磷钨酸/乙炔黑修饰电极上的阿昔洛韦电化学行为及其测定

Electrocatlytic behavior and determination of aciclovir at phosphotungstic acid/acetylene black modified electrode

本文制备了磷钨酸/乙炔黑修饰电极(PTA/AB/GCE),用循环伏安法(CV)研究了阿昔洛韦(ACV)在该修饰电极上的循环伏安行为。结果表明在pH 6.0的磷酸盐缓冲液中,ACV在该修饰电极上出现一明显的氧化峰。在60～220mV.s-1扫速范围内,其氧化峰电流(Ipa)与扫速平方根(v1/2)呈线性关系,表明该电极过程是受扩散控制的不可逆过程。计算了电极过程的部分动力学参数:电极有效面积为0.06902cm2,转移电子数为2,扩散系数为2.063×10-6cm2.s-1。运用方波溶出伏安法测定不同浓度ACV的方波溶出伏安曲线,结果表明氧化峰电流(Ipa)与ACV浓度在7.8×10-7～1.0×10-4mol.L-1范围内呈良好线性关系(r=0.9924),检出限(S/N=3)为3.1×10-7mol.L-1,加标回收率为95.69%～107.2%。

A new biosensor was fabricated by the Phosphotungstic acid（ PTA ）and acetylene black （AB）to form a compound film on a glassy carbon electrode（GCE）. The electrochemical characterisistics of Aciclovir on PTA/AB/GCE were studied by using cyclic vohammetry. The ACV shows the sensitive oxidation peak that in the pH 6. 0 PBS buffer. The oxidation peak current was linear to v1/2 in the range of 60 - 220mV·s-1 , indicating the electrode process of ACV was controlled by diffusion. Square wave stripping voltammetry was use to determine the concentration of ACV. The peak current of ACV is linearly change with the concentration of ACV in the range of 7. 0×10^-7 to 1. 0×10-4mol·L-1 ,and the linear equation was Ipa（μA） = -0. 8172-17.93c（ 10^-4mol · L^-1 ）with the coefficient of 0. 9924. The detection limit is 3. 1×10^-7mol·L^-1（S/N=3）. The spiked recoveries of the samples were 95.69% - 107.2%. The PTA/AB/GCE shows the excellent selectivity,good repeatability and stability for the determination of ACV.