• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.55-58
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• 2004

Cell separation from peripheral blood was investigated using surface-modified polyurethane (PU) membranes with different functional groups. Both red blood cells and platelets could pass through unmodified PU and PU-SO$_3$H membranes, while the red blood cells preferentially passed through PU-N(C$_2$H$_{5}$ )$_2$ and PU-NHC$_2$H$_4$OH membranes. The permeation ratio of T and B cells was less than 25% for the surface-modified and unmodified PU membranes. CD34$^{+}$ cells have been recognized as various kinds of stem cells including hematopoietic and mesenchymal stem cells. The adhesiveness of CD34$^{+}$ cells on the PU membranes was found to be higher than that of red blood cells, platelets, T cells or B cells. Overall, the adhesiveness of blood cells on the PU membranes increased in the following order: red blood cells $\leq$ platelets ＜ T cells $\leq$ B cells ＜ CD34$^{+}$ cells. Treatment of PU-COOH membranes with a human albumin solution to detach adhered blood cells, allowed recovery of mainly CD34$^{+}$ cells in the permeate, while both red blood cells and platelets could be isolated in the permeate using unmodified PU membranes. The PU membranes showed different permeation and recovery ratios of specific cells depending on the functional groups attached to the membranes.mbranes.

• 한국수소및신에너지학회논문집
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• 제27권5호
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• pp.478-484
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• 2016

Polyether ether ketone (PEEK) composite membranes have been intensively investigated for polymer electrolyte membrane water electrolysis (PEMWE). Covalently linked (CL) sulfonated polyether ether ketone (SPEEK) and cellulose polymer composite membranes were prepared and characterized. Polyether ether ketone (PEEK) and cellulose were sulfonated and then were covalently linked by 1,4-diiodobutane to produce covalently linked SPEEK and cellulose polymer composite membranes. The composite membranes showed better thermostability and electrochemical properties than SPEEK. The membranes were prepared by sol-gel casting method. CL-SPEEK/Cellulose composite membrane featured 0.2453 S/cm of proton conductivity at $80^{\circ}C$ which was better than that of Nafion.

• Bulletin of the Korean Chemical Society
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• 제14권1호
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• pp.123-127
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• 1993

New lipophilic Crown-4 compounds of 16-membered rings containing furan (neutral carrier,I), tetrahydrofuran (neutral carrier,II) and lithium complex of the latter (neutral carrier,III) have been synthesized and tested as the active sensors for lithium ion in poly(vinyl chloride) (PVC) membrane electrode, in the presence and absence of an anion excluder, tetrakis(4-chloro-phenyl)borate (KTClPB), 2-nitrophenyl phenyl ether (NPPE), tris(2-ethylhexyl)phosphate (TEHP), o-nitrophenyl octyl ether (NPOE), dioctyl adipate (DOA), bis(2-ethylhexyl)adipate (BEHA), di-n-octylphenyl phosphonate (DOPP) were used as plasticizing solvent mediators. The electrode response function had a nearly Nernstian slope of 54-61 mV per decade (25$^{\circ}$C) within the concentration range of $10^{-1}-10^{-4}$ M LiCl and the detection limits for all electrodes were ca. $5{\times}10^{-4}$ M. The response time of the electrode was faster at the higher lithium concentration and the response of the electrode was stable for longer than 6 months. The sensor membranes exhibit improved response times and increased lifetimes as compared to the system described earlier.

• 통합자연과학논문집
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• 제15권4호
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• pp.137-144
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• 2022

This paper presents the effect of the supramolecular complex of GA (Glycyrrhizic acid) and Mt(menthol) and GA: Mt (4: 1) obtained on their basis can restore functional dysfunction of the liver mitochondria in alloxan diabetes, ie, inhibit lipid peroxidation. The hypoglycemic activity and mitochondrial membrane stabilizing properties of the supramolecular compound GA: Mt (4: 1) in alloxan diabetes were more pronounced than those of menthol, GA and its GK: Mt (2: 1) and GA: Mt (9: 1) compounds. According to the results obtained, the concentration of GA did not affect the peroxidation of lipid membranes of the liver mitochondria. However, a concentration of 15 μM of GA was found to reduce LPO (lipid peroxidation) formed by the effect of Fe²+ / ascorbate on the mitochondrial membrane by 58.0 ± 5.0% relative to control. The inhibitory effect of GA and its supramolecular compounds in different proportions with menthol on the peroxidation of lipids in rat heart and brain tissue has been studied

• Molecules and Cells
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• 제26권6호
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• pp.517-529
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• 2008

Porosomes are supramolecular, lipoprotein structures at the cell plasma membrane, where membrane-bound secretory vesicles transiently dock and fuse to release inravesicular contents to the outside during cell secretion. The mouth of the porosome opening to the outside, range in size from 150 nm in diameter in acinar cells of the exocrine pancreas, to 12 nm in neurons, which dilates during cell secretion, returning to its resting size following completion of the process. In the past decade, the composition of the porosome, its structure and dynamics at nm resolution and in real time, and its functional reconstitution into artificial lipid membrane, have all been elucidated. In this mini review, the discovery of the porosome, its structure, function, isolation, chemistry, and reconstitution into lipid membrane, the molecular mechanism of secretory vesicle swelling and fusion at the base of porosomes, and how this new information provides a paradigm shift in our understanding of cell secretion, is discussed.

• 폴리머
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• 제36권2호
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• pp.155-162
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• 2012

전기방사 방법으로 sulfonated poly(ether ether ketone) (SPEEK) 나노섬유를 제조하고, 압축성형법으로 고분자 전해질막 연료전지(polymer electrolyte membrane fuel cell, PEMFC)용 나노섬유막을 제조하였다. SPEEK의 최대 설폰화율은 95% 이었고 초기 열분해 온도는 약 $280^{\circ}C$로 PEEK 보다 낮았으며 접촉각은 설폰화도가 증가함에 따라 감소하였다. 전기방사 나노섬유의 최적 인가전압, 유속, 방사거리(tip to collector distance, TCD) 및 농도는 각각 22 kV, 0.3 mL/hr, 5 cm, 23 wt% 이었고 평균 섬유직경은 47.6 nm 이었다. 한편, SPEEK 이온교환 나노섬유막의 함수율 및 이온교환용량은 설폰화 시간과 설폰화제 함량이 증가함에 따라 증가하였으며 최적값은 각각 20%, 2.03 meq/g으로 Nafion 117 보다 우수하였다. 막의 전기저항은 설폰화 시간이 증가함에 따라 감소하였고 그 값은 0.58~0.06 ${\Omega}{\cdot}cm^2$로 측정되었다. 또한 막의 수소이온전도도는 설폰화 시간이 증가함에 따라 증가하였으며 최대 0.099 S/cm로 Nafion 117 보다 우수하였다.

• 대한화학회지
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• 제44권2호
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• pp.115-119
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• 2000

새로운 캘릭스[4] 크라운 화합물을 이온 선택성 물질로 사용하고 지지체로 PVC(poly(vinylchloride)), 가소제로 DOS(Dioctyl sebacate}를 사용하여 막전극을 제작 하였다. 제작한 막전극을 지시전극으로 사용하여 알칼리, 알칼리토금속 이온 그리고 전이금속 이온에 대하여 각각의 감응전위를 측정한 결과, $10^{-6}{\sim}10^{-2}M\;Pb(NO_3)_2$ 용액에서 $Pb^{2+}$이온의 감응전위가 이론적인 Nernstian식 기울기에 가까운 27.0 mV/decade로 직선성이 잘 성립하는 감응전위를 나타내었다. $Pb^{2+}$ 이온 농도변화에 따른 막의 감응시간은 $t_{90}$=10 sec 이었고, 막의 사용기간은 2개월 정도이다. 또한 pH 영향을 조사해 본 결과 pH $2.0{\sim}12$ 범위에서 감응전위 값이 일정하게 유지되었다.

• 한국수소및신에너지학회논문집
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• 제26권3호
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• pp.212-220
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• 2015

The engineering plastic of sulfonated polyether ether ketone (SPEEK) as a polymer matrix has been developed in this lab to replace Nafion, solid polymer electrolytes of perfluorosulfonic acid membrane which has several flaws such as high cost, and limited operational temperature above $80^{\circ}C$. The SPEEK was prepared in the sulfonation reaction of polyether ether ketone (PEEK). The organic-inorganic blended composite membranes were prepared by sol-gel casting method with loading the highly dispersed ceria and cesium-substituted tungstosilicic acid (Cs-TSiA) with cross-linking agent contents of 0.01 mL. In conclusion, CL-SPEEK/Cs-TSiA/ceria 1% membrane showed the optimum results such as 0.1882 S/cm of proton conductivity at $80^{\circ}C$, and 99.61 MPa of tensile strength which were better than Nafion 117 membrane.

• Journal of Applied Biological Chemistry
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• 제42권2호
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• pp.85-91
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• 1999

The incubation study was conducted under aerobic and anaerobic conditions to study the release of the kinetically labile forms (i. e. chelating ion or anion forms) of Cd, Cu and Zn in sludge-untreated soil ("Control"), sludge 50 and $100dry\;Mg\;ha^{-1}$ treated soils ("Soil-Sludge mixtures"), and sewage sludge ("Sludge"). The chelating ion and anion exchange membranes were embedded into the samples and incubated for 16 weeks under aerobic and anaerobic condition. The total amounts of chelating ion or anionic forms of Cd were too little to be measured during both aerobic and anaerobic incubation. On the other hand, the total amounts of chelating ion or anionic forms of Cu and Zn slightly increased throughout the incubation period under both incubation conditions. For "Control" and "Soil-Sludge mixtures" treatments, the total amounts of Cu and Zn in chelating ion and anion exchange membrane were little difference between aerobic and anaerobic condition, and the total amounts of chelating ion form of Cu and Zn were not different from the those of anionic form of Cu and Zn. However, for "Sludge" treatment, the total amounts of Cu and Zn in anion and chelating ion exchange membrane were greater under aerobic condition than under anaerobic condition, and the total amounts of chelating ion form of Cu and Zn were greater than those of anion form of Cu and Zn under both incubation conditions.

• 대한화학회지
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• 제28권3호
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• pp.163-169
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• 1984

칼륨이온이 dibenzo-18-crown-6(DBC)에 의해 $H_2O-CHl_3-H_2O$액체막을 통하여 운반되는 속도를 10가지 칼륨염의 농도를 변화시키면서 $25^{\circ}C$에서 측정하였다. 운반속도는 농도와 음이온의 특성에 크게 의존했으며 농도효과로 부터 피크르산칼륨의 경우에는 이온쌍 형성으로 인하여 1.0 ${\times}10^{-3}$M을 전후하여 각기 다른 양상을 보였다. 이온의 운반과정은 다단계 착물반응 및 확산과정에 의한 것으로 운반 메카니즘을 체계화하기 위해 비균질성 액체막의 각상에서 갖는 화학종의 에너지 장벽모델을 제시하였다. 또한 이를 음이온의 수화자유 에너지와의 관계를 비교함으로써 새로이 7단계 운반과정을 제시하고 그 운반 메카니즘을 고찰하였다.