Department of Chemistry, Faculty of Science, University of Kurdistan, P.O. Box 416, Sanandaj, Iran.
Department of Chemistry, Faculty of Science, University of Kurdistan, P.O. Box 416, Sanandaj, Iran; Research Center for Nanotechnology, University of Kurdistan, P.O. Box 416, Sanandaj, Iran.
Biosens Bioelectron. 2011 May 15;26(9):3864-9. doi: 10.1016/j.bios.2011.02.048. Epub 2011 Mar 5.
For the first time a novel and simple electrochemical method was used for simultaneous detection of DNA bases (guanine, adenine, thymine and cytosine) without any pretreatment or separation process. Glassy carbon electrode modified with silicon carbide nanoparticles (SiCNP/GC), have been used for electrocatalytic oxidation of purine (guanine and adenine) and pyrimidine bases (thymine and cytosine) nucleotides. Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) techniques were used to examine the structure of the SiCNP/GC modified electrode. The modified electrode shows excellent electrocatalytic activity toward guanine, adenine, thymine and cytosine. Differential pulse voltammetry (DPV) was proposed for simultaneous determination of four DNA bases. The effects of different parameters such as the thickness of SiC layer, pulse amplitude, scan rate, supporting electrolyte composition and pH were optimized to obtain the best peak potential separation and higher sensitivity. Detection limit, sensitivity and linear concentration range of the modified electrode toward proposed analytes were calculated for, guanine, adenine, thymine and cytosine, respectively. As shown this sensor can be used for nanomolar or micromolar detection of different DNA bases simultaneously or individually. This sensor also exhibits good stability, reproducibility and long lifetime.
首次使用一种新颖且简单的电化学方法，无需任何预处理或分离过程，即可同时检测 DNA 碱基（鸟嘌呤、腺嘌呤、胸腺嘧啶和胞嘧啶）。玻璃碳电极经碳化硅纳米颗粒（SiCNP/GC）修饰后，可用于嘌呤（鸟嘌呤和腺嘌呤）和嘧啶碱基（胸腺嘧啶和胞嘧啶）核苷酸的电催化氧化。场发射扫描电子显微镜（FE-SEM）和透射电子显微镜（TEM）技术用于检查 SiCNP/GC 修饰电极的结构。修饰后的电极对鸟嘌呤、腺嘌呤、胸腺嘧啶和胞嘧啶具有优异的电催化活性。差分脉冲伏安法（DPV）用于同时测定四种 DNA 碱基。优化了不同参数（如 SiC 层的厚度、脉冲幅度、扫描速率、支持电解质组成和 pH），以获得最佳的峰电位分离和更高的灵敏度。分别计算了修饰电极对所提出的分析物（鸟嘌呤、腺嘌呤、胸腺嘧啶和胞嘧啶）的检测限、灵敏度和线性浓度范围。结果表明，该传感器可用于同时或单独检测纳摩尔或微摩尔水平的不同 DNA 碱基。该传感器还表现出良好的稳定性、重现性和长寿命。
