SQUAD

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1 - Physicochemical Study of the Interaction of some Water Soluble Porphyrins with Calf Thymus DNA
H. Aghaie M. Keshavarz K. Zare M. Aghaie A.K. Bordbar

In order to shed more light on the effect of peripheral groups of porphyrin core intophysicochemical properties and DNA binding behavior of porphyrins, we have chosen toinvestigate solution properties and calf thymus DNA binding behavior of meso-tetrakis (4-Nbenzyl-pyri أکثر

In order to shed more light on the effect of peripheral groups of porphyrin core intophysicochemical properties and DNA binding behavior of porphyrins, we have chosen toinvestigate solution properties and calf thymus DNA binding behavior of meso-tetrakis (4-Nbenzyl-pyridyl) porphyrin (TBZPyP) and its Mn (III), Co (III), Ni (II) and Cu (II) complexesderivatives have been studied in thermodynamic viewpoint using Uv/Vis spectroscopy. They havebeen chosen because of their good solubility in physiological solution as well as moderatelyhydrophobic property, so that we may consider them as promising compounds for clinicalapplications. The measurements were done in 1mM phosphate buffer, pH 7.0 and varioustemperatures. The optical absorption spectra of porphyrins were analyzed in order to obtainbinding constants and stoichiometries using SQUAD software. The results show that the bestfitting corresponds to a 1:1 complex model between base pair of DNA and porphyrins. Theestimation of binding constant at various temperatures enabled as to calculate all of thethermodynamic parameters of binding using vant Hoff equation. All of the studied porphyrinsshowed strong electrolyte effect and increasing of NaCl concentration induces self-aggregation ofporphyrins. We also made a comparison between the properties of above-mentioned porphyrinsand that of a less-hydrophobic water-soluble porphyrin [meso Tetrakis (4-N-Methyl-pyridyl)porphyrin (TMPyP). The results showed that the above-mentioned porphyrins exist as monomerat low ionic strength medium. While TBzPyP and CuTBzPyP formed ill-defined self-aggregatesat high strength medium. The hypochromicity among with small red shift has been observed inSoret band of porphyrins due to increasing of DNA. تفاصيل المقالة

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2 - Spectroscopic study on the interaction of three water-soluble porphyrins with calf thymus DNA
H. Aghaie M. Keshavarz K. Zare A.K. Bordbar F. Gharib

Porophyrins and their metal derivatives are strong DNA binders with association constant of to . Some of these compounds have been used for the radiations sensitization therapy of cancer and are targeted to interact with cellular DNA. Binding of porphyrins to DNA change أکثر

Porophyrins and their metal derivatives are strong DNA binders with association constant of to . Some of these compounds have been used for the radiations sensitization therapy of cancer and are targeted to interact with cellular DNA. Binding of porphyrins to DNA changes the expectral and other physic chemical characteristic of porphyrins, The mode of binding can be extracted from inspection of spectral changes of porphyrine. Hence, Uv-V is spectroscopy is one of the most usual techniques for such investigations. Moreover, measuring of these spectral changes at various molar ratio of DNA/porphyrin can led to calculate the binding constant and stoichiometry. In the present work, the interaction of three water soluble porphyrins, tetra (ptrimethyle) ammonium phenyl porphyrin iodide (TAPP) as a cationic porphyrin, tetra sodium meso-tetrakis (p-sulphonato phenyl) porphyrin (TSPP)as an anionic porphyrine and manganese tetrakis (p-sulphonato phenyl) porphyinato acetate (MnTSPP) as a metal porphyrine with calf thymus DNA have been comprehensively studied at 1mM phosphate buffer, pH 7.0 and various temperatures using Uv-Vis absorption spectroscopy. The results represent a bath chromic effect without any shift in maximum wavelengths, which can be related to the external binding mode without staching. The absorption data at all wavelength regions were analysis at various molar ratios of DNA/porphyrin for estimation of binding characteristic using SQUAD software. The result confirms the formation of 1:1complex between DNA and porphyrins. The MnTSSP has the highest affinity respect to TSPP and TAPP that can be represent the formation of axial bond between phosphate group of nucleotide and Mn in the central core of MnTSSP. However, the higher affinity of TAPP as a cationic porphyrin respect to TSPP as an anionic can be related to the role of electrostatic interactions. The results represent that the process is endothermic and essentially entropy driven. تفاصيل المقالة

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3 - Thermodynamic study of interaction between some transition metal ions and L-Alanine
H. Aghaie K. Zare F. Keshavarz Rezaei

Using UV-vis spectrophotometic method, the formation constants for interaction of Cd2+(aq) andCo2+(aq) ions with L-Alanine were experimentally studied at pH = 4.1 ± 0.01 (50mM of potassiumhydrogen phthalate buffer), ionic strength of 0.1M potassium nitrate and at أکثر

Using UV-vis spectrophotometic method, the formation constants for interaction of Cd2+(aq) andCo2+(aq) ions with L-Alanine were experimentally studied at pH = 4.1 ± 0.01 (50mM of potassiumhydrogen phthalate buffer), ionic strength of 0.1M potassium nitrate and at 5 differenttemperatures 15,20, 25,30 and 35°C. The optical absorption spectra of mixtures containingconsidered cations and L-Alanine were analyzed by using SQUAD software, in order to obtainthe formation constants and the stoichiometry of respect complexes. The best fitting of our resultsshowed that the 2:1 complex respect to each studied system (Cd2+(aq) + L-Alanine) and (Co2+(aq) +L-Alanine) is formed. Regarding the values of formation constants at different temperatures andusing Van't Hoff equation, enable us to calculate the respect thermodynamic functions offormation such as ΔH , ΔS , ΔG , … of studied complexes. تفاصيل المقالة

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4 - Complexation of Bis(acetylacetonate)oxovanadium(IV) with D–penicillamine at neutral medium
R. Hakimelahi M.A. Seyed Sadjadi H. Aghaie M. Aghaie

Neutral bidentate N-O type complexe of VO(II) has been synthesized through condensation of Dpenicillamine,(D-H2Pen), with Bis(acetylacetonate)- oxovanadium(IV),[VO(acac)2], at neutralmedium . The established schiff base(NO type) complex was characterized on the basis of أکثر

Neutral bidentate N-O type complexe of VO(II) has been synthesized through condensation of Dpenicillamine,(D-H2Pen), with Bis(acetylacetonate)- oxovanadium(IV),[VO(acac)2], at neutralmedium . The established schiff base(NO type) complex was characterized on the basis of IR andmass spectroscopy techniques.Besides,D-H2Pen binding behavior to[VO(acac)2] has been studiedin thermodynamic viewpoint using Uv/Vis spectroscopy.The measurments were done in 5mMphosphate buffer,pH 7.0 and various temperatures.The optical absorption spectra of[VO(acac)2]were analyzed in order to obtain binding constants and stoichiometries using SQUADsoftware.The results show that the best fitting corresponds to 1:2 metal to ligand, complexbetween [VO(acac)2] and D-H2Pen.The estimation of binding constant at various temperaturesenabled us to calculate all of the thermodynamic parameters of binding using Van,t Hoff equation. تفاصيل المقالة

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5 - Thermodynamic study of interaction between phthalocyanines with calf thymus DNA
M. Aghaie F. Naderi M. Monajjemi H. Aghaie N. Safari P.R. Jamaat

The experimental determination of formation constant for interaction of two water soluble phthalocyanines,Cobalt (II) 4,4',4",4'"-tetrasulpho phthalocyanine (CoTsPc ) and Manganese(II) 4,4',4",4"-tetrasulphophthalocyanine (MnTsPc ) , with calf thymus DNA have been studi أکثر

The experimental determination of formation constant for interaction of two water soluble phthalocyanines,Cobalt (II) 4,4',4",4'"-tetrasulpho phthalocyanine (CoTsPc ) and Manganese(II) 4,4',4",4"-tetrasulphophthalocyanine (MnTsPc ) , with calf thymus DNA have been studied by UV-Vis spectrophotometric methodat lrnM phosphate buffer , pH 7.4 and at 5 different temperatures 20,25,30,35 and 400CC . The changes of Uv-Vis absorption spectra during the titration of these phthalocyanines with calf thymus DNA revealed a largehypochromicity (up to 45%) of the phthalocyanines maximum bands, usually considered as proof ofphthalocyanine intercalation in to DNA. The calculated formation constants, Ks , according to theSQUAD software were in the range of 104-105 M-1.By using the Van't Hoff equation. The values of enthalpyand entropy changes associated to the (CoTsPc +DNA) and(MnTsPc+DNA) were determined .Then by using AG°=-RTLIIK, we calculated the values of AG° at consideredtemperatures. Our results showed strong electrolytic effects on phthalocyanines behavior and increasingNaCl concentration induced self-aggregation of the CoTsPc and MnTsPc. تفاصيل المقالة

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6 - Thermodynamic Study on the Interaction between Fe2+(aq) ion and LAlanine
K. Zare F. Keshavarz Rezaie F. Soleimani H. Aghaie

Using UV-VIS spectrophotometric method, the formation constant for interaction of Fe2+(aq) ion with L-Alaninewas experimentally studied at pH = 4.1 ± 0.01 (50mM of potassium hydrogen phthalate buffer), ionic strengthof 0.1M potassium nitrate and at 5 different te أکثر

Using UV-VIS spectrophotometric method, the formation constant for interaction of Fe2+(aq) ion with L-Alaninewas experimentally studied at pH = 4.1 ± 0.01 (50mM of potassium hydrogen phthalate buffer), ionic strengthof 0.1M potassium nitrate and at 5 different temperatures 15,20, 25,30 and 35 T. The optical absorption spectraof mixtures containing considered cation and L-Alanine were analyzed by using SQUAD software, in order toobtain the formation constant and the stoichiometry of respect complex. The best fitting of our results showedthe 1:2 complex respect to the studied system (Fe2+00 + L-Alanine) is formed. Regarding the value of formationconstants at different temperatures and using Van' t Hoff equation, it is possible to calculate the respectivethermodynamic functions of formation such as AG', An' , AS', ... of the studied complex. تفاصيل المقالة

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7 - Thermodynamic Studies on the Interaction of Phthalocyanine with Bovine serum albumin
K. Zare H. Aghaie M. Mirzaie M.R. Zardoost F. Khazali

Using UV-Vis spectrophotometric method the interaction of water soluble phthalocyanine, Cobalt(ΙΙ) 4,4′,4′′,4′′′- tetrasulfophthalocyanine(CoTSPc), with bovine serum albumin (BSA) to determine the formation constant and rela أکثر

Using UV-Vis spectrophotometric method the interaction of water soluble phthalocyanine, Cobalt(ΙΙ) 4,4′,4′′,4′′′- tetrasulfophthalocyanine(CoTSPc), with bovine serum albumin (BSA) to determine the formation constant and related thermodynamic functions. The measurements were considered in 1mM sodium phosphate buffer, pH 7.0 and at 5 different temperatures 20, 25, 30, 35 and 40ºC. The results showed that the best fitting corresponds to a 1:1 complex model between BSA and CoTSPc. The optical adsorption spectra of phthalocyanine was analyzed in order to obtain binding constants, K, using SQUAD software. By using the Van’t Hoff equation, values of enthalpy, ∆H˚,and entropy, ∆S˚,changes associated to the (BSA+ CoTSPc) were determined, and the values of ∆G˚ were calculated by using ∆G˚ = -RTlnK at 5 different temperatures. تفاصيل المقالة

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8 - Interaction of Phthalocyanine with Egg albumin and Bovine serum albumin
K. Zare H. Aghaie M. Mirzaie

The interaction of bovine serum albumin ( BSA) and egg albumin with water solublephthalocyanine, cobalt (ΙΙ) 4, 4′ , 4′′, 4′′′- tetrasulfophthalocyanine ( CoTSPc) , has been studiedby the UV- Vis method at pH 7.0 and five di أکثر

The interaction of bovine serum albumin ( BSA) and egg albumin with water solublephthalocyanine, cobalt (ΙΙ) 4, 4′ , 4′′, 4′′′- tetrasulfophthalocyanine ( CoTSPc) , has been studiedby the UV- Vis method at pH 7.0 and five different temperatures 20, 25, 30, 35 and 40°C. Theformation constants have been elucidated by using spectrophotometric titration and computerSQUAD program data refinement. The thermodynamic parameters ΔH°, ΔG°and ΔS° at 5 differenttemperatures were calculated. The results showed that the best fitting corresponds to a 1: 1complex model between BSA and egg albumin with CoTSPc. Formation constants decrease withincreasing temperature.The formation constants showed that bonding effect between egg albuminand CoTSPc is stronger than BSA. تفاصيل المقالة

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