• Journal of Pharmaceutical Investigation
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• v.21 no.3
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• pp.161-170
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• 1991

The storage stabilities of immunoliposomes incorporated with variable amounts of ganglioside $G_{M1}$ were investigated as a function of time. temperature. and composition by observing absorbance of visible light and calcein release. In the column chromatographe, the layer of unsaturated PE(dioleoylphosphatidylethanolamine : DOPE). unable to form stable liposomes at physiological temperature and pH, were formed when palmitoyl-immunoglobulin G(IgG) $(2.5{\times}10^{-4}\;mol/DOPE\;mol)$ added. The incorporation of ganglioside $G_{M1}$ into immunoliposome. enhanced the stabilities of bilayers during the extended period of storage. The turbidities of immunoliposomes coated with ganglioside $G_{M1}$ exhibited the maximum near 20 mol% $G_{M1}/DOPE$ mol. probably because of the disturbance of the bilayer characteristics, i.e., layer transition or reorientation of interaction sites. At low temperature. the higher stability was achieved than at elevated temperatures. After one week of storage. the redispersed liposomal solutions at lower temperatures maintained the original elution patterns in chromatography but broader distribution at elevated temperatures. During the storage, it is suggested the aggregation is the more dominant phenomena for liposomes kept at $5^{\circ}C$ than the fusion. while he fusion is at elevated temperatures.

• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.329-334
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• 2006

Cationic liposome has been studied as one of the most promising non-viral gene delivery systems. In this report, we describe a new synthesized cholesterolic cationic lipid (2-aminoethylcarbamate-cholesterol) and dioleylphosphatidylethanolamine (DOPE) improve the cellular uptake properties of antisense ODNs, as well as plasmid DNA with low toxicity. This formulation of cholesterolic cationic lipid termed Chol-E, efficiently transfects ODNs and plasmids into many cell types in the presense or absence of 10% serum in the medium.

• Journal of Microbiology and Biotechnology
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• v.22 no.6
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• pp.866-871
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• 2012

A novel cholesterol-based cationic lipid containing a tri-2-hydroxyethylamine head group and ether linker (Chol-THEA) was synthesized and examined as a potent gene delivery vehicle. In the preparation of cationic liposome, the addition of DOPE as helper lipid significantly increased the transfection efficiency. To find the optimum transfection efficiency, we screened various weight ratios of DOPE and liposome/DNA (N/P). The best transfection efficiency was found at the Chol-THEA:DOPE weight ratio of 1:1 and N/P weight ratio of 10~15. Most of the plasmid DNA was retarded by this liposome at the optimum N/P weight ratio of 10. The transfection efficiency of Chol-THEA liposome was compared with DOTAP, Lipofectamine, and DMRIE-C using the luciferase assay and GFP expression. Chol-THEA liposome with low toxicity had better or similar potency of gene delivery compared with commercial liposomes in COS-7, Huh-7, and MCF-7 cells. Therefore, Chol-THEA could be a useful non-viral vector for gene delivery.

• Membrane Journal
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• v.32 no.2
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• pp.109-115
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• 2022

In this work, the effect of nonwoven support during fabrication of flat sheet membranes via nonsolvent-induced phase separation, was investigated in detail. It was found that dope solutions with low viscosity tend to penetrate through the nonwoven support during phase inversion, resulting in nonhomogeneous membranes. A simple soaking treatment of nonwoven support prevented such unwanted dope penetration, and resulted in membranes with higher water and solvent permeance performance. The dope penetration through nonwoven was more prominent in solutions with low viscosity, and the nonwoven soaking treatment not effective in solutions with high viscosity.

• The International Journal of Costume Culture
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• v.8 no.2
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• pp.124-131
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• 2005

This study focused on the change of skin temperature by the emissivity and emission power of far-infrared for conformant far infrared effect to naked eyes. The study method is to manufacture the bra pad by each concentration on far-infrared materials of illite powder $(K,H_3O)AI_2(Si,Al)_4O_{10}(H_2O,OH)_2)$, liquid alumina ($Al_2O_3$), the extracted liquid from 29 kind of medical plants, then, measured change of skin temperature. Result are as follows. Far-infrared were emitted each $90.2\%,\;90.1\%,\;89.7\%$ from the illite powder, liquid alumina, extracted liquid from medical plants. When the testee weared the bra pad, the temperature of coated bra pad was $0.5^{\circ}C$ higher than the non finished bra pad. Washing fastness on far-infrared finishing was better dope addition method than coating method.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.57-62
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• 2002

Cationic liposomes complexed with DNA have been extensively utilized for the delivery of reporter or therapeutic genes both in culture and in vivo. We investigated and determined the optimum conditions of a cationic liposome, composed of dimethyldioctadecy-lammonium bromide (DDAB) and dioleoyl phosphati-dylethanolamine UOPE), mediated a reporter plasmid expressing luciferase into insect cell lines (Sf-21 and Bm-N) and silkworm larvae. Together the data demonstrated that Bombyx mori nuclear polyhedrosis virus (BmNPV) genomic DNA (128 kb) was successfully transfected into Bm-5 cells using this liposome. These results suggest that DDAB/DOPE liposome will be useful as delivery agents for gene transfer to insect cells both in vitro and in vivo.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.09a
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• pp.73-85
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• 1995

The asymmetric hollow fiber membranes were prepared by the wet spining of polyetherimide dope solution and the effect of hollow fiber structures on the permeation characteristics of carbon dioxide and nitrogen gases through these membrane were investigated. As the concentration of the $\gamma$-butyrolactone (GBL) in dope solution, acting as a swelling agent was increased, the structure of hollow fiber was changed from the finger to sponge type. The permeabilities of gases (CO$_{2}$, N$_{2}$) through these membrane were measured over the wide range of pressure under different temperature. The effect of water vapor on the permeabilities of gases was also investigated. The measured permeabilities showed the different characteristics depending on the structure of membranes. It was found that the flow through the pores were dominant over the polymers matrix. Blocking effect by water vapor in the pores of skin layer greatly improved the ideal separation factor of carbon dioxide/nitrogen.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.04a
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• pp.45-45
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• 1995

Filtration, one of the most important process in the various industrials, is defined as the separation of two or more compounds from a fluid by passing the mixture refers to the separation of solid, immisible particles from liquid or gaseous mixture. Membrane filtration which is a type of filtration extends it's application further to include the separation, concentration, and filtration. The main objective of this investigation is the preparation of organic solvents-resistant polyimide membranes by using phase inversion technique and their application as a UF membrane. Specially, the dope solution was prepared from the newly developed method. The newly developed method is that the dope solution was directly prepared from the polyimide solution which was prepared by the modified one-step polymerization. The effects of the parameters for membrane preparation such as the casting solution composition and the casting conditions were investigated and the performance and chemical stabfiity of membrane are going to be tested.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.07a
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• pp.83-86
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• 1999

The imidization effect of a poly (amic acid) dope solution on membrane formation has been investigated. Poly (amic acid) solution in S-methyl-2-pyrrolidione hs been thermally imidized at $120^{\circ}C$ with different curing time and its degree of imidization was determined by infrared spectroscopy. The solution properties have been studied as a function of concentration and curing time by dynamic light scattering. The quality of a solvent was changed from good to poor with increasing imidization of poly(amic acid).The reduced polymer-solvent interaction diminishes the membrane formation time. The morphology of a membrane was able to be controlled by the characteristics of dope solution.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.645-649
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• 1998

In order to develop pH-sensitive liposomes that are stable in plasma, liposomes containing membrane-spanning bipolar amphiphiles as protonatable components were studied. Sonicated small unilamellar liposomes composed of dioleoylphosphatidylethanol amine (DOPE), dioleoylphosphatidylcholine (DOPC) and bis(6-hemisuccinyloxyhexyl) fumarate (BHF) in a 3 : 1 : 1 molar ratio are stable at neutral pH, but destabilized at weakly acidic pH with 50% leakage of entrapped materials at about pH 5.5. The liposomes are relatively stable in plasma such that only a few percent entrapped calcein was released in 50% plasma within 1.5 h incubation at 37 ℃, while about 10% entrapped calcein was released from sonicated liposomes composed of DOPE, DOPC, and oleic acid (OA) in a 3 : 1 : 1 molar ratio under the identical conditions. The aqueous contents mixing and lipid components mixing experiments suggest that the protonation of BHF may induce fusion between the liposomes, followed by the release of the entrapped materials.