• Title/Summary/Keyword: Dimethyl sulfoxide

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Selective Adsorption of a Symmetrie Theophylline Imprinted Membrane Prepare by a Wet Phase Inversion Method (습식 상 전이법으로 제조된 Theophylline 각인 대칭 막의 선택적 흡착)

  • 박중곤;오창엽;서정일
    • KSBB Journal
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    • v.17 no.2
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    • pp.207-211
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    • 2002
  • The theophylline imprinted membrane was prepared by a wet phase inversion method. Theophylline was implanted during copolymerization of acrylonitrile with acrylic acid or implanted in the dimethyl sulfoxide solution containing10 wt% copolymer, p(AN-co-AA). Rolling the glass plate, on which the copolymer solution was cast, in water removed the sponge layer and thus made the membrane symmetric. The adsorption selectivity of the membrane toward template molecule was increased with the coagulation temperature of the membrane and the initial concentration of the theophylline and caffeine mixture.

Effects of Various Kinds and Concentrations of Cryoprotectants on Viabilities of Ultrarapidly Frozen 4-cell Mouse Embryos and Morulae (생쥐 4세포기 및 상실배기 수정란의 초급속동결에 있어서 동결보호제의 종류와 농도가 생존성에 미치는 영향)

  • 임준호;신상태;강만종;한용만;이경광
    • Journal of Embryo Transfer
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    • v.11 no.1
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    • pp.35-40
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    • 1996
  • This study was carried out to select the best cryoprotectant and to establish optimal concentration of the cryoprotectant in ultrarapid freezing of mouse 4-cell embryos and morulae, respectively. We investigated survival of ultrarapid frozen embryos according to various cryoprotectants such as glycerol, ethylene glycol, propylene glycol and dimethyl sulfoxide (DMSO). Suvival of the embryos frozen at different concentrations (3.0, 4.0 and 5.0 M) of indivisual cryoprotectant was also tested. Preimplantation developmental rate (96.3%, 83/86) of 4-cell mouse embryos treated with 4.0 M ethylene glycol after ultrarapid freezing and thawing was higher than those of other cryoprotectants (glycerol, propylene glycol and DMSO). In the ultrarapid freezing of mouse morulae, the highest developmental rate (98.8%, 89 /90) of the embryos to blastocysts was shown in the group of 5.0 M glycerol. Thus, these results demonstrate that 4.0 M ethylene glycol and 5.0 M glycerol are optimal for ultrarapid freezing of 4-cell mouse embryos and morulae, respectively.

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On the Development of Functional New Derivatives from Cellulose - Manufacturing of Reactive Cellulose Derivatives from Chlorinated Cellulose - (셀룰로오스로부터 기능성 신소재 개발에 관한 연구 - 염소화셀룰로오스로부터 반응성셀룰로오스의 제조 -)

  • Cho, Nam-Seok
    • Journal of the Korean Wood Science and Technology
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    • v.22 no.4
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    • pp.51-60
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    • 1994
  • Chlorodeoxycellulose derivatives have recently assumed importance since the halogen atoms can be changed with other functional groups to afford new derivatives of cellulose. Also, chlorinated cellulose has been employed as an intermediate in the preparation of various functional cellulose derivatives. In this study chlorodeoxycellulose was prepared by reaction of methylcellulose with mathanesulfonylchloride in N,N-dimethylformamide. Subsequently, conversion of the above chlorinated cellulose to unsaturated celluloseen was carried out by potassium tertiary butoxide in dimethyl sulfoxide. An anhydrocellulose as an intermediate for the reactive functional derivatives was made by simple alkali treatment. Preparation condition of allylated methylcellulose by using allylchloride and its thermal behavior were also described.

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Noninvasive study of Drug Delivery Systems using Nuclear Magnetic Resonance Microimaging (핵자기공명 현미영상법을 이용한 약물전달체계의 비파괴연구)

  • 이동훈;고락길
    • Journal of Biomedical Engineering Research
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    • v.18 no.2
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    • pp.173-178
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    • 1997
  • pH sensitive polymers have long been utilized as one important type among many interesting drug delivery systems. This is due to the reason of different pH environments in human organs, which requires different pH control mechanism depending upon the organs. In the present study the pH sensitivity was investigated for both pH sensitive and pH insensitive biopolymers using the diffusion effect along with the swelling effect. NMR microscopy was performed along with optical microscopy. For the analysis of diffusion effect, UMR Microscopy was perFormed to measure diffusion coefficients for various liquids such as distilled water, acetone and DMSO(dimethyl sulfoxide). Also, this technique is expected to contribute to the studies for many pH drug delivery systems.

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Toxicity of Cryoprotectants to Gametophytic Thalli of Red Algae Porphyra yezoensis

  • Choi, Youn-Hee;Nam, Taek-Jeong
    • Fisheries and Aquatic Sciences
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    • v.15 no.1
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    • pp.77-81
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    • 2012
  • We assessed the toxicity of cryoprotectant agents (CPAs) to gametophytic thalli of red alga Porphyra yezoensis at room temperature. The CPAs used were: dimethyl sulfoxide (DMSO), ethylene glycol (EG), glycerol (GC), 1,2-butanediol (1,2-BD), 1,3-butanediol (1,3-BD), 2,3-butanediol (2,3-BD), 1,3-propanediol (1,3-PD) and propylene glycol (PG). CPA concentrations of 10, 15, 20, 25, 30, 35, 40, 45, and 50% were employed with 30 or 60 s immersion. The toxicity of the eight CPAs to gametophytic thalli of P. yezoensis was in the order: 1,3-BD < DMSO ${\approx}$ 2,3-BD ${\approx}$ PG ${\approx}$ EG < GC < 1,3-PD ${\approx}$ 1,2-BD. All thalli were more sensitive to high CPA concentrations, and most (>75%) thalli survived exposure to 10-25% CPA for 60 s. These data will facilitate selection of the optimal cryoprotectant concentration for cryopreservation of P. yezoensis thalli.

A Model for Correlation of Various Solvatochromic Parameters with Composition in Aqueous and Organic Binary Solvent Systems

  • Aziz, Habibi-Yangjeh
    • Bulletin of the Korean Chemical Society
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    • v.25 no.8
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    • pp.1165-1170
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    • 2004
  • The applicability of the combined nearly ideal binary solvent/Redlich-Kister (CNIBS/R-K) equation for correlation of various solvatochromic parameters (SP) with composition is shown employing 84 experimental data sets for aqueous and organic binary solvent systems at temperatures ranging 15 to $75^{\circ}C$. The model provides a simple computational model to correlate/predict different SP values in various binary solvent systems. In proposed equations, $MPD_s$ (mean percentage deviations) are between 0.0500% and 6.9591% in mixtures of dimethyl sulfoxide with 2-methylpropan-2-ol and benzene with 2-methylpropan-2-ol, respectively. Correlation of the calculated and experimental values of various SP give an equation with an overall mean percentage deviation (OMPD) of 1.1900, $R^2$ = 0.99692, s.e = 0.01223 and F = 341925.51. Approximately 70% of the calculated SP values have IPD (individual percentage deviation) lower than one and it is possible to predict unmeasured SP values by using only eight experimental data.

Sperm Cryopreservation and Fertility of Post-thaw Sperm in River Puffer, Takifugu obscurus (황복(Takifugu obscurus) 정자의 냉동보존 및 해동정자의 수정능력)

  • 장영진;임한규;장윤정;김형선
    • Journal of Aquaculture
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    • v.12 no.1
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    • pp.1-5
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    • 1999
  • To obtain fundamental data for sperm cryopreservation in river puffer (Takifugu obscurus), the proper conditions of cryopreservation were investigated. In the sperm cryopreservation of river puffer, marine fish Rinser's solution (MFRS) was found to be good diluent and dimethyl sulfoxide (DMSO) was proved to be superior to glycerol as a cryoprotectant. The highest fertilization rate was achieved when river puffer sperms were cryopreserved with MFRS adding 5% DMSO.

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Preparation and Characterization of Wholly Aromatic Polybenzoxazole Copolymers Bearing Ether and Bulky Units

  • Han, So Hee;Lee, Eung Jae;Choi, Jae Kon
    • Elastomers and Composites
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    • v.55 no.3
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    • pp.205-214
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    • 2020
  • A series of wholly aromatic polyhyroxyamide (PHA) copolymers were prepared by direct polycondensation reaction of isophthalic acid and diacids containing bulky units with 3,3'-dihydroxybenzidine. The inherent viscosities of the PHAs measured at 35℃ in DMAc solution were in the range of 0.31-0.56 dL/g. The solubility study revealed that the PHAs were readily soluble in aprotic solvents such as, dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO), and N-methyl-2-pyrrolidone (NMP) at room temperature and in less polar solvent such as pyridine. However, the polybenzoxazole (PBO) copoymers were quite insoluble in all organic solvents except partially soluble in concentrated sulfuric acid and partially soluble in NMP containing LiCl. The PBO copolymers showed maximum weight loss temperature in the range of 593-632℃ and high char yields in the range of 65.0-71.2% at 900℃ in a nitrogen atmosphere.

Solution Polymerization of Acrylonitrile Using a Cosolvent System (DMSO/TBA) (혼합 용매계 (DMSO/TBA)를 이용한 아크릴로니트릴의 용액 중합)

  • ;;;Kim Bum-Sik
    • Textile Coloration and Finishing
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    • v.15 no.3
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    • pp.127-131
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    • 2003
  • Acrylonitrile(AN) was solution-polymerized in dimethyl sulfoxide(DMSO) and tertiary butyl alcohol(TBA) at 30, 40, $50^\circ{C}$ using a low temperature initiator, 2,2'-azobis(2,4-dimethylvaleronitrile) (ADMVN). The low temperature polymerization using ADMVN, DMSO, and TBA is to be successful in obtaining high molecular weight polyacrylonitrile(PAN) with less branches by solution polymerization. Throug a polymerization of AN in DMSO at $30^\circ{C}$, PAN having viscosity-average molecular weight$(M_v)$ of 931,000 was obtained. And then, during AN solution polymerization in DMSO and TBA using a cosolvent system the in-situ formation of microfibrillar structure has been discovered at the cosolvent composition of 24/1$(V_{DMSO}/V_{TBA})$. The simultaneous process of gelation and phase separation of long chain molecules may explain the in-situ formation of PAN fibers during polymerization.

Determination of Relative Reactivities of Free Hydroxyl Groups in β-Cyclodextrin, Amylose, and Cellulose by Reductive-Cleavage Method

  • 이창규;김은주;전중호
    • Bulletin of the Korean Chemical Society
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    • v.20 no.10
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    • pp.1153-1158
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    • 1999
  • β-Cyclodextrin, amylose, and cellulose were partially methylated and acetylated in order to examine the relative reactivities of 2-, 3-, and 6-OH groups to alkylation and acylation. The partially methylated samples of the polysaccharides were treated with excess of ethyl iodide and sodium hydroxide in dimethyl sulfoxide to convert all of the free hydroxyl groups to ethyl ether groups. The partially O-ethylated and O-methylated polysaccharides were reductively cleaved with triethylsilane in the presence of trimethylsilyl methanesulfonate and borontrifluoride etherate (5 : 1 by mole) and the resulting 4-OH group was acetylated and benzoylated to form mixtures of eight 4-O-acyl-1,5-anhydroalditols. The relative ratio of the alditol esters were analyzed by gas chromatography to determine the degree of substitution at each position. A similar sequence of reactions was carried out with partially acetylated polysaccharides. The results indicated that the order of relative reactivities for methylation are 2-OH > 6-OH > 3-OH and for acylation are 6-OH > 2-OH > 3-OH regardless of the anomeric configuration.