• Journal of Photoscience
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• 제6권4호
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• pp.159-163
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• 1999

The fluorescence quenching of 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole (PBD) and 1,4-di-[2-(5-phenyloxazolyl)]-benzene (POPOP) by aniline has been carried out in different solvent mixtures of dioxane and acetonitrile at room temperature. The quenching is found to be appreciable and a positive deviation from linearity was observed in the Stern-Volmer plot in all the solvent mixtures. Various rate constants for the quenching processes have been determined using a modified Stern-Volmer equation. From the positive deviations of linear Stern-Volmer plots and the dependence of rate constants on the polarity of the solvents, it has been concluded that both static and dynamic quenching processes are responsible for the observed positive deviation in the Stern-Volmer plot.

• 한국염색가공학회지
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• 제27권4호
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• pp.340-344
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• 2015

The interaction between curcumin(1,7-bis[4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione) and ethylamines was studied in DMSO:$H_2O$(5:1, v/v) using absorption and fluorescence measurements. The association constant, $K_{ass}$, and the Stern-Volmer constants were calculated by the Benesi-Hildebrand and Stern-Volmer equation, respectively. Curcumin displayed marked UV-Vis absorption changes and highly responsive fluorescence quenching in the presence of ethylamine and the quenching ability was enhanced almost linearly with the concentration of ethylamines. The apparent Stern-Volmer constant measured for the ethylamine-curcumin system was about 1000-fold greater than that of the triethylamine-curcumin system, indicating considerably greater quenching efficiency of ethylamines.

• Archives of Pharmacal Research
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• 제8권4호
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• pp.205-211
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• 1985

The distribution of local anesthetics between the hydrocarbone interior and surface area of the lipid bilayer of liposomal membrane was calculated employeg fluorescence probe technique. The quenching of fluorescence probe technique. The quenching of fluorescence probe technique. The quenching of fluorescence of 12-(9-anthroyl) stearic acid and N-octadecyl naphthyl-2-amini-6-sulfonic acid by the local anesthetics in liposomal system was used to calculate the distribution. The Stern-Volmer equation was modified and employed for this calculation. The results showed that procaine hydrocloride and benzocaine were mainly distributed on the surface area of the lipid bilayer of the liposoal membrane, while tetracaine hydrochloride penetrated effectively into the hydrocarbon interior and showed even distribution in the lipid bilayer.

• 대한약리학회지
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• 제31권3호
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• pp.271-278
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• 1995

Barbiturates의 분자적 약리학적 작용기전 연구에 기초자료를 제공키 위하여 본연구를 수행하였다. 분자적 약리작용 기전 연구에서는 무엇보다도 선행되어야 하는 것이 barbiturates가 신경세포막에서 어느 부위에 주로 분포되는가를 알아내는 데에 있다. 쥐(Rat)의 뇌로부터 분리한 synaptosomal plasma membrane vesicles (RSPMV)를 분리한 후 이 RSPMV 외측 단층(outer monolayer)의 소수성 부위와 친수성 부위에 barbiturates가 분포되는 경향을 형광 probe 법으로 검색하였다. 세포막 외측 단층의 친수성 부위에 분포되는 형광 probe N-octadecylnaphthyl-2-amino-6-sulfonic acid (ONS)와 소수성 부위에 분포되는 형광 probe12-(9-anthroyloxy)stearic acid (AS)를 각각 봉입한 후 형광소광법으로 barbiturates의 분포를 측정한 결과는 다음과 같다. 1) 대부분의 barbiturates가 RSPMV 외측 단층의 친수성 부위(표면)에 분포되고 소수성 부위 (hydrophobic region)에 극히 소량만이 분포된다는 것을 확인하였다. 2) 마취효과를 크게 일으키는 barbiturates일수록 소수성 부위에 분포되는 양이 증가하였다. barbiturates 종류에 따른 RSPMV 외측 단층 소수성 부위에의 분포 크기는 thiopental sodium > pentobarbital > hexobarbital > amobarbital > phenobarbital의 순위였다.

• BMB Reports
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• 제33권3호
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• pp.221-227
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• 2000

The distribution of barbiturates in the model membranes of total lipids (SPMVTL) and total phospholipids (SPMVPL) extracted from synaptosomal plasma membrane vesicles was determined by employing a fluorescent probe technique. The two fluorescent probes 2-(9-anthroyl)stearic acid and 12-(9-anthroyl)stearic acid were utilized as probes for the surface and the hydrocarbon interior of the outer monolayer of the SPMVTL and SPMVPL, respectively. The Stern-Volmer equation of fluorescent quenching was modified to calculate the relative distribution. The analysis of preferential quenching of these probes by barbiturates indicates that pentobarbital, hexobarbital, amobarbital and phenobarbital are predominantly distributed on the surface area, while thiopental sodium has an accessibility to the hydrocarbon interior of the outer monolayer of the SPMVTL and SPMVPL. From these results, it is strongly suggested that the more effective penetration into the hydrocarbon interior of the outer monolayer of the membrane lipid bilayer could result in a higher general anesthetic activity.

• 대한화학회지
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• 제54권5호
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• pp.573-578
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• 2010

본 연구에서는 염화제1철을 2,4-디히드록시살로펜과 조합하여 2,4-디히드록시살로펜-염화철을 합성하였다. 이 복합체를 자외선-가시광선 분광법, IR 분광법으로 분석하였고, 천연의 송아지 흉선 DNA (ct-DNA)와 2,4-디히드록시살로펜-염화철의 상호작용을 자외선-가시광선 분광법, 형광분광법, 열변성 분석법, 점성측정법을 이용하여 조사하였다. 분광학적 적정실험으로 밝힌 2,4-디히드록시살로펜-염화철과 ct-DNA 사이의 결합상수는 $(1.6{\pm}0.2){\times}10^3\;M^{-1}$이었다. 형광분광분석을으로 브롬화 에티디움의 DNA 결합이 2,4-디히드록시살로펜-염화철에 의하여 저해되는 것을 관찰하였다. 이 저해효과는 2,4-디히드록시살로펜-염화철의 농도에 따라 선형의 Stern-Volmer 방정식을 따른다. 열변성 실험으로 2,4-디히드록시살로펜-염화철이 DNA의 녹는점을 약 $4.3^{\circ}C$ 증가시킨다는 것을 관찰하였다. 이 결과들은 2,4-디히드록시살로펜-염화철이 대부분 ct-DNA의 큰고랑과 상호작용한다는 모델을 잘 설명하여 준다.

• Bulletin of the Korean Chemical Society
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• 제29권8호
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• pp.1510-1518
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• 2008

Results of intrinsic and extrinsic fluorescence studies on choline oxidase revealed that the enzyme at high alkaline pH values has more accessible hydrophobic patches relative to acidic pH. Fluorescence quenching studies with acrylamide confirm these changes. The quenching constants were also determined at different pH(s) by using the Stern-Volmer equation. CD studies showed that at higher pH a transition from $\alpha$-helix to $\beta$- structure was appeared while at lower pH the content of $\alpha$-helix structure was increased. Furthermore, analysis of the spectral data using chemometric method gave evidence for existence of intermediate components at very high pH(s). Results of thermal denaturation evaluated that the enzyme has the most instability at higher pH(s). Altogether low and high pH values caused significant alteration on secondary and tertiary structures of choline oxidase via inducing of an intermediate.

• 대한기계학회논문집B
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• 제28권3호
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• pp.271-280
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• 2004

Assessment of image registration for Pressure Sensitive Paint (PSP) was performed. A 16 bit camera and LED lamp were used with Uni-FIB paint (ISSI). Because of model displacement and deformation at 'wind-on' condition, a large error of the intensity ratio was induced between 'wind-on' and' wind-off images. To correct the error, many kinds of image registrations were tested. At first, control points were marked on the model surface to find the coefficients of polynomial transform functions between the 'wind-off' 'wind-on' images. The 2nd-order polynomial function was sufficient for representing the model displacement and deformation. An automatic detection scheme was introduced to find the exact coordinates of the control points. The present automatic detection algorithm showed more accurate and user-friendly than the manual detection algorithm. Since the coordinates of transformed pixel were not integer, five interpolation methods were applied to get the exact pixel intensity after transforming the 'wind-on' image. Among these methods, the cubic convolution interpolation scheme gave the best result.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.1973-1977
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• 2009

In the present study, at first, 2,4-Dihydroxy Salophen (2,4-DHS), has been synthesized by combination of 1, 2-diaminobenzene and 2,4-dihydroxybenzaldehyde in a solvent system. This ligand containing meta-quinone functional groups were characterized using UV-Vis and IR spectroscopies. Subsequently, the interaction between native calf thymus deoxyribonucleic acid (ct-DNA) and 2,4-DHS, was investigated in 10 mM Tris/HCl buffer solution, pH 7.2, using UV-visible absorption and fluorescence spectroscopies, thermal denaturation technique and viscosity measurements. From spectrophotometric titration experiments, the binding constant of 2,4-DHS with ct-DNA was found to be (1.1 ${\pm}\;0.2)\;{\times}\;10^4\;M^{-1}.$ The fluorescence study represents the quenching effect of 2,4-DHS on bound ethidium bromide to DNA. The quenching process obeys linear Stern-Volmer equation in extended range of 2,4-DHS concentration. Thermal denaturation experiments represent the increasing of melting temperature of DNA (about 3.5 ${^{\circ}C}$) due to binding of 2,4-DHS. These results are consistent with a binding mode dominated by interactions with the groove of ct-DNA.

• The Korean Journal of Pain
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• 제6권2호
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• pp.237-246
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• 1993

세포막에서 마취제의 작용점을 규명하기 위하여, 마취제의 많은 부분을 차지하는 n-Alkanol을 이용하여, 소의 synaptosomal plasma membrane vesicles(SPMV)에서 n-Alkanol의 침투 정도를 형광 probe를 이용한 형광소광법을 통하여 검색하였다. n-Alkanols는 SPMV 외부 단층(outer monolayer)의 표면에 주로 분포하되 그 탄소수에 비례하여 소수성 부위에 분포되는 양이 증가되는 경향을 나타내었다(1-decanol은 제외). Methanol, Ethanol, 1-propanol, 1-butanol, 1-pentano, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol 및 1-decanil은 SPMV 외부 단층의 표면(친수성 부위)에 분포되는 것에 비하여 각각 949, 416.8, 214.8, 90.3, 53.7, 15.20, 6.80, 2.00, 1.03 및 2.40 배가 된다는 것을 확인하였다. 1-decanol은 $C_{10}$인데도 불구하고 $C_8$인 1-octanol에 비하여 적은 양이 소수성 부위에 침투 분포한다는 것이 확인되었다.