• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.149-152
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• 2000

The effects of selected co-surfactants on diesel removal from sandy soil were studied to increase diesel recovery from the soil by the surfactant-enhanced remediation of diesel-contaminated soil. The capability of co-surfactant for enhancing removal efficiency can be related with the interaction between its structural character and the structural peculiarity of nonionic surfactant. In the case of Tween 80, hexanol showed the great improvement in diesel recovery. Efficiency of diesel recovery decreased as hydrocarbon chain length of cosurfactant decreased. Higher content of hexanol further increased diesel recovery, but there was no significant improvement in the case of butanol and pentanol.

• Journal of Pharmaceutical Investigation
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• v.38 no.1
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• pp.45-50
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• 2008

5-Fluorouracil (5-FU) is an antimetabolic of the pyrimidine derivatives that is used in chemotherapy for the treatment of several types of cancer. 5-FU have poor oral absorption and short biological half-time and strong side effects. Microneedle introduced to find a solution of problems. Microneedle device with roll was manufactured for transdermal delivery of various drugs. 5-FU was mixed in non-ionic surfactant such as tween 20 and tween 80. Camscope was used to analysis the permeation magnitude of treated skin by microneedle and trypan blue staining. The 5-FU solution with surfactant measured by ZETA-potential analysis system for stability of solution. The skin permeation rate of 5-FU determined by HPLC. We confirmed that cross treated skin was dyed more deeply than parallel treated skin through trypan blue staining. The results indicate that skin permeation rate of 5-FU was increased with the treatment types and treatment times.

• Journal of Pharmaceutical Investigation
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• v.34 no.2
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• pp.125-130
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• 2004

Paclitaxel is an effective antineoplastic drug for various cancers especially ovarian and breast cancer. This study is to find the optimum condition for the preparation of nanoemulsions and to improve the stability and loading amount of paclitaxel in nanoemulsions. Nanoemulsions were prepared by modified spontaneous emulsification solvent diffusion method. It was composed of phosphatidylcholine:cholesterol:1,2-Distearoyl-sn-Glycero-3-Phosphoethanolamine-N-[Metoxy (Polyethylene glycol)-2000]:paclitaxel at a weight ratio of 5:3:1:1 and the Tween 80 as a surfactant. The particle size and the shape of nanoemulsions were measured by particle analyzer and SEM, respectively. The loading amount of paclitaxel in nanoemulsion was measured by UV-visible spectroscopy at 227 nm. The particle sizes were $80{\sim}120\;nm$ and the loading efficiency of paclitaxel was $8{\sim}39%$. The optimum conditions for the preparation of nanoemulsions were 8% w/w phospholipid, 16% w/v Tween 80 and 2% w/w paclitaxel, respectively.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.77-86
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• 1999

Partitioning of two hydrophobic organic compounds (HOCs), phenanthrene and naphthalene, to kaolinite and sorbed surfactants was studied to evaluate the feasibility of surfactant-enhanced remediation (SER) of contaminated subsurface systems. Sorbed surfactant partition coefficients. $K_ss$, showed a strong dependence on the surfactant sorption isotherms at low sorbed surfactant levels $K_ss$ values were at their highest and then decreased with increasing surfactant sorption densities. $K_ss$ values for SDS were always larger than corresponding $K_mic$values. For Tween 80, however. $K_ss$ values $K_mic$ were higher than $K_mic$ values only at the lower sorbed surfactant densities. HOC distribution between immobile and mobile phases varied with surfactant dose distribution coefficients increased initially with increasing surfactant concentrations and then decreased at higher doses. This observation shows directly the competition between sorbed and micellar surfactants for HOC partitioning. Overall results of this study demonstrate that surfactant sorption to the solid phase can lead to increases in HOC retardation in some SER applications. Therefore, before an SER process is selected, appropriate consideration of surfactant sorption and HOC partitioning to immobile versus mobile phases pertinent to a specific subsurface system must be contemplated.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1135-1139
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• 2005

Psychrotrophic phenanthrene-degrading bacteria were identified in the sediment samples collected from Lake Baikal, Russia. Among 70 phenanthrene-degrading isolates, the seven that had the highest phenanthrene-degradation rates were identified by 16S rDNA sequencing. Isolate P25, identified as the Gram-positive rod-shaped organism Rhodococcus erythropolis, had the highest growth and degradation rate at $15^{\circ}C$. It could remove $26.0\%$ of 100 mg $1^{-1}$ phenanthrene in 20 days at $15^{\circ}C$, and degradation was less at $5^{\circ}C\;and\;25^{\circ}C$. The addition of surfactants to enhance degradation was tested. Brij 30 and Triton X-100 inhibited degradation at all surfactant concentrations tested, but Tween 80 stimulated phenanthrene degradation, especially at low concentrations. When $20{\times}$ CMC (critical micelle concentration) of Tween 80 was added, $38.0\%$ of 100 mg $1^{-1}$ phenanthrene was degraded in 12 days at $15^{\circ}C$. This psychrotrophic phenanthrene-degrading bacterium is a candidate for use in bioremediation of polycyclic hydrocarbon contamination in low temperature environments.

• KSBB Journal
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• v.22 no.3
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• pp.146-150
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• 2007

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] microspheres were prepared using solvent evaporation technique. P(3HB-co-4HB) with 3.9 mol% 4HB was synthesized by fed-batch culture of Ralstonia eutropha. The effects of concentration and type of surfactant (Tween 80, sodium dodecylsulfate, and polyvinyl alcohol), addition of dispersion stabilizer (Acacia), concentration of polymer and model drug (bovine serum albumin) on particle size of the microspheres and their in vitro drug release characteristics were investigated. The average particle size of the microspheres decreased with the addition of dispersion stabilizer and increased with the concentration of surfactant, drug and polymer. Amount of drug release increased with decreasing particle size of the microspheres.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.3 s.162
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• pp.433-439
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• 2007

The effects of nonionic surfactants on detergency and water wetting/retention properties of soiled cotton cloths were reported. Two different soiled cloths were used. soiled cotton cloth 1 was made in the lab. with carbon black, tripalmitin, n-dodecane & palmitic acid on Korea Apparel Testing & Research Institute(KATRI) cotton testcloth and soiled cotton cloth 2(EMPA 101) was purchased from Testfabrics, Inc., USA. The following nonionic surfactants; l.e., Span 20, Tween 20, 40, 60, 80, 21, 61, 81, 65, & 85, were used in the study. The water retention ratio(W/H) values of soiled cotton cloths were decreased, whereas the water contact angle values of soiled cloth were not changed markedly compared with those of unsoiled testcloths. The wetting and water retention of soiled cotton cloth 1 was improved with addition of nonoinic surfactants. The surfactants which have more hydrophilic characterictics or unsaturated hydrophobe tails were effective in improving wetting and water retention properties of soiled cotton cloth 1. The water contact angle values of soiled cotton cloths were extremely low with Span 20, presumably due to the high adsorption density or the surfactant. The detergency of soiled cloths were low in Span 20 and high in Tween 20, 40, 60 & 80 0.1g/dl surfactant solutions. Nonionic surfactants having higher ethylene oxide contents resulted in better detergency. In the range studied, the wetting and water retention of soiled cotton cloths did not show any particular relation to the detergency, whereas the surfactant characteristics, especially HLB values, influenced the detergency of soiled cotton cloths.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.191-195
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• 1999

Bioconversion of fumarate to succinate by Enterococcus sp. RKY1 was enhanced when Tween surfactant, organic solvent, and vegetable oil were added to the fermentation medium. The maximum amount of succinate produced was 80.4 g/l after a 24 h incubation when Tween 80 was added to the culture to a final concentration of 0.1 g/l. Triton X-l00 was observed to damage the enzymes and inhibit the formation of succinate. The addition of 10 ml/l acetone increased the production of succinate by 110%. Vegetable oils used were found to be effective for succinate production as well as for the cell growth. Similar productivity increases were obtained with corn oil and Tween 80 plus biotin with the total productivity being 3.6 g/l/h, and 3.5 g/l/h, respectively, which was approximately 25% greater than that of the control. Therefore, these results indicate that com oil can be considered the most appropriate agent for the production of succinate where succinic acid was primarily used in the production of food, medicine, and cosmetics.

• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1252-1256
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• 2009

A simple, selective and sensitive fluorescence quenching method was developed to the determination Cr(VI). The method is based on the oxidation of $I^-\;to\;{{I_3}^-}$ by Cr(VI) in sulfuric acid solution followed by immediate formation of ion association compound between I3 − and rhodamine 6G in Tween-80 micellar media at room temperature. The influence of several surfactants on rhodamine 6G fluorescence signal was studied; particular attention was paid in the aggregation behavior of rhodamine 6G–Tween-80 system. The experimental parameters (e.g., type of surfactant, reagent concentration) were studied and the optimal conditions were established. The linear calibration graph was obtained in the range 2.0 - 100.0 ng m$L^{-1}$ Cr(VI). The detection limit of the method was 0.37 ng m$L^{-1}$. The relative standard deviation (R.S.D.) is less than 5% (n = 5). The efficiency of the method for the determination of Cr(VI) in the presence of Cr(III) in the sample was investigated. The method was applied successfully to the determination of Cr(VI) and total Cr in water, and liver tissue samples.

• Polymer(Korea)
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• v.38 no.6
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• pp.744-751
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• 2014

Electrospinning was used to load curcumin (a natural compound that has antiinflammatory properties) into zein nanofibers. An emulsifier, Tween 80, was combined with curcumin in the zein nanofibers. The morphology of the curcumin-loaded zein nanofibers (CLZNFs) was observed using field emission scanning electron microscopy. Investigation of curcumin released from the zein nanofibers into phosphate buffer saline at pH 7 indicated that the Tween 80 had increased the amount of curcumin released from the CLZNFs. The antibacterial activity of the CLZNFs against Staphylococcus aureus (S. aureus) was determined by measuring the optical density of bacterial solutions containing CLZNFs. The zein nanofibers fabricated with 10 wt% surfactant and 1.6 wt% curcumin showed high (i.e., 83%) efficiency in inhibiting the growth of S. aureus in the solution incubated for 21 h. These results suggest that the electrospun CLZNFs show potential application as antibacterial nonwoven mats.