Department of Chemistry, School of Sciences, Alzahra University. P.O. Box 1993891176, Tehran, Iran.
Int J Biol Macromol. 2013 Feb;53:101-6. doi: 10.1016/j.ijbiomac.2012.11.021. Epub 2012 Nov 23.
The interactions of sulfadiazine (SD), an antimicrobial drug, with double-stranded calf thymus DNA on the multi-walled carbon nanotubes modified glassy carbon electrode (MWCNT-GCE) have been studied by cyclic voltammetry and UV-vis spectroscopy. In the presence of DNA, the oxidation peak current of SD decreases and the peak potential shifts to a positive potential which indicates the interaction of SD with DNA. The binding of SD with DNA shows both electrostatic and intercalative modes. The binding of SD with DNA, when analyzed in terms of the cooperative Hill model, yields the binding constant, K(a)=2.87 × 10(3)M(-1) and a Hill coefficient m=1.9 in Britton-Robinson (B-R) buffer solution, pH=6.5. This electrochemical method was further applied to the determination of DNA. Under the selected conditions, two linear calibration curves for DNA detection were obtained in the concentration ranges from 0.03 to 0.13 μgmL(-1) and 0.60-3.50 μgmL(-1) with detection limit 0.03 μgmL(-1). The method was also applied to the determination of DNA in human blood plasma sample.
磺胺嘧啶（SD）是一种抗菌药物，其与双链小牛胸腺 DNA 在多壁碳纳米管修饰的玻碳电极（MWCNT-GCE）上的相互作用通过循环伏安法和紫外可见光谱进行了研究。在 DNA 存在的情况下，SD 的氧化峰电流减小，峰电位向正电位移动，这表明 SD 与 DNA 相互作用。SD 与 DNA 的结合显示出静电和嵌入两种模式。当根据协同 Hill 模型分析 SD 与 DNA 的结合时，在 Britton-Robinson（B-R）缓冲溶液中，pH=6.5 时，得到结合常数 K(a)=2.87×10(3)M(-1)和 Hill 系数 m=1.9。该电化学方法进一步用于 DNA 的测定。在选定的条件下，在 0.03 至 0.13 μgmL(-1)和 0.60-3.50 μgmL(-1)的浓度范围内，得到了两个用于检测 DNA 的线性校准曲线，检测限为 0.03 μgmL(-1)。该方法还用于人血浆样品中 DNA 的测定。
