Anjomshoa Marzieh, Fatemi Seyed Jamilaldin, Torkzadeh-Mahani Masoud, Hadadzadeh Hassan
Department of Chemistry, Shahid Bahonar University of Kerman, Kerman 76169-133, Iran.
Department of Biotechnology, Institute of Science, High Technology & Environmental Science, Graduate University of Advance Technology, Kerman, Iran.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 Jun 5;127:511-20. doi: 10.1016/j.saa.2014.02.048. Epub 2014 Mar 6.
Binding studies of a mononuclear zinc(II) complex, [Zn(dppt)2Cl2] (dppt is 5,6-diphenyl-3-(2-pyridyl)-1,2,4-triazine), with DNA and bovine serum albumin (BSA) have been investigated under physiological conditions. The binding properties of the complex with fish sperm DNA (FS-DNA) have been investigated by UV-Vis absorption, thermal denaturation, competitive DNA-binding studies with ethidium bromide (EB) by fluorescence, and gel electrophoresis techniques. The competitive study with (EB) shows that the complex can displace EB from the DNA-EB system and compete for the DNA-binding sites with EB, which is usually characteristic of the intercalative interaction of compounds with DNA. The value of the fluorescence quenching constant (Ksv) was obtained as 3.1×10(4)M(-1), indicating that this complex shows a high quenching efficiency and a significant degree of binding to DNA. Moreover, the intercalative binding mode has also been verified by the results of UV-Vis absorption, thermal denaturation and gel electrophoresis. The value of Kb at room temperature was calculated to be 1.97×10(5)M(-1), indicating that the complex possesses strong tendency to bind with DNA. This value is very greater than to the values obtained for other zinc(II) complexes. The interaction of the complex with BSA has been studied by UV-Vis absorption, fluorescence and circular dichroism (CD) spectroscopic techniques. The results indicate that the complex has a quite strong ability to quench the fluorescence of BSA and the binding reaction is mainly a static quenching process. The quenching constants (KSV), the binding constants (Kb), the number of binding sites at different temperatures, the binding distance between BSA and the complex (r), and the thermodynamic parameters (ΔH(o), ΔS(o) and ΔG(o)) between BSA and the complex were calculated. The complex exhibits good binding propensity to BSA showing relatively high binding constant values. The positive ΔH(o) and ΔS(o) values indicate that the hydrophobic interaction is main force in the binding of the complex to BSA. Moreover, to evaluate the anticancer properties, the cytotoxicity of the complex has been tested against the human breast adenocarcinoma (MCF-7) cell lines using the MTT assay. The results indicate that the parent complex displays cytotoxicity against human breast cancer cell lines (MCF-7) with an IC50 value of 10.44μM. It is remarkable that the complex can introduce as a potential anticancer drug.
在生理条件下，对单核锌（II）配合物[Zn(dppt)₂Cl₂]（dppt为5,6 - 二苯基 - 3 -（2 - 吡啶基）- 1,2,4 - 三嗪）与DNA和牛血清白蛋白（BSA）的结合研究进行了考察。通过紫外 - 可见吸收光谱、热变性、与溴化乙锭（EB）的荧光竞争DNA结合研究以及凝胶电泳技术，研究了该配合物与鱼精DNA（FS - DNA）的结合特性。与EB的竞争研究表明，该配合物能从DNA - EB体系中取代EB，并与EB竞争DNA结合位点，这通常是化合物与DNA发生嵌入相互作用的特征。荧光猝灭常数（Ksv）的值为3.1×10⁴ M⁻¹，表明该配合物具有较高的猝灭效率和与DNA显著的结合程度。此外，紫外 - 可见吸收光谱、热变性和凝胶电泳的结果也证实了嵌入结合模式。室温下计算得到的Kb值为1.97×10⁵ M⁻¹，表明该配合物具有与DNA结合的强烈倾向。这个值远大于其他锌（II）配合物得到的值。通过紫外 - 可见吸收光谱、荧光光谱和圆二色性（CD）光谱技术研究了该配合物与BSA的相互作用。结果表明，该配合物具有很强的猝灭BSA荧光的能力，结合反应主要是一个静态猝灭过程。计算了猝灭常数（KSV）、结合常数（Kb）、不同温度下的结合位点数、BSA与配合物之间的结合距离（r）以及BSA与配合物之间的热力学参数（ΔH⁰、ΔS⁰和ΔG⁰）。该配合物对BSA表现出良好的结合倾向，显示出相对较高的结合常数。正的ΔH⁰和ΔS⁰值表明疏水相互作用是该配合物与BSA结合的主要作用力。此外，为了评估其抗癌性能，使用MTT法测试了该配合物对人乳腺腺癌（MCF - 7）细胞系的细胞毒性。结果表明，母体配合物对人乳腺癌细胞系（MCF - 7）具有细胞毒性，IC50值为10.44μM。值得注意的是，该配合物可作为一种潜在的抗癌药物。
