltaxol\;(^{125}ITHT)$ for Competitive Taxol Radioimmunoassay (Taxol 방사면역측정을 위한 $^{125}I-Iodotyraminehemisuccinyltaxol\;(^{125}ITHT)$의 제조)

  • Lee, Tae-Sup;Awh, Ok-Doo;Choi, Tae-Hyun;Kim, Hyun-Suk;Hong, Jun-Pyo;Lee, Eun-Sook;Choi, Chang-Woon;Lim, Sang-Moo
    • The Korean Journal of Nuclear Medicine
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    • v.36 no.2
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    • pp.121-132
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    • 2002
  • Purpose : Taxol(Paclitaxel), an antineoplastic agent, has been used in the treatment of ovarian and breast cancers. The determination of optimal Taxol concentrations in human serum was required for enhancing therapeutic effect and maintaining the appropriate Taxol level in blood. This study was aimed to synthesizeradiolabeled Taxol derivatives as radiotracer in competitive radioimmunoassay for monitoring Taxol concentrations in blood and to determine the usefulness of its derivatives. Materials and Methods : Hemisucdcinyltaxol(HT) was synthesized by esterification of Taxol with succinic anhydride. Tyraminehemisuccinyltaxol(THT) was synthesized by coupling of HT with tyramine using isobutylchlormate as coupling agent and purified by HPLC. By using chloramine-T($5.25mg/ml,\;10{\mu}{\ell}$) as oxidant agent, THT($4mg/ml,\;30{\mu}{\ell}$) was labeled wity $^{125}I\;(37MBq,\;1mCi)$. To estimate the stability of purified THT, $^{125}I-iodotyraminehemisuccinyltaxol(^125}ITHT)$ was dissolved in 80% acetonitrile aqueous solution, and the solution was incubated at $4^{\circ}C\;and\;37^{\circ}C$ for 7 days. At various time intervals, the stability of THT and $^{125}ITHT$ was monitored. The titer of Taxol monoclonal antibody, 3G5A7, was determined by competitive radioimmunoassay using $^{125}ITHT$ as a labeled antigen. A standard dose-response curve was demonstated by Taxol competitive radioimmunoassay. Resulls : HT and THT were synthesized with 79.9% and 19.5% yield, respectively. The labeling yield of $^{125}ITHT$ was 93%. After 7 days, the chemical purity of THT was 96.5% at $4^{\circ}C$, and 97.5% at $37^{\circ}C$. After 3 days, $^{125}ITHT$ was stable with 94.7% at $4^{\circ}C$ and 93.4% at $37^{\circ}C$. After 7 days, fadiochemical purity was diminished to 88.1% at $37^{\circ}C$. The titer of Taxol monoclonal antibody, 3G5A7, was determined to 1:256. A standard dose-response curve demonstated good collinearity ($R^2=0.971$) as Taxol concentration-dependent manner. Conclusion : Competitive radioimmunoassay using $^{125}I-iodotyraminehemisuccinytaxol$ as radiotracer could be used to monitor for concentration of Taxol in the human serum.

Stabilization of Covalently Cross-Linked SPEEK/Cs-Substituted HPA Composite Membranes for Water Electrolysis ($Cs^+$치환에 따른 수전해용 공유가교 SPEEK/HPA 복합막의 안정화)

  • Jee, Bong-Chul;Ha, Sung-In;Song, Min-Ah;Chung, Jang-Hoon;Moon, Sang-Bong;Kang, An-Soo
    • Transactions of the Korean hydrogen and new energy society
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    • v.22 no.1
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    • pp.1-12
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    • 2011
  • To improve the mechanical properties, such as durabilities and antioxidative characteristics, the covalently cross-linked (CL-) SPEEK (sulfonated polyether ether ketone)/Cs-substituted HPA (heteropoly acid) organic-inorganic composite membranes (CL-SPEEK/Cs-HPAs), have been intensively investigated. The composite membrane were prepared by blending cesium-substituted HPAs (Cs-HPAs), including tungstophosphoric acid (TPA), molybdophosphoric acid (MoPA), and tungstosilicic acid (TSiA) with cross-linking agent content of 0.01 mL. And composite electrolytes composed of Cs-HPAs, prepared by immersion (imm.) and titration (titr.) methods to increase the stability of HPAs in water, were applied to polymer electrolyte membrane electrolysis (PEME). As a result, the proton conductivity of Cs-substituted composite membranes increased rapidly over $60^{\circ}C$ but mechanical properties, such as tensile strength, decreased in accordance with added Cs content. The bleeding-out of Cs-TPA membranes by titration method (50 vol.% Cs) decreased steadily to 2.15%. In the oxidative stability test by Fenton solution, the durability of membranes with Cs-HPA significantly increased. In case of CL-SPEEK/ Cs-TPA membrane, duration time increased more than 1200 hours. It is expected that even though CL-SPEEK/Cs-MoPA membrane shows the high proton conductivity, electrocatalytic activity and cell voltage of 1.80 V for water electrolysis, the CL-SPEEK/Cs-TPA (imm.) is more suitable as an alternative membrane in real system with the satisfactory proton conductivity, mechanical properties, anti-oxidative stability and cell voltage of 1.89 V.

Lamellar-bio nano-hybrid; The Study for Stability of Catechin (Green Tea: EGCG) Using 3-Dimensional Liposome (라멜라-바이오 나노하이브리드: 3 Dimension-liposome을 이용한 카테킨(EGCG)에 안정화에 대한 연구)

  • Hong Geun, Ji;Jung Sik, Choi;Hee Suk, Kwon;Sung Rack, Cho;Byoung Kee, Jo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.2
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    • pp.201-205
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    • 2004
  • In these several years, as many people have been attracted by the functional cosmetics, there are a lot of study to enhance the stability of active ingredients for light, heat, oxygen, etc. in the academic and industrial field. Especially, catechin is well known as strong anti-oxidant, anti-inflammatory and reducing agent for oxidative stress but it is very unstable for light, heat, oxygen. etc. In this study, the stability and skin penetration of catechin are improved by 3-dimensional method. As I-dimension, porous silica is prepared using sol-gel method, and then catechin is adsorbed in pores of silica. As 2-dimension, solid lipid nanoparticles (SLN) are obtained using non-phospholipid vesicles. Finally 3-dimension is completion through lamellar phase self-organization that combines SLN catechin with skin lipid matrix. We used laser light scattering system, cyro-SEM, chromameter, HPLC and image analyzer to analyze our 3-dimentional systems. According to chromameter date, the color stability of 3-dimensional catechin is enhanced by 5-10 times compared with general liposome systems. We also confirmed through HPLC analysis that 3-dimensional catechin is more long lasting. The effect of skin penetration and wrinkle reduction are improved, too.

Effects of Astaxanthin on the Oxidative Stability and Quality Characteristics of Emulsified Sausages during Cold Storage (아스타잔틴 첨가가 유화형소시지의 저장 중 산화 안정성 및 품질 특성에 미치는 영향)

  • Seo, Jin-Kyu;Park, Jun-Young;Kim, Beom-Hak;Lee, Hyun-Jun;Kang, Seong-Gyun;Yang, Han-Sul
    • Journal of agriculture & life science
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    • v.53 no.3
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    • pp.41-49
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    • 2019
  • Consumers are interested in natural ingredient that replace synthetic antioxidants in meat products. This study was carried out to investigate the effects of astaxanthin (AX) on the oxidative stability and quality characteristics of emulsified sausages during cold storage. Emulsified sausages were prepared as follows: manufactured without AX and BHT (Control), added with 500 mg/kg of BHT (BHT), and added with 80 mg/kg of AX (AX). Addition of AX showed no significant difference in pH, emulsion stability and cooking yield of emulsified sausages (p>0.05). However, the initial color retentivity was the same as that of synthetic antioxidant such as BHT treatment, and the redness was higher when AX treatment was added (p<0.05). The lipid oxidation showed the lowest value in the BHT treatment at the end of storage and the AX treatment also was significant lower than that of control (p<0.05). Hardness was lower in the all treatments at the end of storage than in the control (p<0.05). Therefore, astaxanthin can be used as a color enhancing agent for meat products as well as an natural antioxidant in replacing of BHT which is as synthetic antioxidant.

Solubilization of CPD, a Novel Antivirus Compound Containing Pirimidine Structure, in Aqueous Solution (신규 피리미딘 구조를 함유한 항바이러스성 화합물 CPD의 수용액중 가용화)

  • Song Sukgil;Kweon Ho-Seok;Chung Youn Bok
    • YAKHAK HOEJI
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    • v.50 no.1
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    • pp.1-7
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    • 2006
  • The purpose of the present study was to formulate the aqueous solution of 1-cyclopent-3-enylmethyl-6(3,5-dimethyl-benzoyl)-5-ethyl-1H-pyrimidine-2,4-dione (CPD), a novel antivirus compound containing pirimidine structure. For this purpose, the effects of various solubilization agents such as cosolvents [ethanol, propylene glycol (PG), polyethylene glycol 300 (PEG 300), polyethylene glycol 400 (PEG 400), glycerin], surfactants (Tween 80, Cremophor$^{(R)}$ RH40, Cremophor$^{(R)}$ EL, Poloxamer 407, Poloxamer 188) and a complexation agent [hydroxypropyl-${\beta}$-cyclodextrin (HPBCD)] , on the solubility of CPD in aqueous solution were evaluated. The solubility of CPD in water was under $1\;{\mu}g/ml$ at $20^{\circ}C$. Cosolvents such as ethanol, PG, PEG 300, PEG 400 and glycerin did not enhance the solubility of CPD at the $0{\sim}40\%$ concentration range. The solubility of CPD was significantly elevated by the addition of cosolvents over the $80\%$ concentration range. On the other hand, tween 80, Cremophor$^{(R)}$ L, Cremophor$^{(R)}$ RH40, and HPBCD showed enhanced effects on the solubility of CPD. The enhanced effects of Poloxamer 407 or Poloxamer 188 on the CPD solubility were less pronounced compared with tween 80, Cremophor$^{(R)}$ L or Cremophor$^{(R)}$ RH40. As a results, tween 80 aqueous solution was selected as an optimum solvent system. The aqueous solutions containing $20\%$ tween 80 were formulated as a dosing solution containing CPD for its intraperitoneal and intrahypodermic administration, respectively, The formular showed physical stability after stored for 7 days at $4^{\circ}C$.

Formulation Design and Evaluation of Ketorolac Tromethamine Hydrogel for Transdermal Delivery System (경피흡수를 위한 케토롤락 하이드로겔의 제제설계 및 평가)

  • Cho, In-Sook;Lee, Gye-Won;Lee, Jong-Hwa;Jee, Ung-Kil
    • Journal of Pharmaceutical Investigation
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    • v.33 no.1
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    • pp.21-28
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    • 2003
  • Ketorolac tromethamine(KT) is a nonsteroidal agent with potent analgesic and moderate anti-inflammatory activity. The lipid-water partition coefficient of KT was evaluated and KT gel was formulated as a gel containing different pH, different concentrations of polymer (poloxamer 407, carbopol 941), propylene glycol, ethanol and various enhancers. The resulting KT gels were evaluated with respect to their viscosity, in vitro drug permeation rate through hairless mouse skin and stability. In n-octanol and chloroform, the lipid-water partition coefficient of KT was the highest at pH 4 phosphate buffer. The apparent viscosity of KT gel increased with an increase in gel pH, polymer and enhancer concentration. But the apparent viscosity of KT gel decreased with an increase in ethanol concentration. The permeation rate of KT through hairless mouse skin from gels different pH was maximum at pH 4 which is close to KT $pK_{a}$ 3.54. The permeation rate decreased with an increase in polymer, propylene glycol concentration. But the permeation rate increased with an increase in ethanol. The increase of drug concentration from 1 to 3% induced linear increase in permeation rate. The best enhancer was the combination of $Labrasol^{\circledR},\;Transcutol^{\circledR}$, oleic acid and l-menthol. In the accelerated stability test(25, 40 and $50{\circ}C$), pH 5 gel was most stable and pH 4 gel was most unstable for 90 days.

Solubilization of IH-901, a Novel Intestinal Metabolite of Ginseng Saponin, in Aqueous Solution (인삼사포닌의 소장내 최종대사물인 IH-901의 수용액중 가용화)

  • Kwon, Oh-Seung;Chung, Youn-Bok
    • Journal of Pharmaceutical Investigation
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    • v.34 no.5
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    • pp.385-391
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    • 2004
  • The purpose of the present study was to formulate the aqueous solution of $20-O-{\beta}-D-glucopyranosyl-20(S)-protopanaxadiol\;(IH-901)$, an intestinal bacterial metabolic derivative from Ginseng protopanaxadiol saponin. For this purpose, the effects of various solubilization agents such as cosolvents [ethanol, propylene glycol (PG), polyethylene glycol 300 (PEG 300), polyethylene glycol 400 (PEG 400), glycerin], surfactants $(Tween\;80,\;Cremophor^{\circledR}\;RH40,\;Cremophor^{\circledR}\;EL,\;Poloxamer\;407,\;Poloxamer\;188)$ and a complexation agent $[hydroxypropyl-{\beta}-cyclodextrin\;(HPBCD)]$, on the solubility of IH-90l in aqueous solution were evaluated. The solubility of IH-901 in water was under $1\;{\mu}g/ml\;at\;20^{\circ}C$. Cosolvents such as ethanol, PG, PEG 300, PEG 400 and glycerin did not enhance the solubility of IH-901 at the 0 - 40% concentration range. The solubility of IH-901 was significantly elevated by the addition of cosolvents over the 80% concentration range. On the other hand, tween 80, $Cremophor^{\circledR}\;EL,\;Cremophor^{\circledR}\;RH40$ and HPBCD showed enhanced effects on the solubility of IH-901. The enhanced effects of Poloxamer 407 or Poloxamer 188 on the IH-901 solubility were less pronounced compared with $Cremophor^{\circledR}\;EL\;or\;Cremophor^{\circledR}\;RH40$. As a results, $Cremophor^{\circledR}$ aqueous solution was selected as an optimum solvent system. The aqueous solutions containing 10% $Cremophor^{\circledR}\;EL$ and 7% $Cremophor^{\circledR}\;RH40$ were formulated as dosing solutions containing 5.0 mg/ml of IH-901 for its intravenous and oral administration, respectively. The formular showed physical stability after stored for 7 days at $4^{\circ}C$.

Formation of Lipid-LCG with Hydrogenated Lecithin (수소첨가 레시친을 사용한 Lipid-LCG의 생성)

  • Kim, In-Young;Lee, Gun-Bong;Zhoh, Choon-Ku;Kang, Sam-Woo
    • Journal of the Korean Applied Science and Technology
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    • v.19 no.1
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    • pp.10-18
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    • 2002
  • In this study, it should be mentioned that Lipid-LCG can be prepared with the main compound of hydrogenated lecithin in oil-in water emulsion. The results of its physical property and stability are as follows. First, the best suitable compositions of Lipid-LCG are made from 4.0wt% of the hydrogenated lecithin, 4.0wt% of cetostearyl alcohol as emulsifier and gelling agent, 3.0wt% of butylene glycol and 2.0wt% glycerin as moisturizers, 3.0wt% of cyclomethicone, 3.0wt% of isononyl-isononanoate, 3.0wt% of capric/caprylic triglycerides, 3.0wt% of macadamia oil as emollients. Second, As the optimum conditions to form Lipid-LCG, which figured out 6.0 ${\pm}$ 1.0 for pH level, 32kg/mm, min for hardness to make a .essence to be formed the ternary phase of liquid crystal(multi-lamellar type). Third, as the analytical result of this system, it obtained that particle size is $1{\sim}8{\mu}m$ level, and is certified with it at 400 and 1,000 magnifications by microscope. The stability of Lipid-LCG is very stable on condition of a low temperature ($4^{\circ}C$), a room temperature ($25^{\circ}C$) and a high temperature ($40^{\circ}C$), which is not to be split in for a long time(for 3-month). We produced our own moisturizing essence, which has a good affinity to skin by means of this system.

Synthesis and Surface Active Properties of Amphoteric Surfactant Derivatives(II);Surface Active Properties of N-Alkyl or Acyl Hydroxy sulfobetaines (양쪽성 이온 계면활성제의 유도체합성 및 계면성에 관한 연구(제2보);N-알킬 혹은 아실히드록시 술포베타인류의 계면성)

  • Lee, J.H.;Ha, J.W.;Park, H.J.;No, Y.C.;Nam, K.D.
    • Journal of the Korean Applied Science and Technology
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    • v.11 no.1
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    • pp.79-85
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    • 1994
  • All the activities and physical properties including surface tension' foaming power, foam stability, emulsifying power, dispersion effect of 3-(N, N-dimethyl N-alkylammonio)-2-hydroxyY-1-propane sulfonate (HSB)류와 3-CN-alkylamidopropyl-N,N-dimethylamm-onjo)-2-hydroxy-1-propane sulfonate (APSB) aquous solution were measured and critical micelle concentration was evaluated. Their cmc of hydroxy sulfobetaine derivatives evaluated by the surface tension method was $1.0{\times}10^{-3}{\sim}1.0{\times}10^{-4}$ mol/l, and surface tension of the aquous solution was decreased to $27{\sim}38dyne/cm$. The experimental results for foaming power, foam stability, emulsifying power in liquid paraffin showed a good surface active properties, especially, dispersion effect in ferric oxide exhibited some efficient surface active properties, and then it would be expected to application as detergent and dispersion agent.

Synthesis and in vitro evaluation of 99mTc-labeled tetraiodothyroacetic acid for tumor angiogenesis imaging

  • Kim, Hyunjung;Koo, Hyun-Jung;Choe, Yearn Seong
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.6 no.1
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    • pp.3-9
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    • 2020
  • Tetraiodothyroacetic acid (tetrac) is a derivative of thyroid hormone T4 and causes anti-angiogenesis by blocking T4 binding to integrin αvβ3. In this study, we synthesized [99mTc]Tc-Cys-Asp-Gly(CDG)-tetrac and evaluated it in vitro as a tumor angiogenesis imaging ligand. The CDG was conjugated to tetrac as a chelator for technetium-99m labeling. The cold vial containing CDG-tetrac, sodium glucoheptonate, and reducing agent was completed under nitrogen-filled atmospheric glove bag. [99mTc]Tc-CDG-tetrac was synthesized in quantitative yield by heating the cold vial with [99mTc]TcO4- at 100℃ for 30 min. In vitro serum stability of [99mTc]Tc-CDG-tetrac was measured by incubating the radioligand in 50% fetal bovine serum at 37℃ and analyzing the incubation mixture by radio-TLC, which showed high stability over 6 h (≥ 98%). Cell binding study was carried out by incubating [99mTc]Tc-CDG-tetrac with human umbilical vein endothelial (HUVE) cells at 37℃ for 6 h. The cell binding of the radioligand increased from 100% at 0.5 h to 293.7% at 6 h in a time-dependent manner. For blocking study, the cells were incubated with the radioligand in the presence of either tetrac (20 μM) or cRGDyK (20 μM) at 37℃ for 4 h. The results demonstrated that the cell binding of the radioligand was inhibited by tetrac (19.1%) or cRGDyK (35.6%), indicating specific binding of the radioligand to integrin αvβ3. Thus, this study suggests that [99mTc]Tc-CDG-tetrac may be a potential radioligand for tumor angiogenesis imaging.