Interaction of double stranded DNA with bulky and hydrophobic Salen type Schiff base complex: [N, N′ Bis [3- tert-butyl-5-[triphenyl-phosphonium – methyl] - salicylidene] 1,2 ethylene-diamine nickel(III) acetate (refer to Ni Salen complex) was extensively investigated using the spectroscopic techniques and gel electrophoresis. Absorption titration experiment showed the hypochromic effect and the significant red shift of the complex absorption. In competition experiments with ethidium bromide (EB), Ni Salen complex exhibited non-competitive binding at high concentrations. UV-vis absorption and fluorescence emission data agreed on a binding constant of (1.64 ± 0.01) μM⁻¹, thereby showing the strong interaction of the complex with DNA; also, a binding site size of 2.33 ± 0.01 base pairs per complex was achieved.

Thermal denaturation experiment showed that T_m of calf thymus-DNA was increased by approximately 10 °C at a molar ratio of the dye/base of 0.2. The CD spectra of DNA exhibited an increase in both positive and negative peaks without any shift in the position of bands upon addition of the complex. The amplitude of the LD spectra of DNA was decreased in the presence of the complex. Reduced linear dichroism (LD^red) revealed that the transition moment of complex was parallel to the DNA helix axis. Gel electrophoresis experiments confirmed that Ni Salen complex had no nuclease/DNA cleaving activity; also, DNA-DNA cross links were formed at high concentrations of complex, leading to the aggregation of DNA.

双链DNA与疏水性Salen型席夫碱配合物的相互作用：[N，N'Bis [3- 3-叔丁基-5- [三苯基-甲基]-水杨基] 1,2乙二胺镍（III）使用光谱技术和凝胶电泳对乙酸盐（称为Ni Salen络合物）进行了广泛研究。吸收滴定实验显示了复合物吸收的减色作用和显着的红移。在与溴化乙锭（EB）的竞争实验中，Ni Salen复合物在高浓度下表现出非竞争性结合。紫外可见吸收和荧光发射数据的结合常数为（1.64±0.01）μM ^-1，从而显示出复合物与DNA的强烈相互作用；同样，每个复合物的结合位点大小为2.33±0.01个碱基对。

热变性实验表明，当染料/碱的摩尔比为0.2时，小牛胸腺DNA的T _m增加约10°C。添加复合物后，DNA的CD谱图显示出正峰和负峰均增加，谱带位置无任何变化。在复合物的存在下，DNA的LD光谱的幅度减小。降低的线性二向色性（LD^红）表明，复合物的跃迁矩与DNA螺旋轴平行。凝胶电泳实验证实，Ni Salen复合物没有核酸酶/ DNA裂解活性。同样，DNA-DNA交联在高浓度的复合物中形成，导致DNA聚集。