基于Au@SiO_2纳米复合材料构建新型的DNA电化学传感器

合成了金包二氧化硅纳米复合材料(Au@SiO2),并将其修饰于玻碳电极表面,固定上DNA探针后构建了一种新型的DNA电化学传感器.采用循环伏安法、差分脉冲伏安法(DPV)对于复合材料的电化学性能进行了研究.以5.0 mmol/L的Fe(CN)6]3-/4-溶液为探针,分别对DNA的固定温度、固定时间、杂交温度以及杂交时间等试验条件进行了优化.结果表明:在优化条件下,利用DPV测定,目标DNA浓度的对数与峰电流在1.0×10-13¹.0×10-10mol/L范围内呈良好的线性关系,线性相关系数为0.995,检出限为1.0×10-15mol/L.该方法具有简单、快速、灵敏等优点.

A Novel DNA Electrochemical Sensor Based on Au@SiO2 Nanocomposite

Au@ SiO2 nanocomposite was prepared. A novel DNA electrochemical sensor was fabricated by coating Au@ SiO2 nanocomposite on glass carbon electrode and subsequently by immobilizing DNA probe on the modified electrode. The electrochemical behavior of the nanocomposite film was investigated by cyclic voltametry and different pulse voltametry(DPV). The experimental conditions including the immobilized temperature,immobilized time,hybridization temperature,and hybridization time were optimized using Fe(CN)6]3- /4-solution as probe. Under the optimization condition,the developed biosensor showed a good linear relationship between the current peaks and logarithm of the target DNA concentration in the range of 1. 0 × 10-131.0×10-10mol/L范围内呈良好的线性关系,线性相关系数为0.995,检出限为1.0×10-15mol/L.该方法具有简单、快速、灵敏等优点.Au@ SiO2 nanocomposite was prepared. A novel DNA electrochemical sensor was fabricated by coating Au@ SiO2 nanocomposite on glass carbon electrode and subsequently by immobilizing DNA probe on the modified electrode. The electrochemical behavior of the nanocomposite film was investigated by cyclic voltametry and different pulse voltametry(DPV). The experimental conditions including the immobilized temperature,immobilized time,hybridization temperature,and hybridization time were optimized using Fe(CN)6]3- /4-solution as probe. Under the optimization condition,the developed biosensor showed a good linear relationship between the current peaks and logarithm of the target DNA concentration in the range of 1. 0 × 10-13 1. 0 × 10-10 mol /L with a low detection limit of 1. 0 × 10-15 mol /L. The developed method has advantages of simplicity,rapidity and sensitivity.