• Title/Summary/Keyword: Polyethylene glycol

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Study on the Hydrophilicity of Modified Polyester (개질시킨 폴리에스테르 중합체의 친수성 연구)

  • Jung, Byung-Ok
    • Applied Chemistry for Engineering
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    • v.9 no.6
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    • pp.930-934
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    • 1998
  • The modified poly(ethylene terephthalate) (PET) was synthesized by copolymerizing dimethyl terephthalate with ethylene glycol, polyethyleneglycol, and dodecylbenzene sulfonate as a surfactant. After characterization of viscosity, color, and contant angle, hydrophilic characteristics of the modified PET depending on additives was discussed.

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Mechanical properties of domestic small-diameter logs treated with Polyethylene glycol (PEG(Polyethylene Glycol)처리재의 역학적 특성)

  • 권구중;김남훈
    • Journal of the Korea Furniture Society
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    • v.12 no.2
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    • pp.19-27
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    • 2001
  • This study was carried out to investigate the mechanical properties of woods treated with 30% aqueous solution of PEG 1000. Compressive, bending and shearing strengths were slightly decreased by PEG treatment. Absorbed energy in impact bending did not show any significant differences between untreated and PEG-treated woods.

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Enhancing Transfection Efficiency Using Polyethylene Glycol Grafted Polyethylenimine and Fusogenic Peptide

  • Lee, Haeshin;Jeong, Ji-Hoon;Lee, Je-Hoon;Park, Tae-Gwan
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.6 no.4
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    • pp.269-273
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    • 2001
  • This study presents a new formulation method for improving DNA transfection effi-ciency using a fusogenic peptide and polyethylene glycol-grafted polyethylenimine. Succinimidyls succinate polyethylene glycol (PEG-SSA) was conjugated with polyethylenimine(PEL). PEL is well known for a good endosomal escaping and DNA condensign agent. The positively charged syn-thetic fusogenic peptide, KALA was coated on the negatively charged PEG-g-PEI/DNA and PEI/DNA complexes. The KALA/PEI/ DNA complexes exhibited aggregation behavior at higher KALA coating amount with an effective diameter of around 1,000 nm. However, the LALA/PEG-g-PEI/DNA complexes were 100-300 nm in size with a surface zeta-potential (ζ)value of about +20mV. The conjugated PEG molecules suppressed any KALA-mediated inter-particle aggregation, and thereby improved the transfection efficiency, Consequently, the transfection efficiency of the KALA/PEG-g-PEI/DNA complexes was obtained by utilizing both the fusogenic activity of KALA and the steric repulsion effect of PEC.

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Polymorphism of Sulpiride and Its Pharmaceutical Applications ( III ) -Dissolution Kinetics of Sulpiride Polymorphs- (Sulpiride의 Polymorphism 및 그 약제학적(藥劑學的) 연구(硏究) (제3보)(第三報) -Polymorph에 따른 용출속도(溶出速度)-)

  • Lee, Min-Hwa;Kim, Kil-Soo
    • Journal of Pharmaceutical Investigation
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    • v.12 no.3
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    • pp.55-63
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    • 1982
  • The dissolution kinetics for polymorphs of sulpiride, the effect of polyethylene glycol 4000 on the dissolution kinetics of sulpiride polymorphs and the dissolution rate difference between the tablets of polymorph form I and form II were investigated. The results could be summerized as followings: 1. The dissolution rates of two polymorphs of sulpiride were significantly different and the thermodynamic parameters calculated from dissolution kinetics were as follows; transition temperature $98^{\circ}C$, enthalpy change, -2.108 kcal/mole, free energy change, -783 cal/mole $(31.0^{\circ}C)$. 2. The dissolution rates of the two polymorphs of sulpiride containing polyethylene glycol 4000 were significantly diefferent in 0.01N HCl but the effect of polyethylene glycol on the dissolution rates of two polymorphs was not significant at low concentration of polyethylene glycol 4000. The study on the effect by stirring speed showed that at lower stirring speed the promotion rate of dissolution of polymorph form I is greater than that of form II. 3. In the case of tablets the dissolution rates of polymorph form I of sulpiride was two fold as compared with the results obtained from form II.

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Rectal Absorption of Acetaminophen from Polyethylene Glycol and Witepsol Suppositories (아세트아미노펜의 Polyethylene glycol 및 Witepsol 좌제의 직장흡수 - 병원제제를 목적으로 한 아세트아미노펜좌제의 조제 및 유용성 검토-)

  • Lee, Hye Suk;Jin, Sun Kyung;Choi, Jung Hwa;Ku, Young Soon
    • Korean Journal of Clinical Pharmacy
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    • v.8 no.2
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    • pp.143-146
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    • 1998
  • Acetaminophen (APAP) suppositories with active ingredients, i.e., polyethylene glycol (PEG), Witepsol H-15 (WH), were prepared for hospital use and investigated on their drug release characteristics and pharmacokinetics. WH was employed as oil-soluble base with an aim of reducing fragility and mucosa irritancy that are common drawbacks found in PEG suppositories. Also hollow type suppository was tried as compared with conventional type suppository. Drug release tests revealed that in most formulations, more than $80\%$ of loaded APAP were released within 20 minutes, except for APAP-WH hollow type suppositories. Significant differences in the plasma concentration profile were observed among four type suppositories. $T_{max}$ of APAP-PEG and APAP-WH suppositories were 90 and 60 minutes, respectively, in hollow types. APAP-WH hollow type suppositories demonstrated fast absorption rates of APAP as compared with those of APAP-PEG suppositories. No burst effect was observed from APAP-WH suppository in contrast to APAP conventional type suppository, whereas AUCs of all the suppositories were similar. APAP-WH hollow type suppository may be an useful dosage form for hospital use.

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Effects of the Methods of Polyethylene Glycol Impregnation and Drying on the Volumetric Shrinkage of Wood (Polyethylene Glycol 주입방법과 건조방법이 목재 부피수축률에 미치는 효과)

  • Lee, Won-Hee;Kang, Chun-Won;Hong, Seung-Hyun;Kang, Ho-Yang
    • Journal of the Korea Furniture Society
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    • v.27 no.1
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    • pp.43-48
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    • 2016
  • PEG (Polyethylene glycol) impregnation in wood reduces the occurrence of checking during kiln drying. The volumetric shrinkages of wood PEG impregnated by pressure (PEG-P) or soaking (PEG-S) methods, and oven-dried by vent (VD) or air-tight (AD) methods were measured and compared with the controls. The average oven-dry weight of PEG impregnated specimens was larger than that of the controls by 3.6 g, but was not influenced by the drying methods. The average of the total volumetric shrinkage of PEG-P-VD specimens was the least (2.3%), while that of CON-S-AD specimens was the largest (28.9%). Within a drying method the total volumetric shrinkage of the control was the largest followed by PEG-S and PEG-P specimens, which implied that residual PEG in wood restrained its shrinkage during drying.

The Stability of Piroxicam in Propylene Glycol (프로필렌글리콜에서의 피록시캄의 안정성)

  • Shin, Young-Shin;Shin, Young-Hee;Lee, Chi-Ho
    • Journal of Pharmaceutical Investigation
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    • v.18 no.4
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    • pp.203-208
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    • 1988
  • The stability and solubility of piroxicam in propylene glycol (PG), polyethylene glycol (PEC), and PG-water cosolvents have been studied by using high performance liquid chromatography. The degradation rate followed an apparent first-order kinetic and the reaction rate constants at 70, 80, and $90^{circ}C$ were determined. From these rate constants, the activation energy and the rate constant of piroxicam at $25^{circ}C$ in pure PG calculated by Arrhenius equation were 23.34 kcal/mole and $7.0\;{\times}\;10^{-4}\;day^{-1}$, respectively. Both of PG and PEG increased the solubility of the drug, but PEG was more effective.

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Syntheses of Biologically Non-Toxic ZnS:Mn Nanocrystals by Surface Capping with O-(2-aminoethyl)polyethylene Glycol and O-(2-carboxyethyl)polyethylene Glycol Molecules

  • Kong, Hoon-Young;Song, Byung-Kwan;Byun, Jonghoe;Hwang, Cheong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.4
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    • pp.1181-1187
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    • 2013
  • Water-dispersible ZnS:Mn nanocrystals were synthesized by capping the surface of the nanocrystal with O-(2-Aminoethyl)polyethylene glycol (PEG-$NH_2$, Mw = 10,000 g/mol) and O-(2-Carboxyethyl)polyethylene glycol (PEG-COOH, Mw = 10,000 g/mol) molecules. The modified PEG capped ZnS:Mn nanocrystal powders were thoroughly characterized by XRD, HR-TEM, EDXS, ICP-AES and FT-IR spectroscopy. The optical properties were also measured by UV/Vis and photoluminescence (PL) spectroscopies. The PL spectra showed broad emission peaks at 600 nm with similar PL efficiencies of 7.68% (ZnS:Mn-PEG-NH2) and 9.18% (ZnS:Mn-PEG-COOH) respectively. The measured average particle sizes for the modified PEG capped ZnS:Mn nanocrystals by HR-TEM images were 5.6 nm (ZnS:Mn-PEG-NH2) and 6.4 nm (ZnS:Mn-PEG-COOH), which were also supported by Debye-Scherrer calculations. In addition, biological toxicity effects of the nanocrystals over the growth of wild type E. coli were investigated. They showed no biological toxicity to E. coli until very high concentration dosage of 1 mg/mL of the both nanocrystal samples.