• Title/Summary/Keyword: Partition Coefficient

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Diffusion of Progesterone in Polyacrylamide Gel (Polyacrylamide gel에서 Progesterone의 확산 거동)

  • 김명희;김말남;민병례
    • Korean Journal of Microbiology
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    • v.28 no.3
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    • pp.278-282
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    • 1990
  • Diffusion and partition of progesterone into the polyacrylamide gel was examined. Diffusion coefficient of progesterone decreased down to an asymptotic value as the concentration of the organic solvents in the diffusing medium increased. However the partition coefficient diminished steadily. Crosslinking density in the gel didn't affected the diffusion coefficient considerably but lowered the partition coefficient due to the contraction of pore volume of the gel. Progesterone showed higher diffusion coefficient as well as partition coefficient in the polyurethane than in the polyacrylamide gel, which seems to be ascribed to the difference in hydrophobicity, pore volume and pore size of the polymer matrix.

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Applicability of the HPLC Method for the Estimation of Octanol/water Partition Coefficient to Pesticides of Domestic Use (국내 사용 농약을 대상으로 한 HPLC 방법에 의한 옥탄올/물 분배계수 추정법의 적용성 검토)

  • Kim, Kyun;Kwon, Jin-Wook;Kim, Yong-Hwa
    • Environmental Analysis Health and Toxicology
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    • v.16 no.4
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    • pp.189-196
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    • 2001
  • Octanol/water partition coefficients of 52 chemicals were calculated using RP-HPLC estimation method and predicted by computer program, PCHEM. The result showed relationship between literature values and RP-HPLC observed values (relative coefficient r$^2$=0.916), but the relationship of PCHEM values with literature values was lower than RP-HPLC value (relative coefficient r$^2$=0.795). The average difference in partition coefficient between the RP-HPLC method and flask-shaking method was log Kow=0.54, while the average difference between the values predicted form the computer program and flask- shaking method was log Kow = 0.36 Compared to octanol/water partition coefficients by 3 methods (Flask-shaking, RP-HPLC, computer prediction), the octanol/water partition coefficient values based on the flask-shaking method were very similar to the literature values, while the octanol/water partition coefficient values by RP-HPLC method without to consider the dead time, and computer prediction values did not significantly differ with the literature values.

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Determination and Temperature Dependence of n-Octanol/Water Partition Coefficients for Seven Sulfonamides from (298.15 to 333.15) K

  • Congliang, Zhang;Yan, Wang;Fuan, Wang
    • Bulletin of the Korean Chemical Society
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    • v.28 no.7
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    • pp.1183-1186
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    • 2007
  • A shake-flask method was used to determine the n-octanol/water partition coefficients of sulfamethazine, sulfadimethoxine, sulfamethoxydiazine, sulfamonomethoxine, sulfamethoxazole, sulfaquinoxaline and sulfachloropyrazine from (298.15 to 333.15) K. The results showed that the n-octanol/water partition coefficient of each sulfonamide decreased with the increase of temperature. Based on the fluid phase equilibrium theory, the thermodynamic relationship of n-octanol/water partition coefficient depending on the temperature is proposed, and the changes of enthalpy, entropy, and the Gibbs free energy function for sulfonamides partitioning in n-octanol/ water are determined, respectively. Sulfonamides molecules partitioning in n-octanol/water is mainly an enthalpy driving process, during which the order degrees of system increased. The temperature effect coefficient of n-octanol/water partition coefficient is discussed. The results show that its magnitude is the same as that of values in the literature.

Partition Coefficient of Proteins of Different Surface Hydrophobicity in Poly (ethylene glycol)-Dextran Aqueous Two Phase System (Poly(ethylene glycol)-Dextran 수용액 2상계에서 단백질들의 소수성에 따른 분획계수)

  • Lee, Sam-Pin;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.19 no.2
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    • pp.140-145
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    • 1987
  • The partition coefficient of the proteins of known effective hydrophobicity was determined in a poly (ethylene glycol)-dextran aqueous two-phase system. The changes in the partition coefficient was also determined when a fraction of PEG-palmitate (PEG-P) was added to the system. The partition coefficient of the proteins increased as the concentrations of PEG and dextran increased at a constant phase volume ration irrespective of the effective hydrophobicity of the proteins. When small amounts of PEG-P were added to the PEG phase, the partition coefficients of BSA and ${\beta}-lactoglobulin$, which had relative hydrophobicity (RI) of 700 and 120, respectively, increased more than ten-fold, whereas ovalbumin whose RI was 5 showed little change. The drastic increases m the partition coefficient were observed by the addition of PEG-P in 2% level to the PEG system. Addition of PEG-P over 5% level resulted in a slight further increase in the partition coefficient of all proteins tested.

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Feasibility of Fibrous Solid Phase Extraction to Alkylphenols Analysis (섬유상 고상 추출물질을 이용한 알킬페놀 화합물 분석 가능성)

  • Jung, Yong Jun
    • Journal of Korean Society on Water Environment
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    • v.27 no.3
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    • pp.329-333
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    • 2011
  • p-phenylene-2,5-benzobisoxazole (PBO; Zylon$(R)$) fibers as an adsorbent were employed for solid phase extraction of aqueous alkylphenols. The removal ratios for 10 kinds of alkylphenols at initial concentration of $100{\mu}gL^{-1}$ were in the range of 16.8-96.3% and the removals increased with the increase of the phase ratio (fiber weight/solution volume). The plots of the logarithm of partition coefficient (log K) were correlated with the logarithm of the n-octanol/water partition coefficient (log P). The adsorbed alkylphenols were completely desorbed with the mixture of acetonitrile and dichloromethane.

Formation of PEG/Dextran Aqueous Two-Phase System for Starch Hydrolysis Using $\alpha$-Amylase ($\alpha$-Amylase로 전분 가수분해를 위한 PEG/Dextran 수성 2상계 구성)

  • 박병춘;임동준
    • Microbiology and Biotechnology Letters
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    • v.20 no.2
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    • pp.190-195
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    • 1992
  • In the polyethylene glycol/dextran aqueous two-phase systems, volume ratio was increased and partition coefficient was decreased with the increase of potyethylene glycol molecular weight and concentration. However the volume ratio was decreased and the partition coefficient was increased with the increase of dextran molecular weight. On the other hand, the volume ratio and the partition coefficient were decreased with the increase of dextran concentration. Continuous enzymatic hydrolysis of soluble starch with $\alpha$-amylase which was produced by Bacillus amyloliquefaciens IF0 14141 was investigated in polyethylene glycol/dextran aqueous two-phase systems. Nonreacted soluble starch and $\alpha$-amylase were reused in these systems. $\alpha$-Amylase activity was maintained more than 100 hrs by recycling of $\alpha$-amylase from bottom of settler to reactor.

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Organic Pollutant Transport in Unsaturated Porous Media by Atmospheric Breathing Processes( I ) - Partition Coefficient -

  • Ja-Kong;Lim, Jae-Shin;Do, Nam-Young
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.50-53
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    • 1996
  • This paper reports the experimental results for the determination of the overall partition coefficient of VOCs in unsaturated soil, A chromatographic method was used for the determination of gaseous partition coefficients to natural soil under various water content conditions. The equilibrium vapor pressure of water over saturated salt solution was used to fix the relative humidity of the air and control the water content of the soil systems. The transport behavior was studied for dichloromethane, trichloroethane and dichlorobenzene pollutants, with log octanol-water partition coefficients(log $K_{ow}$ ) which range from 1.25 to 3.39, or water to soil partitioning which varies by 135 times; water solubility constants which vary by 3 times; and vapor pressures which range from 1 to 362 torr. Water content of the soil had a pronounced effect on the effective partition coefficient(between gas and soil + water stationary phase) as well as on the effective dispersion coefficient.

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Nalidixic Acid Prodrugs: Amides from amino acid ester and nalidixic acid

  • Taori, Ashish;Nema, Rajesh;Kohli, D.V.;Uppadhyay, R.K.
    • Archives of Pharmacal Research
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    • v.14 no.1
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    • pp.48-51
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    • 1991
  • Amides from amino acid ester and nalidixic acid were synthesized. The solubility characteristics and partition coefficient of the compounds were studied. The hydrolysis of the compounds was studied in the simulated gastric fluid and simulated intestinal fluid. Some compounds showed better antibacterial activity than nalidixic acid.

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Large-Scale Purification of Protease Produced by Bacillus sp. from Meju by Consecutive Polyethylene Glycol/Potassium Phosphate Buffer Aqueous Two-Phase System

  • Cho, Seong-Jun;Kim, Chan-Hwa;Yim, Moo-Hyun;Lee, Cherl-Ho
    • Journal of Microbiology and Biotechnology
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    • v.9 no.4
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    • pp.498-503
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    • 1999
  • Protease produced from Bacillus sp. FSE-68 was isolated from Meju, a Korean fermented soybean starter, and was purified by a two-consecutive aqueous two-phase system. The change of partition coefficient (K) in the polyethylene glycol (PEG)/potassium phosphate buffer (PPB) aqueous two-phase system was measured at different pHs (6.0- 9.2), PPB concentrations (8-12%), and temperatures (4 and $20^{\circ}C$). As the PPB concentration in the aqueous two-phase system increased, the protease concentration in the top phase (PEG-rich phase) increased, thereby enhancing the partition coefficient. The minimum partition coefficient of the protease was achieved at pH 7.0, whereas that of the total protein was at pH 6.0. The biggest difference in partition coefficients of total protein and protease occurred at pH 6.0. It was interesting to note that the partition coefficient of protease decreased as the temperature increased. The optimum condition of the primary aqueous two-phase extraction of Bacillus sp. FSE-68 was pH 6.0, 14% (w/w) PPB, and 16% (w/w) PEG at $4^{\circ}C$, and the crude enzyme concentration in this system was 50% (w/w). The protease, which was concentrated in the top phase, was further mixed with 15% (w/w) PPB (pH 7.0) in the ratio of 1:1 at $20^{\circ}C$ to elute the bottom phase (PPB-rich phase). Using these steps, the purification fold achieved was 9.2 with a 44.7% yield.

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