• 대한약리학회지
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• 제31권1호
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• pp.135-140
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• 1995

Glycation이란 단당류의 카보릴기와 아미노산의 입실론 아미노기가 공유결합에 의하여 형성되는 반응으로 이는 단백질의 생리적 기능을 변화시키며 아울러 당뇨합병증을 유발한다. 본 연구에서는 warfarin과 dansylsarcosine의 단백질결합에 미치는 glycation의 영향을 평형투석법을 이용하여 연구하였으며 평형투석은 섭씨 37도의 진탕수조에서 3시간 동안 실시하였다. 약물의 농도가 알부민의 농도보다 높을 경우, $50{\pm}16%$가 glycation된 알부민은 $8.5{\pm}5.28%$ glycation 알부민을 함유한 정상알부민에 비해 약물과의 결합도가 낮았으나 warfarin의 농도가 알부민의 3배가 될 경우에만 유의성이 인정되었고(P<0.05) 6%의 차이를 보였다. 본 실험에 나타난 glycation에 의한 유리약물의 미미한 상승효과는 glycated albumin 농도가 낮은 생체내의 여건과, 실제로 사용되는 약물의 적정 치료농도가 낮고 또한 과도한 유리약물은 신장을 통하여 신속히 배설되는 이유로 당뇨환자의 신기능 손상이 없는한 glycation에 의한 유리약물의 상승은 약물중독의 위험요소로 작용되지 않으리라 생각된다.

• 공업화학
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• 제4권4호
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• pp.746-752
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• 1993

PCB와 HA 사이의 착화합 정도에 대한 양적인 측정을 위해 투석막을 이용한 평형실험이 여러 가지 변수에 대해 먼저 수행되었다. 활성탄에 대한 PCB의 흡착특성 파악을 위해서 HA가 용해된 물과 용해되지 않은 물을 이용하여 PCB에 대한 흡착평형 및 속도실험을 행하였다. 실험결과 HA에 대한 PCB의 착화합 정도는 PH, $Ca^{2+}$농도, 이온세기 및 HA의 농도에 큰 영향을 받는 것을 확인하였다. PCB의 활성탄에 대한 흡착능력은 HA가물에 존재할 때 크게 감소하였으며 흡착특성은 HA, PCB와 HA에 착화합된 PCB 등의 물질이 서로 경쟁적으로 활성탄에 흡착하게 되는 복잡한 특성을 보일 것으로 판단되었다.

• 분석과학
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• 제9권1호
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• pp.91-97
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• 1996

수계에서 화학물질의 독성에 대한 humic acid(HA)의 영향을 예측하기 위하여 HA와 화학물질간의 결합상수($K_B$)를 equilibrium dialysis를 이용하여 cartap, diazinon, fenobucarb, pentachlorophenol, P,P'-DDT를 대상으로 측정하였다. $K_B$의 실험치 및 옥탄올/물 분배계수를 이용한 예측치로부터 대상 화합물 중 P,P'-DDT를 제외하고는 HA에 의해 수계 독성에 영향을 줄만한 농도의 감소는 없을 것으로 추정되었다. 실제 자연환경에서는 $K_B{\geq}10^5$ 또는 $K_{ow}{\geq}10^6$ (log $K_{ow}{\geq}6$)인 화학물질에 대해서만 HA에 의한 독성감소 효과를 기대할 수 있는 것으로 생각 되었다.

• Archives of Pharmacal Research
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• 제27권9호
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• pp.978-983
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• 2004

The effects of glycyrrhizic acid (GLZ) on protein binding of diltiazem, verapamil, and nifedipine were investigated. Protein binding studies (human serum, human serum albumin (HSA) and (X1-acid glycoprotein (AAG)) were conducted using the equilibrium dialysis method with and without addition of GLZ. The binding parameters, such as the number of moles of bound drug per mole of protein, the number of binding sites per protein molecule, and the association con-stant, were estimated using the Scatchard plot. The serum binding of nifedipine, verapamil, and diltiazem was displaced with addition of GLZ, and the decreases of Ks for serum were observed. GLZ decreased the association constants of three drugs for HSA and AAG, while the binding capacity remained similar with addition of GLZ. Although the characteristics of interaction were not clear, GLZ seemed to mainly affect HSA binding of nifedipine rather than AAG binding, while GLZ seemed to affect both AAG- and HSA-bindings of verapamil and dilt-iazem resulting in a serum binding displacement.

• Bulletin of the Korean Chemical Society
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• 제23권8호
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• pp.1073-1077
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• 2002

Binding of dodecyl trimethylammonium bromide (DTAB) to human and bovine hemoglobin and globin samples has been investigated in 50 mM glycine buffer pH = 10, I = 0.0318 and 300 K by equilibrium dialysis and temperature scanning spectrophotometry techniques and method for calculation of average hydrophobicity. The binding data has been analyzed, in terms of binding capacity concept $({\theta})$, Hill coefficient (nH) and intrinsic Gibbs free energy of binding $({\Delta}Gbv).$ The results of binding data, melting point (Tm) and average hydrophobicity show that human hemoglobin has more structural stability than bovine hemoglobin sample. Moreover the results of binding data analysis represent the systems with two and one sets of binding sites for hemoglobin and globin, respectively. It seems that the destabilization of hemoglobin structure due to removal of heme group, is responsible of such behavior. The results indicating the removal of heme group from hemoglobin caused the depletion of first binding set as an electrostatic site upon interaction with DTAB and exposing the hydrophobic patches for protein.

• Bulletin of the Korean Chemical Society
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• 제25권6호
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• pp.791-795
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• 2004

The binding of cethyl trimethylammonium bromide, (CTAB) with human serum albumin (HSA) has been investigated at 5 mM phosphate buffer pH 7.0, 27 $^{\circ}C$ and various ionic strength using ion selective membrane electrodes. This method is faster and much more accurate than equilibrium dialysis technique, so provides sufficient and accurate data for binding data analysis. A novel and simple method was introduced for resolution and characterization of binding sets on basis of binding capacity concept. The values of Hill binding parameters were estimated for each set and used for calculation of intrinsic binding affinity. The results interpreted on basis of nature of forces which interfered in the interaction and represent the existence of three and two binding sets for binding of CTAB at $10^{-4}$ and $10^{-3}$ M of NaBr, respectively.

• Archives of Pharmacal Research
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• 제16권4호
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• pp.289-294
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• 1993

A binding protein of radio-labeled sanjoinine-A (fangufoline) in rat brain cytoplasm was investigated, using an equilibrium dialysis technique. The labeled agent was bound to the cytosol fraction with two distinctly different types of sets in calclum ion-dependent manner. The bound protein was identified as calmodulin by dgel filtration of the sanjoinine-A bound cytosol fraction on a Sephadex G-75 column. Calmodulin was bound to sanjoinine-A bound at two sets of binding sites in the calculated as two at high affinity sites $(Kd=1.1\;mu{M)}$ and four at low affinity sites $(Kd=3.1\;\mu{M)}$.

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.145-148
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• 2001

The interaction between tetradecyl trimethyl ammonium bromide (TTAB) with bovine ${\alpha}-lactalbumin$ has been investigated at pH = 9 and at $37^{\circ}C$ by isothermal titration calorimetry, equilibrium dialysis and UV-Vis spectrophotometry methods. The binding data from unusual Scatchard plot have been analyzed in terms of the Hill equation for three sets of binding sites. The calorimetric data show that TTAB interacts endothermically with ${\alpha}-lactalbumin$ and causes protein unfolding below 2 mM concentration of TTAB, which is confirmed by spectrophotometric data. The unfolding of the protein would be mainly due to occupation of the second set of binding sites.

• Bulletin of the Korean Chemical Society
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• 제17권4호
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• pp.358-362
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• 1996

The ionic strength dependent binding mode of 9-aminoacridine (9AA), a well-known DNA intercalator, to DNA is studied by flow linear dichroism, circular dichroism, fluorescence techniques and equilibrium dialysis. The DNA-bound 9AA exhibits spectral properties corresponding to the intercalative binding mode disregarding the salt concentrations; the angle between the long-axis transition moment of the 9AA molecule and DNA helix axis is calculated to be about 65°, indicating a significant deviation from the classical intercalation. At low salt concentrations, however, upwards bending curve in Stern-Volmer plot is observed (where 9AA is a fluorophore and DNA a quencher), indicating the coexistence of both static and dynamic quenching mechanisms or the existence of an additional binding site.

• 대한방사선기술학회지:방사선기술과학
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• 제11권1호
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• pp.25-31
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• 1988

Studies on the clinical significance with Amerlex $FT_{4}$ RIA kit observing the determination of $FT_{4}$ were investigated using a tracer as $^{125}I-T_{4}$ derivative which is not almostly bound to thyroxine binding globulin, etc. The results are followed; 1. $FT_{4}$ value($1,55{\pm}0.38ng/100ml$) of normal group was not accorded that of hyperthyroidism with Amerlex $FT_{4}$ RIA kit, and was higher than that of hypothyroidism. 2. $FT_{4}$ value was lower level in chronic-kidney disfunction syndrome whereas, it was normal in a cancer patient, a woman in pregnancy and a patient in TBG disfunction. 3. The value of this method is a good corelationship at that of equilibrium dialysis method. (r=0.931) 4. $FT_{4}$ value by this kit was linear relationship to those of the other kit (Gamma Coat and Liquisol), and the normal value of each methods was also similar. As mentioned above, this method is more simple and rapid, compared to the other method. Therefore, it was thought that this method is a very useful clinically.